This is just some general info that i have gathered from various sources I like to be able to refer back to it when im having any setup issues. Long read. Enjoy.
Jim

Shock Absorbers

How do you know where to start? Trial and error, but a camber gauge will help before you get to the track.
Cornering traction is more important to me, so I use the camber gauge to measure camber as I force the
chassis to roll side to side and adjust the camber links (both front and rear) to maintain desired camber.
Then fine tune at the track. I would start at the top middle of the hub and middle of the tower hole for
combo of cornering and straight line traction (seems a few racer setup sheets are setup this way).
Adjust from there for your track.

--------------------------------------------------------------------------------

Shock absorbers and springs are universally the most misunderstood, yet critical part of any car
suspension - particularly an off-road R/C buggy. When your car can be jumping up to three feet into the
air and flying anything up to 10 feet before landing, it's important that your shock absorbers and springs
can control the car on landing. The difficulty is that those same shocks and springs have to help the car
get around corners, and manage over innumerable smaller bumps, ruts, holes and lumps of rock and dirt.
Sounds like quite a feat! Perhaps more than any other part of the car setup, choosing the right combination
of shock absorber and spring setup is a compromise. You need to weigh very carefully the need to get the
car through the corners - for which low ride height, stiff springs and 'hard' dampers can help - with the need
to help the car soak up bumps and jumps (high ride height, softer springs and lighter damping!). Let's start
by taking a look at the shock absorbers and how they work - what each adjustment does.



It is the shock absorbers job to control the cars suspension. While the springs keep the car off the ground, the shocks must control, or slow down, the springs action. Just how much to slow down that action is the great dilemma in setting up shock absorbers.

A shock absorber typically contains a number of parts: the shock body keeps it all together and contains the shock oil; the shock shaft protrudes from the shock body and connects the piston at one end, and the suspension arm at the other. Shock seals keep all the oil on the inside (where it belongs), while the volume compensator makes allowance for the oil that is displaced when the shock shaft and piston enter the shock body. The 'damping' effect of a shock absorber comes from the resistance of the piston to moving through the
oil-filled shock body.

The variable parts of a shock absorber are the length of the overall unit, length of shock shaft, travel limiters on shock shaft (both inside and outside the shock body), the piston attached to the shock shaft, and finally the viscosity (thickness) of the silicone shock oil used to fill the shock body. Let's take a look at each of these adjustments and the likely effect on your car.

Shock Oil

Shock Oil is the simplest, most universally used adjustment to the shock absorber. Using thicker shock
oil will help to 'slow down' the suspension motion of the car while lighter oil will do the opposite -
letting the suspension react more quickly to the demands of the track. Thicker oil is most often used when track conditions are smooth, and hard packed and traction is high. In these conditions suspension movement detracts from the handling of the car.

Thicker oil is also useful for controlling the car when landing off big jumps. When the going gets rough - if there are numerous ruts and holes or a lot of small jumps, or if the track is particularly slippery - lighter shock
oil should be used. This will let the car react more quickly to the track - helping to keep the tires in contact with the track.

Shock oil viscosity (or thickness) is measured in weights. The higher the number, the thicker the oil. While most companies' shock oil is reasonably close to each other's, there are some slight variations. Why?
I have no idea! The solution is to try and always use oil of the same brand. It doesn't particularly matter which brand of oil you use, but you should try to always use the same brand.

Shock Pistons

Shock Pistons are a bit of a black art as far as many racers are concerned. Variables in shock pistons include
the size, and number of holes in the piston. Pistons with larger holes allow the shock oil to travel through more quickly, while smaller holes will slow the travel of oil through the piston. The difficulty is in knowing how to
using this adjustment. In most conditions, your car's standard piston configuration will be fine. When the track is particularly rough, with lots of small to medium bumps and holes, pistons with larger, or more, holes
will be helpful. When the track is smooth, or if it has big jumps or drop-offs, smaller holed pistons could be the way to go.

What is important to remember is that pistons and shock oil have a very close relationship. Sometimes if you change one, you need to change to other. An example of this would be that when fitting larger holed
pistons to your car your should probably use slightly thicker shock oil. Most manufacturers offer a range of pistons for their shock absorbers and there are a number of after market alternatives.

Alternatively, some drivers have taken to drilling different sized holes in their shock pistons.
This is particularly common amongst team drivers to make very small adjustments. Such fine adjustment is not really necessary for the majority of us and should be left as a last resort. Similarly, the use of 'dual stage' pistons which have a different action on the up stroke when compared to the down stroke is probably not advisable for drivers early in their R/C career.


Losi Pistons
smallest hole to biggest
60 white
57 black
56 red
55 orange
54 blue
_______

Springs

Springs are a very useful adjustment for the suspension of your car. Springs vary in length, and 'stiffness'.
A 'stiffer' spring is harder to compress between your fingers than a 'softer' spring. Stiffer springs will tend
to hold the car up off the ground more, while softer springs can allow the car to ride lower, and to 'roll' from side to side more.

Springs, Jumps and Bumps

Springs are often changed to reflect the size and shape of bumps and jumps on a track. If your track is
relatively smooth with lots of big jumps, you should try a slightly stiffer spring to help the car land off jumps
without bottoming out. On the other hand, if the track has lots of bumps and ruts, but no real large jumps you can try a softer spring - to let the suspension soak up the little bumps without effecting the chassis balance too much.

Springs and Handling

Oddly enough, the springs you choose can have a large impact on handling of your car.
Changing to stiffer springs will generally result in lower traction at that end of the car - e.g. putting a stiffer spring on the front of your car will often give you slightly less steering while adding a softer spring to the rear can give more rear grip - to a point. Amazingly, in some conditions, the opposite can be true - stiffer springs can add traction.

If you are racing on a high traction track, sometimes adding a stiffer spring can give you more traction
by helping the suspension to keep more pressure on the tires. Remember this one if you're on a high traction track. Most importantly remember that when you're choosing springs - there's a compromise between handling and ability to cope with bumps and jumps. You've got to experiment a little to find the right combination for each track!


Spring Clips and Spacers

Many people adjust the compression or pre-load of their springs by either adding spring clips to the shock
body, or moving the 'spring collar' up or down the shock body. This adjustment is only for adjusting the ride height of your car. Adjusting the spring compression does not stiffen or soften your springs. For more
discussion of ride height and its effect on handling see (Suspension Geometry).

It's good to have a range of springs to choose from. Most manufacturers color code their springs to help
you identify stiffer and softer springs.

