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This is a place to share knowledge related to 1/12th scale racing. It is not to be used for conversations.

KITS:
Click links to go to manufacturer product page. If any are missing please add them!

TIRES:
Pre-mounted tires readily available in the US:
Pre-mounted tires readily available in the Europe:
  • Hot Race ??

Gluing your own donuts:
https://www.youtube.com/watch?v=hm7z1rz-74s - Special thanks to Edward Pickering!
Truing tires:
https://www.youtube.com/watch?v=8wqHOLWq6Uc - Special thanks to Edward Pickering!

The following information came from HERE, with some editing and information added. Thanks Christian!

THIS MAY NEED UPDATING FOR THE NEW BLACK CRC CARPET

Brands:
BSR, CRC, Jaco:
Pro One is no longer selling to the public, but it and the brands above are all mounted by BSR and use the same foam. The nomenclature of the BSR vs Jaco/CRC is a little different in a few instances but is otherwise the same. The BSR foam consists of three families, and can be identifed as synthetics, naturals, and blends.

Synthetics - The old school, light weight, easy to true "dry feeling" tires. These include tires like CRC/Jaco Yellow (BSR White), Black, Gray, etc. These tires offer the highest wear rate and lowest grip. Many racers continue to use these nder high bite conditions.

Naturals - These tires are usually the best alternative for low bite and asphalt. They include Pink, Magenta, Double Pink, Lilac (BSR Team Purple), Purple, and other tires. These tires provide a ton of grip, but tend to get sticky in high bite conditions. This rubber does not wear as easily, and the cars will pick up gunk and fibers from the carpet under most high bite conditions. This is especially bad if the humidity is high.

Blends - These are the tires most people run today. They were initially called "JFT foam" by some, as it was believed that the tires were the same as the JFT tires. We can divide the blends further into two groups: high rubber and low rubber content. The high rubber would be the new rear Orange and Red from the BSR family, and the low rubber would be the Green and Blue varieties. When, asked about the difference, John Foister from BSR Tires said they came from the same "family" of foam, but they offered different grip. According to John, the Green/Blue has more bite than Orange/Red, but from track testing Oranges offer more bite than Green (being equivalent to in hardness) when the grip is high and absolutely no grip when it is lower. The Orange foam has a denser pore structure and the tire is not as prone to chunking. It is also important to note is that BSR Blue rears are not the same as the BSR Blue fronts!

JFT:
JFT stands for Japan Foam Tire. They started the new wave of foam tires we are all using now (Blue/Blu, Green/Greene, Dbl Blue, etc). These tires are a little different than the BSR tire family, but work in very similar conditions. They offers four varieties A (asphalt), C (carpet), S (???), and R (???). This does not mean that those types only work on that surface, but this is what they recommend.

JFT uses the same foam for fronts and rears if the color is the same.

A: Used on asphalt, considered close to the natural rubber variety and are named consistently with other natural tires.
C: Used on carpet, considered a blend.
S: Used on carpet?, tires are ???
R: Used on carpet?, tires are ???

For setup, the JFT foam seem to generate more bite than the BSR, therefore the car tends to be a little more aggressive.

Ulti:
Ulti is another Japanese brand that offers an array of compounds. They have their own way of rating tires, and are difficult to equate to other brands. They have 4 different varieties, each in varying degrees of hardness.

J: High rubber content tire, similar to Pink/ Magenta. Soft would be close to a pink. These offer the most bite and are great for asphalt/carpet front tire. (J hard being very popular)
X: "Balanced" blend, similar to JFT Blue/ Green. Soft is equivalent to Green, medium to Blue in hardness. Great for carpet!
Y: High synthetic blend with lower grip, and is not a very popular variety.
Z: A very expensive "special" foam that is supposed to be magic on asphalt. Only make it in soft shore.
European tires:
There are many great European foam tire brands that use their own types of foam, as well as traditional foams. SOmeone with more knowledge about them will need to fill this in!

