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Old 05-04-2010, 10:31 AM   #1
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Default TC4 Issue

I have a TC4 with a Losi Excelorin 7500kv system in it. It always pulls to one side off the line and spins like mad to the left but not to the right. Can anyone tell my why??? Still, once it gets going, it's fast as hell!
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Old 05-04-2010, 10:49 AM   #2
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Good day!

How is your side to side ballance and are the diffs in good shape? The TC4's do have a pull under power, it has to do with the fact that it is a drivshaft car. I ran on last year as my first car an had a blast. Also is your allinement corect?
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Old 05-04-2010, 11:20 AM   #3
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It's called torque steer. It is a vary common problem amongst shaft cars.
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Old 05-05-2010, 08:12 AM   #4
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It's got a solid front axle, so I was thinking about loosening up the rear diff to make it "pull" more than "push" hoping that would eliminate the problem. I have heard about the shaft drive issue but didn't realize that it could be so bad. I'm gonna take the whole thing apart and clean and re-align everything, but with this much power I have a feeling that it's not gonna solve the problem, maybe just "lessen" it.
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Old 05-05-2010, 08:44 AM   #5
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and you should see it when you have a "supercharger" profile on your esc.... my car handles just fine but now with some of these new profiles out when the motor winds out on the straight it give the car a bobble.... it all good if you ready for it
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Old 05-05-2010, 08:45 AM   #6
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Default Hard hit

If you clamp the throttle from a dead stop with a high powered motor, the torque reaction will load up the right side of the car while unloading the left side. More traction on the right than on the left will make the car turn left.

Two choices: anticipate the torque steer and make a steering correction to the right. This may take some practice to get right. Or squeeeeeeze the throttle off the line to minimize the hard hit of the torque.
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Old 05-05-2010, 08:48 AM   #7
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Quote:
Originally Posted by jhberger View Post
If you clamp the throttle from a dead stop with a high powered motor, the torque reaction will load up the right side of the car while unloading the left side. More traction on the right than on the left will make the car turn left.

Two choices: anticipate the torque steer and make a steering correction to the right. This may take some practice to get right. Or squeeeeeeze the throttle off the line to minimize the hard hit of the torque.
I just anticipate... kinda easier than all the crap you go through with losening things....
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Old 05-05-2010, 09:22 AM   #8
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all good advice. thank you all! another thing I could do is reprogram the trottle curve on the esc and have it take off a bit slower. but the last time I tried that the esc seems to be a bit "off". that could be a problem with the program itself I think.
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Old 05-05-2010, 10:32 AM   #9
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you could put some toe-in on the front to make the car track stright.
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Old 05-05-2010, 10:58 AM   #10
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toe in??? I thought toe OUT in the front for straight tracking.
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Old 05-05-2010, 11:17 AM   #11
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Quote:
Originally Posted by Foxxrocket View Post
you could put some toe-in on the front to make the car track stright.
mine tracks just fine... and I kinda think yours does too.......It is just what was mentioned before.... with a shaft drive car there is torque steer... it just happens... honestly I wouldn't change your car... it is something you either have to live with or change to a belt drive car....
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Old 05-05-2010, 11:25 AM   #12
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check your droop screws. everyone blames it on torque steer. if your car pulls to one side under power, but is straight if it coasts then make sure your droop is set properly on all 4 corners.
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Old 05-05-2010, 01:08 PM   #13
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Quote:
Originally Posted by therizzle View Post
toe in??? I thought toe OUT in the front for straight tracking.
Toe-in forces the car's slip angle inwards, so the front of both left, and right tires are working against each other. And because the car's tires want to turn in on each other, this makes the car track stright. But this also makes the car want to push comming out of the corner. Normal car setups have toe-out in front and toe-in at the rear.

It could also be the car's steering linkage. I've noticed when I also had this problem, that there was a little play between the steering bellcranks and the steering bellcrank posts. I placed .010" shims under the steering bellcranks to remove some of that play.
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Old 05-06-2010, 06:34 PM   #14
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Quote:
Originally Posted by Double D Donuts View Post
check your droop screws. everyone blames it on torque steer. if your car pulls to one side under power, but is straight if it coasts then make sure your droop is set properly on all 4 corners.
I'm going to go with checking droop also. I have a tc4 used for speed runs only and it drives straight. Now if the droop get off alittle then it will pull to one side.
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Old 05-07-2010, 02:03 AM   #15
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make sure your shocks are of equal length and rebound too

As others have said though, torque steer might be what is causing it though, that motor sounds pretty quick.
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