FRONT BUGGY SPRINGS
Losi Part #
A-5128 2" Spring 2.5 Rate (Red)
A-5129 2" Spring 2.9 Rate (Orange)
A-5130 2" Spring 3.2 Rate (Silver)
A-5132 2" Spring 3.5 Rate (Green)
A-5134 2" Spring 3.8 Rate (Blue)
A-5135 2" Spring 4.1 Rate (Black)

REAR BUGGY & TRUCK (front and rear) SPRINGS
Losi Part #
A-5144 2.75" Spring 1.4 Rate (Gold)
A-5146 2.75" Spring 1.6 Rate (Gray)
A-5147 2.75" Spring 1.8 Rate (White)
A-5148 2.75" Spring 2.0 Rate (Yellow)
A-5150 2.5" Spring 2.3 Rate (Pink)
A-5152 2.5" Spring 2.6 Rate (Red)
A-5154 2.5" Spring 2.9 Rate (Orange)
A-5156 2.5" Spring 3.4 Rate (Silver)
A-5158 2.5" Spring 3.7 Rate (Green)
A-5160 2.5" Spring 4.1 Rate (Blue)

ae

__BUGGY AND TRUCK REAR
6481 BLACK 1.74
6480 GREEN 1.90
6478 SILVER 2.10
6482 GRAY 2.33
7434 BLUE 2.55
7435 GOLD 2.75
7436 RED 2.95

TRUCK FRONT SPRINGS
7426 BLACK 2.76
7427 GREEN 2.99
7428 SILVER 3.22
7429 BLUE 3.45
7425 GOLD 3.70
7430 RED 3.90

BUGGY FRONT & 10L CENTER
6493 BROWN 2.80
8232 BLACK 3.20
6494 GREEN 3.50
6496 SILVER 3.85
6497 BLUE 4.20
__________________________________________________ __________________________________________________-_______________________________

Travel Limiters are small spacers placed over the shock shafts to limit the travel of the shock absorber.
Limiters placed outside the shock body limit the 'up travel' of the shock absorber, while placing spacers
inside the shock body limit the down travel (and hence overall length) of the shock absorber. This is not
an adjustment commonly used - once set it's usually forgotten.

Adding travel limiters to the inside of the shock absorber can be particularly useful on a very smooth track,
while a track with big jumps will probably see some drivers adding limiters to the outside of the shock
absorber - to prevent 'bottoming out' of the chassis on landing. Again, this is an adjustment not commonly
used in the early stages of your racing. Set the shock limiters according to the manufacturers' suggestions
and you'll be fairly close.

Shock Shafts

Shock shafts can sometimes be changed to longer, or shorter units if more, or less overall travel is required.
This type of adjustment is used only very rarely or in extreme circumstances on a very small range of cars.
Again, the best advice is to consult your local 'pro' driver and see whether they are using longer, or shorter
shock shafts.


Shock Mount Positions

R/C cars offer differing standards of tuning options from manufacturer to manufacturer. Almost without
exception they all offer alternate mounting options for shock absorbers. Mostly, the options relate to the
distance along the suspension arm that the shock mounts, or the angle of the shock (by altering the top
shock mount position). These two options provide various responses in terms of the handling of your car.
Let's take a look:

Moving the bottom of the shock along the suspension arm basically affects the 'stiffness' and 'drop' of the
suspension. Moving the shock mount further out results in a suspension that appears both 'stiffer' (sprung)
and 'harder' (damped). Conversely moving the shock inward gives a softer feel. The reason for this is simple.
The easiest way to explain this is to think back to the playground seesaw of your childhood. Remember that
even if the people on either end don't weigh the same - simply by moving the heavier person closer to the
center - the seesaw can be made to balance. It's simply a question of leverage. As the shock moves out
along the arm, it can bring greater leverage to bear on the suspension arm. Moving the bottom of the
shock along the arm also affects the suspension drop - further out equals less drop, further in equals
more drop. Suspension drop is covered in depth in another Section of this book.

Moving the top of the shock absorber has a more subtle effect on the car's suspension. What is changing
here is the angle of action of the shock absorber. Changing the angle makes the shock absorber more,
or less, progressive. A progressive suspension setup describes the situation where the suspension
becomes stiffer as the shock/spring/suspension is compressed. Leaning the shock absorber
over further results in a more progressive suspension. This is useful in landing off big jumps
(helps stop the car from bottoming out), handling on smooth tracks, handling in high-speed corners.
Standing the shocks straighter helps in rough conditions, or tracks with lots of quick changes of direction.
Adding interest to this setup option is the fact that leaning the shocks in gives some degree of anti-roll
effect while standing them straight up encourages, or allows, more chassis roll. The shock angle you
choose can thus be closely related to the use of an anti-roll bar.

Less inclined shock position
Front or rear: Makes the initial shock damping stiffer
Decreases lateral traction
Makes the vehicle more responsive
Makes the vehicle less forgiving and less stable

More inclined shock position
Front or rear: Softens initial shock damping
Makes shocks more progressive
Makes the vehicle more stable
Makes the vehicle more forgiving
Increases lateral traction
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Suspension Geometry

Trying to explain suspension geometry is not an easy thing. We'll try to give you an overall picture of what 'geometry' is and does - and give you some general hints on what changes affect the handling
of your car. More than any other section of this book, the motto for this chapter must be: change your
car, practice, change your car, practice, change your car, practice..... You sometimes just have to make
a change to the car and try it - and do your best to pick out the difference. Suspension geometry refers to a
lot of things. Basically, it is the various angles and mounting points of wheels, axles, suspension arms and
uprights. Shock absorber mounting positions can also be considered to be suspension geometry
but we've already covered them in another Section so we won't do it again. Words most commonly
heard when talking about suspension geometry are camber, caster, ride height and toe-in. If you
don't understand what's meant by these terms - look them up in the Glossary before you go any further.

Camber

Camber is probably the easiest component of suspension geometry to adjust - if your car is fitted
with turnbuckles or some kind of threaded rod for an upper suspension link. Here are some general
rules of thumb.

Front Camber

On the front of your car or truck - adding negative camber will, in general, slightly increase steering

up to a certain point - and then decrease it after that. That point is around 3-4 degrees.
I would suggest that you start with about 2 degrees of negative camber (whatever the car)
and NEVER adjust it more than 1 degree either way. Running more negative camber will simply
take away too much steering and add unpredictability to your car's handling, while running positive
camber of any kind is generally not a great idea. Positive camber can induce unstable handling -
and a particular loss of traction for the outside tire in any corner (and the outside tire is the one that
does about 80% of the work).

Rear Camber

On the rear things get a little more complicated. We need to consider both driving traction and cornering
traction. Driving traction is what gets us going in a straight line - the more you have, the faster you can
accelerate. Cornering traction is what helps the car to track around corners - without the back of the car
spinning out. In general, the most driving traction comes with the tires at 0 degrees camber - neither
positive or negative. This is because the tire is flat to the track with the most possible amount of rubber
touching for more grip.

Unfortunately, cornering traction can be enhanced by adding a little negative camber - just like the front
of the car. Interestingly enough, most cars will run fairly consistently with around 2 degrees of negative
camber on the rear. Again - as per the front, I would suggest that you adjust this by only 1 degree either
way. Again, NEVER run positive camber – it will lead to unpredictable driving traction - and probably a
lot of spin outs in corners.

Camber Link Mounting Positions

The idea is that unequal length, non-parallel, double wishbone suspensions will be the most resistant to camber changes when considering body roll in a corner. Think about what you want from the suspension, straight line traction, turning traction or a combo of both. That will define where you put the camber link.

Remember, increasing traction loss or instability in turns is largely due to undesired camber changes and toe changes.

2 things to consider. The height and the angle/length of the camber link, since you can adjust the inboard
camber point on the tower too. First, the higher you put the link on your tower and hub, the more force the wheel can counteract and the less deflection of the wheel will occur. This means there will be less positive camber change as the side force on the wheel increases in a turn, maintaining contact patch and traction.

The angle and length of the link will help maintain the desired camber through the suspension's stroke.
If you want straight traction, camber link needs to be flat and longer, so when the suspension compresses during acceleration, there is minimal camber change, maintaining contact patch. If you want cornering traction, the camber link needs to be angled (lower at tower than hub) and shorter.