Tire Diameter:
If you are racing on carpet, you have to evaluate how much grip your track has. If your track is low to medium grip, you can run bigger tires. If you are on higher bite you have to cut them smaller, there is simply no way around it. Bigger tires are needed for asphalt, especially in the rear. The larger tires provide much needed lateral bite.

Carpet (mm):
Low - Medium Bite
Front: 42.0 - 42.5
Rear: 42.5 - 43.00
Medium - High Bite
Front: 40.5 - 41.0
Rear: 41.5 - 42.0
Big Race
Front: 39.5 - 40.0
Rear: 40.5 - 41.0
Asphalt (mm):
Parking Lot
Front: 43.0 - 44.0
Rear: 44.0 - 45.0
Prepped High Bite
Front: 42.0 - 43.0
Rear: 43.0 - 44.0

Tire Saucing:
Most facilities have moved towards odorless traction additives such as SXT. Some of additives evaporate very quickly and some do not. This seems to be something that is also dependent on tire compound and ambient temperature. For example, saucing a Green compound seems like it never dries, especially when tjhe temperature is lower. We have found that wiping the tires off 15 minutes before we go run allows the sauce to cure, which makes the car come in much quicker with Green rears. Blue compounds on the other hand, do fine when wiped off right before hitting the track.

Saucing half front and full rear is a good initial starting point. If the front of the car is too agressive you can sauce les than half, or for a shorter amount of time. On black carpet the car may be numb to sauce changes, either a long or short sauce can produce very similar handling.
Tire Fuzzing:
In conditions of increasing grip, foam tires will somewtimes get sticky and pick up fuzz and debris from the track. This is highly dependent on the rubber sedan tire that is being run at your local track and the compound/ type of foam you are running on you car. The softer the sedan tire and the harder/higher rubber content in your foam tire, trouble with fuzzing seems more likely to occur.

There are ways to get around fuzzing under most conditions, and usually involves the selection of the correct foam compound. The more fuzz you get, the softer/lower rubber content you want to run.

Examples:
Problem: Car fuzzes with Lilac/Team Purple fronts and car starts pushing.
Solution: Use a softer front tire and or different family of foam. Replace it with Blue or Double Blue front. Alternatively you can sauce the front tires harder and tune the car for less front end bite.

Problem: Car loses rear bite 6 minutes into the run. Blue rear tires look almost clean but have small carpet hairs.
Solution: Use Green rear tires. The softer compound wears instead of getting sticky, minimizing fuzz. Possibly a longer sauce will prevent fuzzing.

Tire Selection:
Starting out, pick 2 tire compounds for the front and rear. The following should have you covered 99% of the time.

Rear - Green and Blue (BSR) or Green and Light Blue (JFT)
Front - Blue and Double Blue (BSR) or Blue and Dark Blue (JFT)

You may wonder about other compounds out there and if they might be better, trust me, they probably won't be. Even if there are other tires that can be as fast, the synthetic family wears out really fast and the high natural rubber will probably fuzz on you over an 8 minute run. The blends family seems to be the most versatile foam type available today. They last awhile, and sticking to them will make your process of tire selection simpler.
Tire Charts:
BSR/CRC/Jaco



Contact



Corally



JFT (Japan Foam Tire)



Ulti



Enneti (Xceed)



ELECTRONICS:
ESC:
As of now, ROAR is staying 1S (3.7V nominal; 4.2V fully charged) for 1/12. There are many 1S ESC's with a built in BEC so nothing else is required to power the receiver and servo.

If you don't want to lock yourself into a 1S specific ESC, you do have other options! It is possible to use your 2S ESC without a booster or receiver pack, and the ESC simply supplies the lower voltage. If that does not appeal to you, you will need to use an Rx pack or booster. The Rx pack and booster will both supply the receiver with a higher voltage than the 1S pack.

If you decide to use an Rx pack, MAKE SURE TO REMOVE THE RED WIRE FROM THE ESC PLUG THAT GOES INTO THE RECEIVER!!!

