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Old 07-30-2011 | 07:49 PM
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slim jim
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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.
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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.
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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.
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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.


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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.
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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.

Last edited by slim jim; 07-31-2011 at 07:08 AM.
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