Roll Center / Camber links

Long Link-A long link gives a lot of body roll in turns.
It feels as is the body is willing to keep on rolling, until in the end, the springs prevent it from rolling any further.

The car has more grip in corners, especially the middle part.
Short Link-A short link makes that the body doesn't roll as far, its tendency to roll drops off as it rolls.
This can stabilize a car in bumps and curved sections.
It feels as is the car generates a little less grip.
Parallel Link (Parallel to lower arm) A parallel link gives a little more roll than an angled one.
It feels very smooth, and consistent as the body rolls in turns.
Angled Link-(Distance between arm and link is smaller on the inside)-An angled link makes it feel as if the car has a tendency to center itself (level, no roll), other than through the springs or anti-roll bar.
It gives a little more initial grip, steering into corners. It makes it very easy to 'throw' the car.
The body rolls a little less than with parallel links.
On bumpy tracks, it could be possible to use softer settings for damping and spring rate than with parallel links, without destabilising the car.
Beware that you should always keep an eye on the balance of your car; large differences in roll center front vs. rear will make the car feel less consistent and less confidence-inspiring.

Longer Front-The front rolls and dives more in turns.
Lots of steering in mid-corner.
Could make the car hook.
Shorter Front-The front feels very stable.
A little more turn-in, but less steering in mid-corner.
Longer Rear-More rear traction in turns, and coming out of them.
Rear end slide is very progressive, not unpredictable at all.
Make sure that there's enough rear camber though, or you could lose rear traction in turns.
Shorter Rear-The rear feels very stable. It breaks out later and more suddenly, but if it does, the slide is more controllable.
It makes the front dive a little more, which results in more steering, especially when braking.
More Angled Front-Turn-in is very agressive.
The front feels as if it wants to roll less than the rear.
More Angled Rear-The rear end is rock-solid while turning in. It feels very confident.
-----------------------------------------------------------------------------------------------------
Caster and Anti-Squat

Caster and Anti-Squat are basically the same thing - except that caster refers to the angle of the suspension 'upright' (and is generally used in reference to front suspension) while anti-squat
refers to the angle from horizontal of the whole suspension arm mounting pin (and is generally used in reference to rear suspension). Let's take a look.

Caster adjustment on the front of most buggies is by using different front uprights. In most cases, 2wd
cars run between 20 and 30 degrees of caster, while 4wd cars run a bit less - typically 10 to 15 degrees.
This is another instance where your manufacturer has done a lot of work to find the best answer - in general you should trust them. However, there are some generalizations that can be made.
Adding caster (leaning the uprights further back) will generally give less initial turn-in, but more
on-power steering and better straight line stability, while decreasing caster will generally add some turn-in, but at the expense of on-power steering and straight line stability.

The other possibility is that your car may be fitted with a 'variable caster' or 'active caster' setup.
This means that as the suspension compresses, or extends, the caster automatically changes.
While common in on-road cars, variable (or 'active') caster is less common on the dirt.
Anti-squat
Anti-squat adjustments are available on the rear of most modern buggies and trucks. Anti-squat is
typically adjusted by either replacing the rear suspension arm mounts, or placing washers or wedges under one end or the other of the mount before tightening the mounting screws. This results in a change in the angling the suspension arm - lifting the front edge of the arm higher than the rear edge. Anti-squat
does exactly what you might guess by its name - it prevents the rear end of the car from squatting under power as the car accelerates and weight transfers rearwards. Anti-squat does also have some other effects (as with any adjustment – there is always a trade off). Let's take a look at the effect of altering
anti-squat on both acceleration and cornering.

Adding Anti-Squat
If you add anti-squat, your car will (in general) get more 'driving traction' and hence accelerate faster. When you come out of corners, you will be able to use more throttle and your car will be more stable.
But (and it's a BIG but), when you back off to turn into a corner, your car will have less rear grip.
This might result in your car spinning out when you back off the throttle. Adding anti-squat also affects
the way your car drives through bumps on the track. If the track is bumpy right where you want to
accelerate, anti-squat is not a good thing - it will make the rear of your car very 'bouncy'. On the other hand, if the rough stuff is in a place where you are cruising on constant throttle, or even decelerating, then anti-squat will actually help your car to 'cruise' through the bumps more smoothly.

Decreasing Anti-Squat
When you decrease anti-squat you lose rear 'driving' traction. Your car will be a little more prone to

power slides and fishtails. However, you will have more traction on a trailing throttle - resulting in your
car being more stable into corners. It will also accelerate better through bumpy parts of the track.
--------------------------------------------------------------------------------------------------------
Toe

The adjustment of toe is one of the most useful fine-tuning aids in making your car handle just how you like it.
On the front of your car, lengthening or shortening the steering rods adjusts toe; while on the rear it is
usually adjusted by changing the suspension arm mounts, or using different hub carriers or suspension uprights.

Essentially, toe adjustment works like this: Adding toe-in (front of wheels point inward) adds straight-line
stability, while adding toe-out (front of wheels point outward) tends to make the car wander a little.
Like all suspension geometry adjustments - this is only true up to a certain point - beyond which the
results are generally unpredictable. Let's look at that in a little more detail.

Front adjustment
Changing toe on the front wheels is probably the best way to get that last little fine tuning adjustment right.
Adding a little toe-in will reduce turn in slightly, and produce a car that tracks well in a straight line.
On the other hand, reducing toe-in, or adding a little (very little) toe-out can provide a slight increase in
steering. As with all suspension adjustments - go a little at a time. Front toe adjustment should never
exceed 3 degrees negative, or 1-degree positive.

Rear adjustment
Due to the nature of rear toe-in (adjusted by replacing suspension mounts or hub carriers/uprights),
adjustment of rear toe-in is quite uncommon. Just as with the front adjustment, more toe-in will add traction and stability, while less will promote sliding and instability. Rear toe-in should probably never exceed 4 degrees negative or be less than 2 degrees negative. Most modern cars are supplied at 3 degrees negative and will never need to be changed.

The other interesting part of rear toe adjustment is that some cars use different suspension arm
mounts to achieve the adjustment, while others use different suspension uprights to make the change.
The first case (suspension arm mounts) is called 'inboard toe-in' because adjustment is made at the inboard end of the suspension arm and affects the whole arm. Altering the upright is called 'outboard toe-in' because (you guessed it) it's making an adjustment at the outboard end of the arm. Inboard toe-in can produce slightly different handling characteristics to outboard toe-in in rough track conditions.

Ride Height

Ride height describes the distance between the track surface and the underside of your car's chassis. Sounds simple. The simple truth is, ride height adjustment can sometimes be easy to get wrong -
and can have a devastating effect on your car. Fortunately, there are some relatively simple rules that you can follow to help make sure you get the ride height correct - most of the time.

First, let's accept this basic fact: Ride height is controlled by the amount of pre-load applied to your
springs through the use of spring spacers, or the movement of an adjustable spring collar. Adding
spring spacers does not stiffen the spring - it just lifts the car higher off the ground. You can also adjust
ride height by using travel limiters inside the shock absorber or by selecting different shock mounting
positions on some cars. Basically though - spring pre-load is it.