If you choose to use a voltage booster, it works exactly how it sounds. Instead of plugging the ESC into the receiver, it plugs into the booster, and the booster plug goes to the ESC, supplying the higher voltage.

1S ESC:
If there are any missing please add them!!

If anyone would like a need for a chart comparing the ESC's specs PM fenton06 and I'll get one made and put in here!
DISCONTINUED 1S ESC:
If there are any missing please add them!!


If anyone would like a need for a chart comparing the ESC's specs PM fenton06 and I'll get one made and put in here!

Voltage Boosters:
If there are any missing please add them!
Servos:
BODIES:
Black Art (CRC - US Dist):
  • Audi R8C - BA002 - .020 Thick



  • Black Market (Mohawk 12) - BA005 - .020



  • Lola B10 - BA006 - .020 thick
  • Toyota TS030 - BA008 - .020 thick

    Lola - black/red, TS030 - green/pink


PROTOForm:

Reflex Racing/RSD:

SUSPENSION ADJUSTMENTS:
Pan Car Front Suspension Tuning:
DISCLAIMER : The following tuning advice was written based on the tuning experience of the author and may not hold true for all cars, drivers, or surfaces. In the end the best tuning advice is to experiment and make changes one at a time so you can track your changes and find the car balance that works best for your driving style. One real world test is worth a million ‘expert’ opinions.

Front End Type:

All popular modern pan car front suspensions are very similar, with a few exceptions such as Speedmerchant New School but most of the info in this wiki applies to them as well. For the most part, they consist of a rigid bottom arm, an upper A-arm, and a kingpin with a spring. There are different flavors of this general design, such as the CRC Dynamic Strut that uses a threaded kingpin and upper pivot ball instead of the Associated style that uses a kingpin that goes through the entire steering knuckle assembly, but their operation is the same with the rigid lower arm and the upper arm controlling the arc of movement as the suspension is compressed.

Assembly:

More so than in almost any other part of the car, the front suspension of your 1/12 car must move absolutely free. Reamers and hobby knives are important here, as any binding will cause the car to corner unpredictably. A little play in the suspension is a good thing, and racers will often find that ‘worn in’ suspension pieces function a little better than new.

Springs:

Besides tires, spring rate is the most important part of deciding how your car will handle through corners, but are somewhat complicated. As a general rule of thumb, a very hard front spring will have somewhat less steering grip than a softer spring with the same suspension setup and tires, but not as much as in other classes such as touring or offroad. On carpet, springs of different tension can be used to tune how your car will maintain or lose energy through corners with the following general rule of thumb:

Hard Spring (0.55mm or harder): Less overall steering, quick reaction to driver input, less on power steering, harder turn-in with potentially lazy mid-corner and exit.

Soft Spring (.45mm): More overall steering especially at low speed, slightly slower reaction to driver input, more on-power steering, less aggressive turn-in but can ‘hook’ and give better mid-corner and exit.

It is worth noting that front springs from different suppliers are often very different, in both height, wire thickness, and coils for a given spring height meaning that a “medium” spring from one manufacturer may be the “hard” spring for another. To make accurate changes you may want to use one spring maker and stick with their line.

Another aspect to pan car springs is that they can get “blown out” and collapse, no longer as stiff or as tall as they were. These should be replaced with fresh springs to ensure consistent handling.

Dampening:

This is generally a minor adjustment, but adding dampening tube fluid to the front kingpins of a 1/12 car can give it a little more initial steering. Often unusual compounds see use here, such as Losi Smart Diff Grease or Associated Green Slime being a popular front kingpin lube.

Caster and Reactive Caster:

Caster is the angle of the kingpin, almost always angling back to the rear of the car, with a typical range from 0-10 degrees. Increasing your caster will typically result in less turn-in but a little more control, more steering exiting the corner, and somewhat increased straight-line stability with less tendency to wander because a wheel running caster will tend to straighten itself. Less caster will usually give you more off-power steering, but often with correspondingly less on-power when accelerating out of the corner.

