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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.

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

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!


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 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 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.
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.

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.

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.

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

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



JFT (Japan Foam Tire)


Enneti (Xceed)

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 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.

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!


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Old 05-10-2011, 05:55 AM   #35881
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I looked at trying to balance a 3.2 with a brushless motor and it would have taken alot of weight. they moved the pod over for a reason. and it all depends on the motor too.

I just switched from brushed to brushless mid season and did not notice any handling problems by not balancing it.

The only thing would be if you had a really low traction surface and there would be more weight transfer to one side and that could cause issues but with the amount of grip on most tracks it will not be a problem.

I also tested weighing the right side of the pod and did not see any change other than more tire wear.

I ran whites just to see. and without weight the tires wore fairly evenly side to side I would say about 1% difference. with the weight the tires wore exactly the same but the wear on both sides were up by about 5%

that was with about almost 17g added
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Old 05-10-2011, 06:39 PM   #35882
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Default Anyone know??

I recently picked this up off ebay and was wondering if anyone knew the company that made this conversion chassis for the 12l series cars.
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Old 05-11-2011, 08:14 AM   #35883
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Default Tyres

Could somebody explain to me why people run the front wheels smaller than the back
I race outdoor
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Old 05-11-2011, 08:39 AM   #35884
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Originally Posted by duggyload View Post
Could somebody explain to me why people run the front wheels smaller than the back
I race outdoor
There are three reasons that I know of:

1. Reduce traction rolling
2. Reduce foam peeling/chunking
3. Tuning aid. The more foam, the more grip. Less foam, reduced grip. So if you need more steering, you can increase the size of your front wheel but at risk of 1 and 2 above. I generally use a 2mm split between rear and front diameters as a starting point.
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Old 05-11-2011, 12:35 PM   #35885
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taken From my 1/12th Bible

"tire split Difference between front and rear tire diameters)
- is pretty useful for tuning steering characteristics.
Larger split - more rear grip, less turn in.
Closer split - more turn in, free rear end.
2 - 3mm of split should be a pretty common number."
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Old 05-14-2011, 04:27 AM   #35886
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Default 3.7 1S battery

has anyone tried using speed power's 6000mah 65C 1S battery?....anyfeed back much appreciated tnx in advance.
TRF - HUDY - Much more - Ride
Proamp Lipo - Speedpassion
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Old 05-14-2011, 07:27 AM   #35887
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I was wondering if a 35 amp hobbywing xerun would work in 1/12 for 13.5 no boost (1cell)? I'm looking for a cheap esc I can put in the 1/12, but also use in my SC truck if I need to. Any input is appreciated.
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Old 05-15-2011, 01:04 AM   #35888
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Default Speedpower 1s 6000mAh 65c Feedback

Originally Posted by TRF4evr View Post
has anyone tried using speed power's 6000mah 65C 1S battery?....anyfeed back much appreciated tnx in advance.
All I can say is, Awesome!!!!!!!! Very nice lipos indeed and you cant beat the price if buying direct off the Speedpower website.
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Old 05-15-2011, 04:54 AM   #35889
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well after 20yrs since i last ran 1, i'm back in the 1:12 game. walked out the store with a 5.1 yesterday along with some trick bits to finish it off. i bought 74T spurs as they were the shortest they had but i've heard/seen mentions to even smaller spurs. there is talk of doin 17.5 during the wk for a more relaxed setup oriented race nite and its gonna require some serious gear. checked nexus, stormer, and ST-no luck. thoughts/info? thx

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Old 05-15-2011, 06:10 AM   #35890
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I'm actually looking for the same info as you, and if I find anything I'll let you know. What else did you get to finish off the 5.1? I'll be running one at MRH as well... Currently looking for a 13.5 setup (Cirtix is what they have, so I think I'm gonna go that way since there is no boost). Just trying to figure out what else may help.

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Last edited by oceanhighz; 05-15-2011 at 06:42 AM.
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Old 05-15-2011, 08:47 AM   #35891
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Guys, check out Jason @ BMI.....he should have you covered. Or PRS (Precision Racing Systems). Both have top-shelf stuff.
R C 3 G R A F I X _ F U S I O N . G R A P H I X _ S E A T T L E - R/C - R A C E R S _ E M E R A L D C I T Y R C . C O M

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Old 05-15-2011, 09:29 AM   #35892
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You really shouldn't need anything smaller than that (I'm assuming 17.5 blinky) a roll out of 4.0 should be ruffly what you need and I can get that with a 76 spur 58 pinion and 1.69 tires (smaller pinion if you run bigger tires). Theirs really no need for a smaller spur.
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Old 05-15-2011, 11:14 AM   #35893
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The new CRC spur gears are great! Lots of diff holes for an even smoother diff. Though with the smaller diff ball you will need to space your axle to compensate. Their gears go down to 72T.

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Old 05-16-2011, 09:14 AM   #35894
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reading the instructions for my 12r5.1 in anticipation of goin home and buildin her 2nite. however i noticed it says the supplied servo saver is an airtronics. well i use futaba. in the picture it doesnt look like a SS with inserts-just a standard kimbrough-esque unit. so does that mean i have to go to the hobby store and pick up a futaba servo saver? kinda dumb move there if thats the case.

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Old 05-16-2011, 09:43 AM   #35895
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Yep. They designed the car with servo mount spacing for a Futaba, then include the horn for an Airtronics..
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