Simple Rule 1
Always run the car with the chassis level. That is - the ride height at the front must equal the ride height
at the rear. While there may be some very odd circumstances where you'll want to run the front higher
than the rear (or some even more odd circumstances where you'll want to run the front lower than the rear), it is true for most conditions that the car will be most consistent if the front and rear ride heights are equal.

Simple Rule 2
The rougher the track, the higher the ride height must be. As the race day progresses, if the track starts
to break up - one very simple method of adjusting your car to cope with the changing conditions is to slightly
(and I emphasize the word slightly) raise ride height. Make adjustments on the spring collars of about 2 mm
per time.

Simple Rule 3
The higher the traction, the lower the ride height. If traction is very high (wet track, or good grippy clay or 'blue groove' conditions) your car will handle best (and resist traction rolling) with a lower ride height.
If the track is very grippy, and very rough - then you've got a typical suspension tuning situation - you need to compromise.

Simple Rule 4
Remember that changing tires can drastically change ride height. Always be aware that when you change your tires - you might have to re-adjust your ride height.
================================================== ====================================

Anti-Roll Bars

Anti-roll bars (or 'sway bars' as they are sometimes known) do one thing. Prevent, or inhibit a cars natural tendency to have chassis 'roll' or 'lean' towards the outside of a turn. A lot of the car weight wants to keep going straight ahead - thus throwing more weight onto the outside suspension and cause the whole car to 'lean' over.

The anti-roll bar prevents this lean by transferring some of the 'leaning force' across to the other side of the
car. Anti-roll bars (as the name suggests) help your car to sit 'flatter' through corners. Anti-roll bars are most useful in high grip, smooth track conditions - and probably in high-speed corners too.

In lower grip, or rougher conditions, anti-roll bars can take away grip from the end of the car you use them on, or simply prevent the suspension from working as freely as it possibly can.

Variables with anti-roll bars include the thickness of the bar, the location of the anti-roll bar mount on the suspension arm, and the location of the mounting joint on the anti-roll bar. Basically it's like this - to 'stiffen' the bar (or increase it's effectiveness) use a thicker anti-roll bar, mount the anti-roll bar further out on the
suspension arms, or mount the connecting joint further 'up' the bar (closer to the bend).

To 'soften' the anti-roll bar - do the opposite: use a thinner bar, mount closer to the center of the car,
or further out along the bar itself.

Note that for testing purposes, if you've got an anti-roll bar fitted to your car and you want to disconnect it, you can simply disconnect one end of the bar. That will remove the 'anti-roll' effect and leave you free to try without it. In racing situations, it's always safer to completely remove the anti-roll bar from the car if you don't
want to use it.

On a 4wd it is a very good idea to have an anti-roll bar available for the rear of your car. In my experience, 4wd cars use an anti-roll bar at least 50% of the time. 4wd electric cars are different from 2wd in that the saddle pack battery setup means that more weight is distributed further out along the chassis - thus increasing chassis roll.

On a 2wd you are not going to use an anti-roll bar anywhere near as often. You should be able to race very happily without any form of anti-roll bar on your 2wd (although having said that - a soft anti-roll
bar is a very good tuning tool to have - particularly on fast, smooth, high grip tracks.

I have personally never seen an anti-roll bar used on a Truck. Not sure why - perhaps trucks tend to sit
flatter due to different shock mounting positions. If you're a truck racer there's certainly no need to rush
out a pick up an anti-roll bar.

Other ways to get anti-roll: you can also get some kind of anti-roll effect from using different shock
mount positions. This topic is covered in Section (5). Remember though, if you change the shock mount
positions to get better anti-roll effect - you'll probably upset some other part of the suspension setup.

Suspension Droop

Suspension drop is adjusted by the use of shock travel limiters inside the shock, or by mounting the shocks in different positions on the tower or arm. Simply put, more droop is useful on a rough track, or sometimes in case of a slippery surface. More droop can also help your car to land better after big jumps. Less droop results in sharper handling and is best used on a smooth, high-speed track.
Less droop will help your car to change direction more quickly.


-----------------------------------------------------------------------------------------------------------------

Weight Distribution

When you're building your car, you should always do your best to have weight evenly balanced
across the car (from side to side). A car that is not balanced from side to side will struggle to jump,
accelerate or handle consistently. Side to side weight balance is not a tuning option. You should get it evenly balanced and forget it.

Altering weight balance from front to rear is both more easily achieved, and more useful as a tuning tool.
Basically it works like this:

More Weight to Front
More weight toward the front of the car equals more steering, and less rear grip.
Moving the weight up front will also tend to encourage your car to jump more nose down, and stop the car
from 'wheel standing' in extreme traction conditions. The easiest way to achieve a change in weight balance is by moving batteries forward in the chassis. Alternately, you can relocate electrical components further forwards but this is both difficult and time consuming.

Battery placement is the way to go.

More Weight to Rear
Moving weight toward the rear of the car does fundamentally the opposite. Adds rear traction, takes away steering, makes the car more stable under both acceleration and braking and can encourage
some degree of wheel standing in extreme traction or rough conditions. Rearward weight balance can also help the car to jump a little flatter if it is jumping 'nose down'. Altering weight balance to the rear is achieved in the same way - by moving batteries backwards within the car.

As an alternative - you might want to add more weight to front or rear without taking weight away from the other end (this is what happens when you move the batteries around). In this situation,
seriously consider adding some small lead weights (mag wheel balance weights) or coins. Add this
weight at the extreme end of the chassis, and as low as possible. Many 2wd cars and trucks have a
perfectly shaped hollow inside the front bulkhead for this purpose. Adding a little weight (probably no more than 10 grams) to the front of your car can add a little more steering, and help the car to jump
and little more 'nose low' but without taking away rear traction.
------------------------------------------------------------------------------------------------------------------
Steering Axis Inclination

Positive generally means it will increase the front end’s return-to-center characteristic and make the
front end difficult to turn.

The Most Sensitive Adjustments, and the most used by the Team Losi race team, are the number of washers
under the front
camber link ball studs and the anti-squat. See these two sections and try to familiarize yourself with the way
that these adjustments
affect the handling of the Triple-X-SCT
Ride Height is an adjustment that affects the way your truck jumps, turns, and goes through bumps. To check
the ride height,
drop one end (front or rear) of the truck from about a 5-6 inch height onto a flat surface. Once the truck settles into a position,
check the height of that end of the truck in relationship to the surface. To raise the ride height, lower the shock collars on the
shocks evenly on the end (front or rear) of the truck you are working on. To lower the ride height, raise the spring collars.

Both left and right collars should be adjusted evenly.
You should start with the front ride height set so that the front suspension arms are level with the surface. Occasionally,
you may want to raise the front ride height to get a little quicker steering reaction, but be careful as this can also
make the truck flip over more easily. The rear ride height should be set so that the truck comes to a rest at a height that
is right in between having the arms level and the dogbones level with the surface. Every driver likes a little different feel
so you should try small ride height adjustments to obtain the feel you like. We have found that ride height is really a
minor adjustment. This should be one of the last adjustments after everything else has been dialed in. Do not use ride
height adjustment as a substitute for a spring rate. If your truck needs a softer or firmer spring, change the spring. Do not
think that simply moving the shock collar will change the stiffness of the spring; it won’t!
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Front and Rear Static Camber Adjustment is normally set to 1/2-degree negative at ride height. However, adjusting the static
camber can increase or decrease front and rear chassis roll and affect the handling of your truck. Increasing negative
camber in the front will result in an increase in steering and improved handling through bumps. Increasing negative camber in the
rear will result in less side-bite and increased steering. Be careful not to add too much negative camber or the truck may start to
become difficult to drive.
Reducing negative camber in the front will result in a loss of steering, but smooth the steering response. Reducing
negative camber in the rear will result in an increase in side-bite and more forward traction. Typically a setting of between 1/2- and 0-degrees of negative camber on both the front and rear of the truck will result in a good, solid feel.