Running reactive caster attempts to use both of these aspects to increase overall steering: when the car loads up on the outside front tire, the caster angle decreases, increasing the front end ‘hook’ as you enter the corner and then giving you the high caster on-power steering as you exit and weight is transferred off the front end. More reactive caster means more overall steering, but can mean you may have to adjust your driving style to drive more ‘ahead of the car’, needing to predict where the front end will grip.

As grip increases, less reactive caster is the normal tuning change made to keep the front end of the car from gripping too hard and oversteering and prevent traction roll. Static caster adjustments are still used to change the cars on power / off power steering balance.

Reactive Camber and Front Roll Center:

Reactive camber or camber gain is how much camber is added the front wheels as the suspension compresses. This can be increased or decreased by changing the angle and length of the top arm. Short, angled arm = more. Long, flat arm = less. More reactive camber will typically cause the car to “roll up” on the outer front wheel, transferring more weight in a turn and give more steering up to the point at which the tire is overloaded. This is generally more front grip and weight transfer than wanted on carpet, and as a result most cars run a flatter longer front arm.

Roll Center is the point on which the car will twist laterally or ‘roll’ during cornering. This can be raised or lowered by changing the angle and length of the top arm, with a short angled arm raising is slightly and a long flat arm lowering it. From what I have calculated most modern 1/12 cars meant for carpet have a roll center somewhere around the height of the chassis plate or just below it, but due to the lower arms being rigid and flat the roll center cannot be under the bottom of the tires like it often is on a touring car.
These two are inexorably linked in pan cars. Top arm length can be changed by the top arm mount in or out using shims or a CRC Long Arm kit, but is generally a minor tuning choice. Tuning of roll center with shims is usually a minor tuning choice in a pan car with a rigid bottom arm due to how the car cannot gain extra mechanical advantage on the lower arm as you can in a touring car, while reactive camber can be a significant driver of the car’s performance. In a modern car running on carpet the kit setup is usually perfectly fine.

Front End Alignment:

Static camber is the angle of your front wheels at rest, typically somewhere from 0 to 1.5 degrees on a pan car depending on surface, tire choice, and other factors, but a good starting point is usually somewhere around 0.5 degrees. More camber will typically give more steering, but many racers use static camber to ensure that their tires wear flat even if that means not having exactly equal camber on both sides of the car. This is adjusted by threading in and out the upper turnbuckle or pivot ball.

It is also worth noting that when running on high grip the flex and deformation of your chassis, suspension parts, and front wheels can become significant and cause uneven front tire wear. Some troubleshooting of the right combination of static camber, camber gain, caster, and tire/rim choice may be necessary to ensure even front tire wear.

Toe-In:

The front toe is one of the more easily adjusted aspects of the car and can have a significant effect on the attitude of the car due to it being a quick way to moderately adjust Ackerman without making significant other changes. With nothing else being adjusted, going from zero toe to toe-in will give a car a harder turn-in and will tend to scrub speed with the front end as opposed to using drag brake. This can be necessary when racing in Super Stock or higher power classes and will allow you to drive more aggressively, and can help the car track straighter under power. Toe-out will tend to make the car coast more through corners due to reducing the steering angle of the outer front tire. If a car has too much off-power steering but is otherwise stable, adding toe-out can calm the car but may the car to wander on the straights especially if the front end setup is very soft.

Ackerman:

Ackerman is the difference in steering angle between the two front tires during a turn. It is the result of how during a turn the inside of the car experiences a tighter circle and needs correspondingly more steering angle, but is also an important tuning tool. More Ackerman means having more inside wheel steering angle relative to the outer wheel, less means that the difference in steering angle is smaller.

To add or remove Ackerman, using a servo horn that spaces the links further apart (such as a Kimbrough Small Servo Saver, the outer holes on a Tamiya or Xray servo saver) will have more Ackerman than a servo that puts the links close together (Kimbrough Medium inner holes, Tamiya or Xray inner holes.) The rule of thumb is that a servo that puts the ball studs close together but spaced away from the servo horn will have less Ackerman than one that spaces them far apart and close to the servo horn. Ackerman changes will have the same effect as changing toe with more Ackerman being effectively toeing the wheels out and less toeing them in, but will not affect the straight-line attitude of the car.

