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Old 03-02-2025 | 10:36 AM
  #50356  
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We have plenty of noob friendly classes. Hopefully motor tech stays put, where it is, for a while.

17.5 12th scale really isn't too bad on bigger tracks.

WGTR is nice and slow. The only major issue is some cars are brilliant, some are duds. Can be a bit frustrating. But still a great feeder class to 12th scale.


Nascar and tt02 are cheap easy fun. If your track can run them.
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Old 03-05-2025 | 07:02 AM
  #50357  
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The 21.5 USGT motor should not be getting hot in a 12th scale. I think most people over gear them. I ran 59/62 (SJT rubber) last time out on a 90x48 track and the motor was about 125 after each run. Going up to 1:1 ratio as is normally suggested as the "gold standard" didn't go any faster and only amplified any bad lines by taking away bottom end torque.

13.5 100% benefits from a fan. 17.5 as well, though I haven't run it in quite some time. If the motor isn't getting above 150 a fan won't do much. 13.5 shine on the ragged edge of melting down so a fan is great.
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Old 03-05-2025 | 07:11 AM
  #50358  
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My high horse about motors and overall speed...

Corner speed is too high and motors are all torque with giant gears giving us no feel to the throttle. Going higher wind does slow the cars, but they would be much more engaging to drive with a motor that still has good rpm but much less torque.
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Old 03-05-2025 | 07:17 AM
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The problem is, that does seem to be inherently slower. Torquey motors don't spin as fast, and generate less heat. I also can safely say that, at least for 1/10 carpet off road, a torquey motor will always be faster as newer carpet tracks have incredibly short run ups to jumps and between corners. You need the low end power to be fast in those. That's why the newer Tekin SpecR2 motors are much slower and more powerful. That all being said, I miss by old SpecR motor that had no torque and spun to the moon. I had one in my wheeler and it drove like a mod car. So fun!

17.5 is pretty much full beans everywhere, but a 13.5 car with a spinny motor would be so fun.
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Old 03-05-2025 | 09:21 AM
  #50360  
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Originally Posted by gubbs3
My high horse about motors and overall speed...

Corner speed is too high and motors are all torque with giant gears giving us no feel to the throttle. Going higher wind does slow the cars, but they would be much more engaging to drive with a motor that still has good rpm but much less torque.
Remember the old pink can (brushed era) that was way lower in RPM but WAAAY higher in torque. SO much more fun to drive with them.

Torque is so much fun.
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Old 03-05-2025 | 10:56 AM
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Not quite. I started around the Green Machine/Paradox days. But back then, anything that was more powerful was better. Doesn't translate to today where you can simply bolt in ridiculous power at will.

Maybe the Nascar fans out there like racing where you just hold the throttle down. That's fine. Go oval racing if that's what you want.
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Old 03-11-2025 | 11:01 PM
  #50362  
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It an amazing in formation
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Old 03-16-2025 | 07:37 PM
  #50363  
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After a couple minutes running my main, my car falls off on lap times. Goes from mid 9 second laps to only being able to do low 10s. The top guys in the main are able to do mid 9 second laps the whole race consistently. Could this be motor/battery problem? Tire prep? Chassis issue?
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Old 03-16-2025 | 09:03 PM
  #50364  
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I think it’s important to first figure out whether your setup is falling off, your power package is falling off, or if you are falling off(fatigue is a real thing in an 8 minute main). Some things to look at:

- Most importantly: Are you driving clean heats? Because if not… then most of the following doesn’t matter nearly as much.
- Have you done any testing to see how tire prep affects performance at that falloff point? Does it matter?
- Have you done any testing to see how chassis changes affect things long term? Does anything help? (I feel this is most unlikely as chassis setup doesn’t change much in a heat aside from ride height due to tire wear.)
- Are your motor temps okay? Rollout too high/low and causing fade?
- Are you checking battery voltages and IR to see if you’re dumping more aggressively than is typical?


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Old 03-17-2025 | 04:29 AM
  #50365  
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Originally Posted by mtbwrench
I think it’s important to first figure out whether your setup is falling off, your power package is falling off, or if you are falling off(fatigue is a real thing in an 8 minute main). Some things to look at:

- Most importantly: Are you driving clean heats? Because if not… then most of the following doesn’t matter nearly as much.
- Have you done any testing to see how tire prep affects performance at that falloff point? Does it matter?
- Have you done any testing to see how chassis changes affect things long term? Does anything help? (I feel this is most unlikely as chassis setup doesn’t change much in a heat aside from ride height due to tire wear.)
- Are your motor temps okay? Rollout too high/low and causing fade?
- Are you checking battery voltages and IR to see if you’re dumping more aggressively than is typical?

-I usually am in the bottom of the A sort and main at my local track and don’t have a problem with getting into another driver’s car.

-What would be a way to test tire prep? Should I try to let the sauce soak longer?

-Motor seems to come off hot but still cool enough to touch it with your finger for a couple seconds. I should monitor motor temps more carefully with a temp gun.

-I recently purchased a new battery, an EAM stock spec one. IR on it is 1.1-1.3 range. How would I check if the battery is dumping?


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Old 03-17-2025 | 05:14 AM
  #50366  
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Originally Posted by blwaz23
.

-I recently purchased a new battery, an EAM stock spec one. IR on it is 1.1-1.3 range. How would I check if the battery is dumping?
Track voltage of battery when it comes off track and how many MaH you're having to pour back into the battery when charging.
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Old 03-17-2025 | 06:07 AM
  #50367  
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Originally Posted by blwaz23
After a couple minutes running my main, my car falls off on lap times. Goes from mid 9 second laps to only being able to do low 10s. The top guys in the main are able to do mid 9 second laps the whole race consistently. Could this be motor/battery problem? Tire prep? Chassis issue?
What class you running? If 17.5, .4-.6 fall off is pretty normal if not using a fan.
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Old 03-17-2025 | 08:59 AM
  #50368  
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Originally Posted by chensleyrc1
What class you running? If 17.5, .4-.6 fall off is pretty normal if not using a fan.
13.5
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Old 03-17-2025 | 09:20 AM
  #50369  
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Hello Legends!
We just put down 22x60 of Black carpet adjacent to a popular indoor off road carpet track here in Portland, OR.
There is interest growing as more and more of us show up with 1/12 21.5 Foam LM cars. The interest is coming from off roaders so I'm wondering how to best guide someone to the class.
Any tips on how to get seasoned off roaders into this class without the sticker shock of an Awesomatix or wild esc's?
It's been a pleasure to wheel a pan car again.
-Tommy
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Old 03-17-2025 | 09:48 AM
  #50370  
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GT12 rubber tire would be a fantastic starter class. Cheap spec motor, don't need a fancy servo or ESC, and they're easier to tune and drive thanks to the tire setup. You can also be competitive with older chassis in that class. A guy in my local club runs an RC12L and wipes everyone with it. I built up a car, fully new everything, for around $600, and I feel that's pretty approachable when you consider just the kit for most 2wd buggies is close to $400.

GT12 rubber tire also eliminated the need for anyone to use a tire lathe if you go with something like the Gravity tires.

As a next step, 17.5 stock seems obvious. You're introducing open motor and foam tire game with that though(aka - increased cost of entry and money making some folks more competitive than others).
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