Rear Hub Camber Location is best set according the settings described in this manual. You should start with the inner hole in
the hub. This will typically make the truck go through bumps better. The inner hole may also give the feeling of more
steering. This steering generally comes from the rear end though. What this means is that the rear end of the truck may swing a bit
more — at times even sliding more. Moving it to the outer hole will tend to make the truck feel a bit stiffer. This results in the
truck accelerating straighter and also makes it a bit easier to line up for jumps.
Rear Camber Link Length can be another useful adjustment. It is virtually impossible to make a blanket statement for exactly
how the length of the camber link will affect the handling under all conditions. The following is our experience with how the length
of the camber link will typically affect the handling of the Triple-X-SCT. A longer rear camber link will usually result in more rear
traction. With a longer link, the truck can start to drive more square, or point-to-point. This can make it difficult to
carve corners at high speed. A shorter rear camber link will generally result in more steering from the rear of the truck due to
increased chassis roll. This can make it easier to change directions quicker, but can cause the rear of the truck to roll around if the
link is too short.
A shorter rear link will usually go through bumps a bit better than a long link as well.


Front Carrier Camber Location is another adjustment that is almost always run in the standard (middle hole) location. This
location keeps the truck flatter with less roll. The middle location also helps the truck stay tighter in turns with a more precise
steering feel. Moving the link to the inner hole will make the steering react slightly slower. The advantage to the inner hole is that
it can increase on-power steering and help the truck get through bumps better. Moving the link to the outside hole will result in
more off power steering and will make the steering react faster.


Washers Under the Front Camber Link Ball Stud can be added or removed. This is a very important adjustment on the
Triple-X-SCT You should get a feel for how the number of washers affects the handling.

Adding washers will make the truck
more stable and keep the front end flatter. Adding washers will give the truck more steering entering the turn but less steering on
the exit of the turn. Removing washers will reduce steering going into the turn and give more steering on the exit of the turn.

Front Camber Link Length is another adjustment that is difficult to make a generic statement for as it can have slightly
different results on various conditions. The following is a summary of how this adjustment will usually impact the
handling of the Triple-X-SCT. A longer front camber link will usually make the truck feel stiffer. This will help keep the truck flatter
with less roll, but can make the truck handle worse in bumpy conditions. A shorter front camber link will result in more front end roll.

This will increase high-speed steering and make the truck better in bumps. Too short of a front link may make the truck feel
twitchy or "wandery" — meaning that it may be difficult to drive straight at high speed.

Front Shock Location can be adjusted easily by simply moving top of the shock to another hole in the shock tower.

The standard location (second hole out) works best on most tracks. Moving the top of the shock out one hole will result in an
increase in steering and the truck will react quicker. Moving the top of the shock to the inside hole in the tower will slow the steering response time and make the truck smoother in bumps.

The bottom of the shock can also be moved in and out on the suspension arm. Moving the shocks to the inside hole
will result in more low speed steering and less high speed steering. A stiffer spring should be used when using the inside hole.

Moving the shocks to the outside hole will require less shock limiters and will give more high speed steering and less
low speed steering.

Rear Shock Location can be changed just as easily as the front. Again, the standard location is the best place to start for most tracks. Moving the top of the shock in on the shock tower results in less side-bite (traction in corners) and makes the truck
smoother in bumps. Moving the top of the shocks to one of the two outside holes will give the truck more forward traction and
side-bite and helps keep the truck from bottoming out on big jumps.

A softer spring should be used if the shocks are mounted in one
of the two outer holes in the tower.

Rear Anti-Squat is one of the two most commonly-used adjustments of the Triple-X-SCT washers under the front
camber link ball stud being the other. The Triple-X-SCT , as built per assembly instructions, has 2o of anti-squat. Adding the shims under the front of the pivot block will result in 4o of anti-squat. This will result in less side-bite, which will cause the truck to have more
steering from the rear end. More anti-squat will also make the truck get more air off of large jumps. Rear anti-squat is another adjustment that you should play with to get a feel for the different handling characteristics.


Rear Hub Spacing can be adjusted by moving the spacers at the front and rear of the hub carrier. You will probably find that the
middle (standard) location works best on just about every track. Spacing the hub back might help on large, high-speed, outdoor
tracks. Spacing the hub forward might help on tight, indoor tracks.
Battery Location is sometimes overlooked, but can be a useful adjustment. Start by running the battery spaced in the middle.
Moving the battery back can improve rear traction on slippery tracks. Moving the battery back too far can cause the
rear end to swing though turns on some tracks.
This is a result of having the weight too far back.

Tires

Tires are always the first element in setting up a car. If you've got the right tires, you're 90% there.

Springs

Stiffer Stiffer springs make the car feel more responsive, more direct.
They also help the car jump a little better and higher.
Stiff springs are suited for high-traction tracks, which aren't too bumpy.
Softer Softer springs are better for (mildly) bumpy tracks.
They can also make the car feel as if it has a little more traction in low-grip conditions.

Stiffer Front The car has less front traction, and less steering. It's harder to get the car to turn, the turn radius is bigger and the car has a lot less steering exiting corners.
The car will jump better, and maybe a little further.
On very high-grip tracks, it's usually beneficial to stiffen the front, even more than the rear. It just makes the car easier to drive, and faster.
Softer Front The car has more steering, especially in the middle part and the exit of the corner.
Front springs that are too soft can make the car hook and spin, and they can also make it react sluggishly.
Stiffer Rear The car has more steering, in the middle and exit of the turn. This is especially apparent in long, high-speed corners.
But rear traction is reduced.
Softer Rear The car has generally more rear traction, in turns as well as through bumps and while accellerating.

Damping

Heavier Thicker oil (heavier damping) makes the car more stable, and makes it handle more smoothly.
It also makes the car jump and land better.
If damping is too heavy, traction could be lost in bumpy sections.
Softer Soft damping (and springing) is better for shallow, ripply bumps.
It also makes the car react quicker.
Damping should always be adapted to the spring ratio; the suspension should never feel too 'springy' or too slow.
Heavier Front The turn radius is wider, but smoother. The car doesn't 'hook' suddenly.
The car is easier to drive, and high-speed steering feels very nice.
Softer Front The steering reacts quicker.
More and better low-speed steering.
Heavier Rear Steering feels quick and responsive, while the rear stays relatively stable.
Softer Rear Feels very easy to drive, the car can be 'thrown' into turns.
More rear traction while accellerating.
If one end of the car has slightly heavier damping than the other, then that end will feel as if it has the most consistent traction and the most stable when turning in and exiting corners.
A car with slightly heavier rear damping, or slightly lighter front damping will feel very stable turning into corners on bumps or whoops sections. It won't feel 'touchy' at all.