Turning Circle / Steering Angle:

In offroad or even touring car you can set up the car to use the full angle of the steering 100% of the time. You will almost certainly not be able to do this in 1/12 scale. It goes without saying that as you turn up your steering angle you will gain steering often to the point of the car being undriveable. The quickest way to set the steering correctly is to set the sub-trim in your radio such that the car tracks straight and the servo horn is straight up and down, then set the endpoints equally such that they don't quite hit the steering bump-stops, then turn down the dual-rate or total throw from there. A typical starting point is somewhere between 45 and 60% of the total steering throw, or a 4-5' turning circle.
Pan Car Rear Pod Tuning:
Modern pan cars are all link cars with a center pivot ball and solid rear axle. This suspension system is required by ROAR rules and has the advantage of being simple, lightweight, and inexpensive compared to other more exotic methods of rear suspension, but it has some complicated movements that can be unintuitive.

Motion of the Rear Pod:

Due to how the rear pod is a solid axle, the only motion the pod itself sees is the main pivot up and down, but due to the main chassis being independently sprung it will feel the lean, dive, and squat of the main chassis as the car is driven. The lateral forces of the main chassis during cornering is transmitted through the main pivot ball and side links, the roll through the side springs and side dampeners, and the squat and dive through the main shock and spring. In addition, the torque of the motor against the pinion gear both during acceleration and braking is significant enough to cause a change in attitude even in low-powered classes. The motor pinion will try to “climb” the spur gear, lifting the center pivot of the car and countering the “squat” of the main chassis weight being transferred backward by the acceleration or the opposite under brakes.

Main Shock:

The adjustment of the main shock of a pan car is one of its more important tuning parameters. Spring, dampening oil, and pod droop are all controlled by the main shock.

Main Spring:

A soft main spring generally means more rear grip and more forgiving off-power, while a stiffer spring can mean more steering especially off-power, but the main spring must also be stiff enough to prevent the chassis from dragging when running on high grip. For most cars the kit spring is a medium weight spring that is a good starting point.

Main Shock Dampening:

The weight of the main shock oil will determine how fast the car will react off-power. 30wt or roughly 300cps shock oil is a good starting point, going up in weight will increase initial off-power turn-in, while going down will generally make initial turn-in softer. Often a heavier shock oil can make the car transition from entry to mid to corner exit smoother, where a car with light fluid may have a more pronounced ‘hook’ in the mid corner.

Side Springs:

The side springs transfer the roll motion of the main chassis to the rear plate via spring tension. Softer side springs give the car more rear grip and can make the car have a smoother steering feel. Stiffer springs promote the cars rotation and give more steering. You can either pre-load side springs or let them float, due to all side springs being progressive beehive shaped springs pre-load makes them effectively harder and will give more steering, but a small amount of pre-load can also make the care more predictable and forgiving. In conditions of extremely high grip, it may be possible to run no side springs at all due to the steering afforded by the tacky running surface and helps prevent traction-roll, likewise in extremely low grip when rear stability is absolutely necessary. Generally 1/12 cars run soft side springs but stiffer ones can be very common in Pro 10, WGT, or WGT-R.

Side Dampener Tubes:

Heavier tube lube will keep a car flatter at corner entry, initiating quicker. It may also make the car square off the corner entry when the grip gets beyond med-high. Going lighter will reduce steering initiation and maybe preferred on higher grip. This parameter is really unique to the driver preference, as some drivers are very fast and consistent with heavily dampened cars while others prefer softer setups.