Caster

More More caster aids stability, and handling in bumpy sections.
Less Less caster increases steering drastically.
Steering feels much more direct, the car turns tighter and faster.

Ride Height

Higher The car feels better in bumps, and jumps better.
It can feel tippy, or even flip over in high-grip conditions.
Lower The car feels more direct, and it can potentially corner a bit faster.
It's also harder to flip the car over.
Lowering one end of the car, or putting the other end higher up, gives a little more grip at the lowest end, but try to avoid big differences in ride height between the front and the rear.

Wheelbase

Shorter A short wheelbase makes the car feel very nimble, and good in tight turns.
This is a good idea for very small and tight tracks, without big jumps or bumps.
Longer The car becomes a lot more stable, adn better in wide, high-speed turns.
This is good on wide-open tracks.

Anti-Squat

More More anti-squat generally makes the rear of the car more sensitive to throttle input.
The car has more steering while braking, and also a little more powering out of corners.
On high-traction tracks, it may feel as if the car momentarily has more rear traction accellerating out of corners.
A car with more anti-squat can also jump a little higher and further, and it will soak up bumps a little better, off-power.
A lot of anti-squat (4° or more) can make the car spin out in turns, and make the rear end break loose when accellerating.
Less Less anti-squat gives more rear traction while accellerating on a slippery or dusty track.
It also gives more side-bite.
Less anti-squat will make the car accellerate better and faster through bumpy sections.
Very little anti-squat (0° or 1°) makes the rear end feel very stable. It also makes power sliding a lot easier.
Note that anti-squat only works when you're accellerating or braking, it does absolutely nothing when you're coasting through turns.
The harder you brake or accellerate, the bigger the effect of anti-squat is.

Shock Pistons

The assumption is made that if pistons are changed, the viscosity of the oil is also adapted, to give the same static feel. (Same low-speed damping)
Smaller Holes Smaller holes mean more 'pack'. Pack means the damping gets very stiff, or almost locks up, over sharp bumps, ruts, or landing off jumps.
Small holes are good for smooth tracks, with big jumps or crummy jumps with harsh landings.
Bigger Holes Bigger holes mean less pack. The point at which the damping gets stiff (where the shock 'packs up') occurs a lot later, at higher shock shaft speeds.
Big holes are very good for bumpy tracks. The car is more stable and has more traction in the bumpy sections. It won't be thrown up over sharp bumps, the suspension will soak them up a lot better.

Smaller holes in front The car jumps very nicely, a little more nose-up.
It feels easy to drive.
Bigger holes in front Can give a subtle feel of more steering and more consistent front end grip if the track isn't perfectly smooth.
Always use the same, or about the same shock pistons front and rear. Big differences in pistons make the car feel inconsistent, and not very smooth.

Lower Shock Mounting Location

Bear in mind that changing the lower shock mounting location changes the lever arm of the shocks on the wheels.
So mounting the shocks more inward makes the suspension softer at the wheel, and mounting the shocks more towards the outside makes the suspension stiffer.
Front more inward More low-speed steering.
Usually makes the car very hard to drive.
Front more outward Makes the car very stable, but it has a lot less low-speed steering.
Rear more inward Makes the car soak up bumps a little better, and can make the car corner a bit faster.
Can be good for bumpy, low-grip tracks, but general stability is greatly reduced.
Rear more outward Feels very stable.The way to go for high-grip tracks.

Upper Shock Mounting Location

More Inclined Has a more progressive, smoother feel.
More lateral grip.
Less Inclined
(More Vertical) More direct feel;
Less lateral grip. (side-bite)
generally a bit better for jumps and harsh landings.

Front more inclined than rear Steering feels very smooth.
A little more mid-corner steering.
Mounting the rear shocks very upright can result in the rear end sliding in the middle of the turn, especially in high-speed turns.
Rear more inclined than front Feels agressive turning in.
The car has a lot of side traction in the rear, and the turn radius isn't very tight.


Camber

Camber is best set so the tires' contact patch is as big as possible at all times. So with a stiff suspension you'll need less camber than with a soft one.
If the tires wear evenly across their contact patches, camber is about right.
On really bumpy tracks, adding a little more negative camber (2 to 3 degrees) can help traction and reduce the chances of catching a rut and flipping over.

Toe

Front Toe-in Stabilizes the car in the straights, adn coming out of turns.
It smoothes out the steering response, making the car very easy to drive;
Front Toe-out Increases turn-in steering a lot.
But can make the car wandery on the straights;
Never use more than 2 degrees of front toe-out!
Rear Toe-in Stabilizes the car greatly. It makes the rear end 'stick', but more toe-in makes the difference between sticking and breaking loose bigger.
Rear Toe-out Rear toe-out is never used. It makes the rear of the car very, very unstable.

Anti-Roll bar

Anti-roll bars are best used on smooth, and high-traction tracks only.
If you must use one on a bumpy track, try to use a very thin one.
Adding an anti-roll bar, or stiffening it, reduces traction at that end of the car. So it feels like the opposite end has more grip.
If the track is smooth enough, it also makes the grip level feel more consistent.
Anti-roll bars reduce body roll in turns, so they make the car feel more direct, and make it change direction quicker.

Stiffer Front An anti-roll bar at the front of the car reduces low-speed steering. The turning radius will be larger, but very consistent.
It reduces 'hooking' by preventing front end roll.
The car will have more rear traction in turns.
Stiffer Rear Adding an anti-roll bar to the rear of the car gives more steering. the car steers tighter, also at low speeds.
On a very smooth track, it can make powersliding easier. It can also make powering out of turns and lining up for jumps a little easier.

Ackermann

More
(Bigger difference in steering angle
between the two font wheels) More Ackermann makes the steering more consistent, and smoother.
It just feels right, also at low speeds and in tight turns.
Less
(Smaller, or no difference in steering
angle between the two font wheels) Less Ackermann makes the steering more agressive at high speeds.
The car turns in more agressively.
It doesn't work well when either traction or cornering speeds are low.

Internal Travel Limiters / Droop / Downtravel

More
(less droop/downtravel) The car changes direction faster, and corners flatter. It feels generally more responsive.
Adding a lot of travel limiters is only advisable on smooth tracks.
Less
(more droop/downtravel) Less internal shock spacers give better handling on bumpy tracks, and more and more consistent traction on difficult tracks.
The car also land better after jumps.
The end with the least downtravel will feel the most stable, and the most direct. But try to keep a balance (front and rear end droop about the same), especially on low-grip tracks.
Adding more internal travel limiters is a very effective way of reducing traction rolls, if not the most effective way.

Wings

Front Adding a front wing, or increasing front downforce increases steering at speed, which almost always makes the car feel very, very agressive and difficult to drive.
Rear Adding rear downforce by changing to a bigger wing, or mounting he wing higher or at more of an angle increases rear traction at speed.
This can be very useful on slick tracks with fast, sweeping corners.

Pinion/Spur

Smaller Gear Ratio
(bigger number means smaller ratio) More punch and accelleration.
More runtime.
Lower top speed.
Bigger Gear Ratio
(smaller number means bigger ratio) Less punch, but more top speed.
Less runtime.
Smaller Pinion Gear Smaller gear ratio
Bigger pinion Gear Bigger gear ratio
Smaller Spur Gear Bigger gear ratio
Bigger Spur Gear Smaller gear ratio
Overall Ratio Overall Ratio = (Spur/Pinion)*Internal Gearbox Ratio
Rollout
(mm/rev) Rollout = (Pi*Tire Diameter)/Overall Ratio

Glossary of Terms

Understeer- Describes a lack of front grip. If you turn the wheels and the car still wants to go straight or
doesn’t turn as sharply as desired, that condition is known as understeer. It is also known as “pushing”

Oversteer- Describes a lack of rear grip. This occurs when the rear of the car wants to come around or
spin out while cornering. A car that has this trait is said to be “loose”.

Roll Center- Refers to both the camber locations and the mounting point for the suspension arms. By
adding or removing shims from under the camber ball stud or raising or lowering it in a shock tower,
you will change the rate of camber change. By changing the height of the suspension mounts, the weight
transfer and roll rate of the car is altered.

Camber- The angle of the tire in relation to the ground. A tire that is perfectly up and down has 0-degrees
of camber. A tire that has the top leaned away from the centerline of the chassis is said to have positive
camber. A tire that has the top leaned in towards the centerline of the chassis has negative camber.

Caster- Refers to the angle of the front axle/steering knuckle in relation to the ground.

Toe In/Out- Looking down at your car from overhead, if the front part of your tires is closer than the rear,
that is toe in. If the rear part of the tire is closer, that is toe out. By using toe-out on the front of your car,
it will initiate a turn more aggressively. Toe in is not used on the front. On the rear of the car, toe in increases
rear grip. Toe out is never used on the rear of the car.

Shock Oil- A viscous fluid that is used inside the shock body to vary the dampening rate of a shock. Available
in a variety of viscosities, a thicker oil will resist piston movement more, while a thinner oil will allow a
piston to pass more freely. Using thinner oil will also allow the car to be more compliant, handling
bumps and inconsistencies in the surface better.

Traction Roll- A condition that occurs on extremely high-grip surfaces where a car will flip or roll over
when cornering.

Ackerman- Describes the difference in the angle of the inside and outside tires in relation to the chassis
while cornering.

Bump-Steer- Refers to the steering geometry changes that occur when the suspension is
compressed.

Pack- How firm or soft a shock feels when compressed with a specific shock oil and piston

Droop- The down travel of a suspension arm once it is fully extended.

Transmission

Gear Ratio
The primary tuning option relating to your car's transmission is the ability to change gear ratio by using different spur gears or pinions. Before we talk about the effect of gear ratio changes, let's spend a moment sorting out the terminology.

Gear ratios are most often quoted in the form "7.8 to 1". This can be represented in writing as 7.8:1. This means that the motor must rotate 7.8 times for the car's driven wheels to complete one full revolution. Gear ratios can be calculated by dividing the number of teeth on the spur gear by the number of teeth on the pinion and multiplying the result by the internal ratio of the gearbox. Most instruction manuals should tell you the internal ratio of your car's gearbox

The formula for calculating gear ratios looks like this:
(# teeth on spur / # teeth on pinion) X Internal Gearbox Ratio = Gear Ratio

We've already seen how gear ratios can be represented as numbers (e.g. 7.8:1). The tricky part is in describing ratio changes in general. If you put a bigger pinion on the car, the ratio will change to a small number (say 7.4:1). While the numerical figure has become smaller, the actual gear ratio 7.4:1 is said to be a 'higher' ratio than '7.8:1'. Similarly, moving to a smaller pinion will produce a 'lower' ratio (say 8.2:1). Without wanting to confuse you, changing the spur gear has the opposite effect. A smaller spur gear will result in a 'higher' gear ratio, and a larger spur gear will give you a 'lower' gear ratio. Confused? Stay with me.

Gear ratio changes do a couple of things. Let's look at both the 'lower' and 'higher' gear ratios separately to see what we find.

A lower gear ratio will mostly give you more run time and more acceleration. It's also generally easier on your motor.

A higher gear ratio will generally give you more top speed, and less run time. It's also tougher on your motor. Once you get to a certain ratio point (lets call it the 'optimum ratio') continuing to change to a higher ratio will do nothing but damage. It will result in your motor overheating and being damaged, and in extreme cases, your car may actually go slower.

How's that? Did you understand it all? Have another read, and think about it carefully. Then look at this simple chart, which might help make things clearer.

= smaller spur = higher gear ratio = gearing up = more top speed = less acceleration = less run time = harder on motor.

= bigger spur = lower gear ratio = gearing down = less top speed = more acceleration = more run time = better for motor.

Losi Truck Spur Colors

76 Black
78 White
82 Yellow
84 Purple
86 Red
88 Green
90 Orange
92 Blue
94 White

Pinion 84t Spur 86t Spur 88t Spur 90t Spur
18 11.34 11.61 11.88 12.15
19 10.74 11 11.25 11.51
20 10.21 10.45 10.69 10.94
21 9.72 9.95 10.18 10.41
11 is ideal for 2.43 tranny


Differential

Your buggy or truck gearbox (transmission) is fitted with a differential. The purpose of the differential is to allow the wheels to turn at slightly different speeds. This is necessary to help the car turn corners. When you car turns a corner, the outside wheel has to travel further than the inside wheel - thus it needs to turn slightly faster to keep up. Differentials (or diffs) in model cars are typical of two kinds. Entry-level cars often use 'gear diffs' while more competition-oriented manufacturers use 'ball diffs'. Both work in the same way, and largely achieve the same thing.

Ball Diffs are, however, slightly adjustable. By slightly increasing or decreasing the tension on the diff screw (see your instruction manual for details on how) you can make the diff 'looser' or 'tighter' A tighter diff is one that is hard to turn. Tighter diffs help your car to put down power coming out of corners and in a straight line, while looser diffs help your car to turn corners better. If you loosen the diff too far, it will allow the diff to slip. Make no mistake - this is a bad thing. Diff slip damages the components of the diff and is inconsistent. Your instruction manual will describe how to tell if your diff is slipping or not. I never recommend running any diff slip - that's what a slipper clutch is for (what's a slipper clutch? Read on).

About The Differential

Never allow the diff to slip; that’s what the slipper is for. Before trying to adjust your diff, you need to
tighten the slipper until the spring is fully compressed. Next, hold the spur gear and right rear tire, then try turning the left rear tire
forward. It should be very difficult to turn the left rear tire. If the tire turns easily, the diff is too loose. To tighten the diff, line up
the slot in the diff screw with the groove in the left outdrive. Place the 1/16” Allen wrench through both of these slots. This will
lock the diff screw and the outdrive together. While holding the Allen wrench in place, turn the right rear tire forward about 1/8 of
a turn. Check the differential adjustment again and repeat the tightening process as necessary until the differential is no longer
slipping. The final differential adjustment check should be made by placing the truck on carpet, grass, or asphalt and punching the
throttle. The differential should not slip. If it does, tighten the diff in 1/8-turn increments as described above until the slippage stops.
Once the diff has been adjusted, it should still operate freely and feel smooth. If the diff screw starts to get tight before the diff
is close to being adjusted properly, the diff should be disassembled and inspected; you may have a problem with the differential
assembly. Refer to the assembly instructions to ensure that the diff is properly assembled and that all parts are properly seated in
the assembly.
There are a few things you should know about differentials. First, when rebuilding your diff, you should always
replace the small, 4-40 locknut. Second, after the diff has been built for a couple of hours, or been run a time or two, it
is not uncommon for the balls to seat into the rings and create a slightly loose adjustment. So, after your first run, check
the adjustment to avoid slippage. Third, remember: Never let the diff slip. Doing so can damage the diff balls, rings, and
gear. Always make sure that the slipper will slip before the diff.