Droop:

Controlled by the length of the shock, adjusting the rear pod droop is extremely important on high-grip surfaces. Reducing droop prevents the car from transferring weight during cornering and will give more rear stability and prevent traction-roll or problematic lifting of the inside rear tires during cornering, low droop can also give the car slightly more on-power steering. Increasing will allow the car to transfer more weight and dive harder into corners, but by allowing the center of the car to rise you will be more prone to traction roll issues. A typical starting point is 1-2mm of droop from ride height, but 0mm is often used on high grip.

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Old 12-07-2011, 09:56 AM   #37246
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Quote:
Originally Posted by vafactor View Post
It's likely that a major source of your double steering issue is too light of dampening in the side tubes. Most guys run at least 10,000 in the tubes these days (I think the blue cap CRC bottle is about 10,000). A few of the team drivers have been going as stiff as 50,000. I suggest that you try 20,000. Then, an easy way to tell if it's too thick is to run a few laps with the 20,000, pull over quickly and pop off one tube and run a few more laps with just one tube connected. You'll know right away if that simple and quick trackside change made the car better or worse. If the car gets better with just one tube connected, than 20,000 is too thick. If if it gets worse, then 20,000 is not thick enough. Lately 20,000 has been my default tube lube and I go up or down slightly from there depending on track conditions.
vafactor has it right on - this is where to start sorting out your double-steer, right out of a setup guide. solid advice! I bet this will tidy things up in no time.

On thing to consider - you were proposing changing shock fluid, shock spring, side dampening fluid and side spring? Make sure and do these ONE AT A TIME. Otherwise, you have no idea which adjustment had the desired handling change. Start with the dampening fluid as VaFactor recommends and probably about a 90% chance you won't need to touch the other setup changes you proposed.
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Old 12-07-2011, 06:00 PM   #37247
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Default 1/12th scale servo

hey just picked up a 12l4 so i can race at the local track. I used to have one back in the day but anyways. I can not for the life of me remember what servo i had in it so im looking for some cheaper suggestions on a servo for the car. if you have a use something you want to get rid of let me know.
thanks
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Old 12-07-2011, 09:52 PM   #37248
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Originally Posted by travisridenour View Post
hey just picked up a 12l4 so i can race at the local track. I used to have one back in the day but anyways. I can not for the life of me remember what servo i had in it so im looking for some cheaper suggestions on a servo for the car. if you have a use something you want to get rid of let me know.
thanks
travis
At $80 or so the JR 3650 High-Speed Mini is probably the cheapest servo you want to run, I have one and have nothing bad to say about as its been as reliable and consistent as gravity. A cheaper servo such as a Hitec or other brand will tend to have servo centering issues which will make the car wander. It's not a problem in offroad, as I have run Hitec gear in my offroad cars for years to prove I'm not brand-biased, but it will be noticed in the 1/12 scale.
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Old 12-07-2011, 09:57 PM   #37249
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vafactor has it right on - this is where to start sorting out your double-steer, right out of a setup guide. solid advice! I bet this will tidy things up in no time.

On thing to consider - you were proposing changing shock fluid, shock spring, side dampening fluid and side spring? Make sure and do these ONE AT A TIME. Otherwise, you have no idea which adjustment had the desired handling change. Start with the dampening fluid as VaFactor recommends and probably about a 90% chance you won't need to touch the other setup changes you proposed.
On this car, it seems that when I change one thing at a time I wind up instantly changing it back. I'm going up on the dampener fluid to the CRC "white" (the thickest I own, but I can get some diff lube from the Short Bus Truck racers at my track as needed) and softening the side springs in one step, hopefully that will help it out, then I will play with the center shock or the front springs.
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Old 12-08-2011, 12:28 PM   #37250
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Old Timer Question: does anyone know where one can purchase the black rubber tire contact cement we used to mount foams to 1/12th scale rims when using laquer thinner. (fortunately, I still have a Kimbrough 1/12th tire horn )

I'm not a big fan of using slow CA. Thanks.
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Old 12-08-2011, 12:42 PM   #37251
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Originally Posted by Carl Giordano View Post
Old Timer Question: does anyone know where one can purchase the black rubber tire contact cement we used to mount foams to 1/12th scale rims when using laquer thinner. (fortunately, I still have a Kimbrough 1/12th tire horn )

I'm not a big fan of using slow CA. Thanks.
regular contact cement like they sell at home improvement stores (for gluing formica onto plywood) works just fine. The glue line is so thin after the tires are installed that it's not really visible. Normal contact glue will work just fine. I used Hybond 80 glue for years without issue. No need to stress out looking far and wide for black contact glue.
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Old 12-08-2011, 12:51 PM   #37252
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On this car, it seems that when I change one thing at a time I wind up instantly changing it back. I'm going up on the dampener fluid to the CRC "white" (the thickest I own, but I can get some diff lube from the Short Bus Truck racers at my track as needed) and softening the side springs in one step, hopefully that will help it out, then I will play with the center shock or the front springs.
I've found that purple fronts tend to make the car doublesteer. They don't have a ton of bite initially, then when heavily loaded, they tend to dig in. A magenta will have more initial, and more predictable mid corner. Pink fronts will steer even more initially, but not quite as much once loaded in the middle of the corner.

Softening your side springs and adding dampening could actually make your problem worse. The added dampening may be too much for the blue side springs, which would make the car resist centering up after the apex. I would go up in dampening to 20k or even 30k while leaving the white side springs in place. Balancing the side spring rate to the level of dampening is critical for cornerspeed.

With Blue side springs I run no more than 15k in the tubes, White side springs usually 15k to 30k, on the few occasions that I've run Red springs it's been 20k to 50k. With these scenarios the spring and the dampening are evenly matched and the car is very consistent. Less dampening and more spring, the car becomes very "reactive", and tends to double steer. More dampening, less spring, and the car starts to turn-in hard, then gives up mid-corner, then steers hard on exit.
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Old 12-08-2011, 01:04 PM   #37253
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Originally Posted by travisridenour View Post
hey just picked up a 12l4 so i can race at the local track. I used to have one back in the day but anyways. I can not for the life of me remember what servo i had in it so im looking for some cheaper suggestions on a servo for the car. if you have a use something you want to get rid of let me know.
thanks
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I've been using these with great success in my 12th scaler and WGT cars for a few seasons.

http://www3.towerhobbies.com/cgi-bin...&I=LXDTB4&P=ML

I also know a few guys who have been running these, the plastic geared in 12th scale and the metal geared in WGT:

http://www.horizonhobby.com/products...ervo-SPMSA5030


http://www.horizonhobby.com/products...ervo-SPMSA5030

I have one of each on order. Can't wait to try them as they are slightly smaller and lighter than the 9650 with very comparable performance specs.
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Old 12-08-2011, 01:34 PM   #37254
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I've found that purple fronts tend to make the car doublesteer. They don't have a ton of bite initially, then when heavily loaded, they tend to dig in. A magenta will have more initial, and more predictable mid corner. Pink fronts will steer even more initially, but not quite as much once loaded in the middle of the corner.

Softening your side springs and adding dampening could actually make your problem worse. The added dampening may be too much for the blue side springs, which would make the car resist centering up after the apex. I would go up in dampening to 20k or even 30k while leaving the white side springs in place. Balancing the side spring rate to the level of dampening is critical for cornerspeed.

With Blue side springs I run no more than 15k in the tubes, White side springs usually 15k to 30k, on the few occasions that I've run Red springs it's been 20k to 50k. With these scenarios the spring and the dampening are evenly matched and the car is very consistent. Less dampening and more spring, the car becomes very "reactive", and tends to double steer. More dampening, less spring, and the car starts to turn-in hard, then gives up mid-corner, then steers hard on exit.
To my knowledge, the CRC "white" dampener tube fluid is less than 10k, so hopefully it will be fine, thanks for the advice though.
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Old 12-08-2011, 02:01 PM   #37255
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Where can the multiverse diff sanding tool from post 37218 be bought?