Slipper clutches
Slipper clutches are designed to do exactly what you might think by their name - slip. When you jam on the throttle, the slipper clutch is designed to slip a little before transmitting all that horsepower to your overstressed rear tires. The slipper clutch (or 'clutch' as it's usually known) helps when the track is slippery, or rough, or when you bolt in an enormous motor. The best way to set your clutch is to loosen it right up ('back it off' is the term you'll mostly hear) and place your car on the main straight at your track. When you pull the trigger to accelerate away, the car should move slowly off, with the transmission emitting a loud 'whining' noise. That's the clutch slipping. Now slowly tighten the clutch about 1/2 a turn at a time (trying a full throttle take off after each adjustment) until the clutch only slips for about 3 feet. This is going to be a fairly good setting for most tracks. If the track has particularly high traction, or if you're not having any problems with too much wheelspin - you might even like to run the clutch tighter still. I would recommend against locking the clutch entirely. Just tighten it enough so that there is no slip on acceleration. This will still allow the clutch to slip when your car comes down hard off a jump - or through rough sections of the track - thus protecting the transmission.


Adjusting the Slipper
the slipper adjustment nut four full turns (e.g., 360 degrees x 4) to return the adjustment to the setting originally described in the
assembly instructions. To make the final adjustments, place your truck on the racing surface and give the truck full throttle. The
slipper should slip for one or two feet at the most. If the slipper slips for more than two feet, you’ll need to tighten the adjustment
nut. If the slipper doesn’t slip for at least one foot, back off the adjustment nut 1/8 of a turn and retry. If you can’t hear the slipper
when you punch the throttle, hold the front of the truck with the rear wheels still on the track surface and give the truck full
throttle. The truck should push against your hand with reasonable force and the slipper should slip slightly.
Don’t expect the slipper to make up for poor driving. You still have to use your throttle carefully. The slipper will, however,
give you a little help coming off corners and landing jumps.
When the track is really rough, rutty, or has a lot of killer jumps, you may want to consider installing a Hydra-Drive
unit. When using the Hydra-Drive, the slipper adjustment should be set a bit looser so that the spur gear is easier to
rotate while holding the right rear tire. Use the same method of checking adjustment on the Hydra-Drive as you would
on the standard friction slipper. Do not run the Hydra-Drive too loose; it will build up heat and eventually damage the
seals. The standard fluid should be used most of the time in the Hydra-Drive. This kit has a different type of slipper that
cannot be used with the Hydra-Drive as it is currently assembled. However, a Hydra-Drive unit can be fit to the shaft by
replacing the gear and outside aluminum slipper back plate with the Hydra-Drive spur gear, gear plate, Hydra-Drive
unit, spring, etc.







Tires

The choice of tires is probably the single most crucial factor in getting your car to handle well. If you choose the wrong tires, there is often very little you can do to retrieve the situation. We'll cover a number of variables at work in determining the correct tire choice - hopefully helping you to 'guess' correctly the first time you run on a new track or surface. Let's initially concentrate on rear tire choice - front tires will be considered separately towards the end of this chapter. I won't treat truck tires differently - most of the tires listed here have an equivalent in the truck tire range. You just need to check with your retailer as to the approximate truck equivalent.

Compound

The 'compound' or 'softness' of the tire can often have a major impact on it's performance. Each different tire manufacturer has their own range of tire rubber - giving different names to each different compound.

The first thing to realize about tire compound is that softer is not necessarily better. The new generation 'super soft' compounds work only in certain situations. Super soft tires should be used when the track reaches 'blue groove' conditions. This is when there is practically no dust on the racing surface - just a rock hard, concrete like surface where the racing line comes up 'blue' from deposited rubber. In these conditions tire traction is mostly generated by the rubber compound in use and it is then that super soft tires should be used.

In general, the soft compound tires will perform best. Well packed track surfaces with some loose material on the surface are particularly well suited to these types of tires. Dusty conditions also suit soft tires. Medium compound tires can be most effectively used when the track condition is bad. When predominantly loose material is on the surface, when the track starts to break up into 'rubble' or in moderately wet conditions, medium compound tires should be your first choice.

Hard tires are rarely used. Only if the track is particularly wet/muddy, or if the track surface is grass, or some similar multi-surface, should hard compound tires be used.

Tire Profile

The profile or 'carcass shape' of the tire is another crucial element in choosing the right tire for your car and track conditions. Tire profile can be roughly categorized into two alternatives - 'square' or 'rounded'. There are other profiles, and some tires which fit in between the two extremes, but let's not get too carried away.

A square tire is one which has a flat 'crown'. That is, a tire which will stand on it's own on your pit table and where most of the tire surface sits in contact with the table surface. Square profile tires almost always provide excellent forward traction (due to large contact patch).

In smooth track conditions, square tires can also provide excellent 'through corner' traction. These tires suffer most when tracks start to break up, or in conditions where the car is constantly sliding sideways. In these types of condition square tires can slide unpredictably, or can 'catch and edge' in ruts and holes - causing the car to flip, or get out of shape.

A 'rounded' tire is extremely predicable through corners, and excellent in rough, rutted conditions. Whilst not so good at generating forward traction in smooth conditions, the rounded tire is almost universally chosen when the going gets rough

There are also a number of tires that can be considered to be 'in between'. It's not really rounded, yet not completely square and is often a good compromise tire.

Foam Inserts

Most rear tires (with exception of 'hard' compound tires) will require the use of a foam insert. In most cases, these will be provided with the tires. Foam inserts can generally be used as supplied, with just a minor modification. Cutting the square edge of the outside of a foam insert can produce a slightly 'softer' tire sidewall and slightly more 'rounded' profile when using square tires. This can help to make the tires more consistent through corners, and less likely to 'grab' and roll in rutted conditions.

Softer tires also require more 'dense' foam inserts. If you are planning on using the 'super soft' compound tires, you should try to make sure that you have a set of 'dense' foams at your disposal.

Front tires too, will often require foam inserts. In particular soft, and super soft compound tires should always use inserts. You can, however, sometimes get away without inserts in a medium compound tire. Running no insert will result in a slightly 'softer' tire that behaves almost like a tire compound in between medium and soft. Sometimes worth a try if you can't quite settle on the right front tire compound.

Wow....nice write-up

You should add this to the "tune with camber links" thread. A lot of good info there also.

Confused a little on your Losi buggy spring rates though....my packages of springs don't match up to your rates.

Edit...my bad. Was looking at 5450-5458 15mm springs

Thank you, I will be coming back to this thread for reference as I progress in setup, I hope this gets a sticky or something so it doesn't get lost!

its all here http://users.telenet.be/elvo/ there is a quick reference guide that you can print out

yes, some of the info did come from there, but there is a lot more info here than there.

definately some great info here! thanks for posting!

Some more you guys can bright to the track, mainly those not willing to bring the laptop: http://www.petitrc.com/index.php?page=setup_guide

Thanks for the replies guys!
I'll be adding and organizing as time goes on.

Great Thread

+1^

+2 ^