Kind regards; Jens
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Old 12-09-2011, 04:49 PM   #37256
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http://www.multiverse.jp/QTEQ/englis...ringtruer.html

You need to contact them (at the bottom of the page)

its 3600JPY and out of stock

Postage is 1500JPY to Australia.

Personally from now on I will be surface grinding the rings flat first then finishing them on some wet and dry. This way they are flat AND parallel. Just doing them on wet and dry may not make them parallel.
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Old 12-09-2011, 09:31 PM   #37257
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When you say double steer what does it actually means? I just recently change my tires the front purple and rear pink, when I changed it it was hooking or.sliding n on a turn. .I don't what my previous tires are because I bought it used with the tires on so I don't know what the shore of the tires are, 1 thing also use the size of tires the previ any advice is appreciated were 42 and and 41 and now it's 44 and 42. any advice is appreciated.
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Old 12-09-2011, 10:12 PM   #37258
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Tire size varies with what you want to do. In a high traction situation like IIC or Snowbirds, they cut the tires very small to minimize sidewall flex and reduce traction rolling. On a lower grip surface, a larger tire will provide more traction but you may need to run a bead of super glue around the wheel on the tire sidewall to reduce flexing. A larger tire will last longer as well if you don't chunk it by hitting too many boards. I've heard "double steer" used to describe a couple of different problems, so I'll let Desert Rat describe exactly what he means.
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Old 12-09-2011, 10:51 PM   #37259
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I tried 30,000 wt fluid in the dampeners and it made the double-steer go away everywhere except for the 90 degree corner at the end of the straight, there I need to roll into the turn and turn the wheel as slowly as I can, which is not in my usual driving style, I usually drive lock-to-lock and when turning into a corner I snap the wheel over and then adjust its final angle with throttle, so I guess I just need to learn to drive it smoother.

When I say double-steer, its when the car initially steers into a corner from straight or in a switch-back and the front end hooks, the back comes out slightly, then it rebounds to a push or snaps the rear back behind the front again, then hooks again in fairly rapid succession. This bleeds massive amounts of energy from the car as it scrubs through the corner. My car does this about twice in a 90 degree corner if I enter at high speed and just snap the wheel over, and it's what I'm trying to get rid of. The car is still very fast but I think it would be devastating if I could get it to settle properly to compensate for my ham-fisted style on the steering wheel.

Next, I am going to try thicker fluid in the center shock, to further slow the transfer of weight, unless that's just the wrong thing to do.
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Old 12-10-2011, 11:53 AM   #37260
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@RBF

Raced my second race with my Rebel12 and did a little better this last race but car seemed to be skaty in the rear end at low speeds.

I was using Jaco magenta ft and pink rear. Pretty small. The first time I raced it I was unaware that the track width had to be adjusted in ft and rear for Jaco's. So I had basically the same set up as first time but fixed track width for jaco's and the car became sorta drivable but had that rear traction problem. Impossible to drive at low speed. Now I'm gonna just use CRC and have track width ft and rear appropriately set.

I'm asking you cause you said you had good experience with the synthetic yellow tires in rear. They have some grey rears at Norcal which I think are just slightly harder than yellow and they have white rear also. I was given like 7 sets of magenta ft CRC so I will just stick with those since they have pretty good steering for probably indoor and out

My question is what might I experience if using the grey/white in the rear. One of the guys in mod here runs totally chunked grey rears and has massive rear bite and lots of steering with magenta ft. I will order some yellow rears to test later but what is your opinion on the grey/white

In general my setup has .020 ft and soft rear springs and medium top with 15000 rear damp side and reactive castor at 5

Just looking for some "drive-able" rear bite and might even run the rear at like 45-46mm to start

When I raced carpet in AZ the whole magenta ft and pink rear was stuck but pink rear is not working for me here so I'm like what's up dude. I also tried grey/white rear in AZ and totally did not work for me like the pink rear and magenta ft so I'm learning about different carpet conditions not to mention the lipo/link cars addition to the sport in relationship to the tires

Thanks David

Kel
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