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Old 10-08-2013, 04:53 PM   #16
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..I experience this with a small 1/18th on-road racer I built. I put a 12t brushless and lipo power, etc... for a car that is feather weight it too spins out at full throttle or anytime I get on the throttle 100%.

I believe this is a result of the tires ballooning ...which is the result of the tire type and the power output from your motor.

What i've found is that if you ease the power on you can avoid your car from spinning out ..dont' jam on the power. Also if you can try a lower profile tire or foam tires ...something that won't balloon that too may help.

Or dare I say, go to a slower motor (i know, that is an unpopular choice).
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Old 10-08-2013, 05:11 PM   #17
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All wrong here !!!!!! You need to Check/change your wheel Bearings....
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Old 10-08-2013, 05:19 PM   #18
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All wrong here !!!!!! You need to Check/change your wheel Bearings....
Why could it not be one of the other things mentioned?
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Old 10-08-2013, 05:22 PM   #19
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The OP mentioned that he is running a TC4 which comes with 3 degrees of rear toe (at least the new Club Racer kits do).

Assuming that the car is mechanically sound (no broken/damaged parts)...

I would agree with other posts that the tires could be ballooning. Another cause could be poorly glued tires pulling away from the wheels, which would have the same effect as the tires ballooning.

Check all 4 tires to make sure they are still secured to the wheels. If you bought pre-mount tires and plastic chrome plated wheels, you may have problems with the chrome separating from the wheels and/or tires. If you are running a high powered motor, it can cause the tires to pull away from the wheels regardless of the type of wheel.

The reason for the spinning would be one (or more) of the tires rubbing the body. This can act like a hand brake at high speed. Check for wheel marks on the body. A loose tire can will also be very unbalance and will cause that end of the car to hop (and lose traction).

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Speaking of ballooning tires...you can try mounting your body a little higher up to see if this resolves the problem. Replacing your current tires may not be an option, so you may be "stuck" with non-belted tires. Other than running without a body (which I DO NOT recommend), you could raise your body up a little bit and see if the problem goes away. This could also help you isolate the cause as a tire rub or even a part of the body rubbing the ground.

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It may be possible at higher speeds the rear of the chassis is being compressed and will be much closer to the track surface. Check the underside of the chassis to see if you have a lot of scratches at the back. This could be an indication that your chassis is bottoming out.

I would recommend that you have at least 5mm ride height (or more) when running outside on an unprepped surface. This will help make sure that your chassis will clear any debris and/or uneven surfaces like cracks in asphalt.

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One last bit of advice, if possible have a friend or fellow racer stand near where your car is having an issue (from a safe viewing position). They might be able to hear or see something than may help isolate the issue you are having.
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Old 10-08-2013, 05:39 PM   #20
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Also, your droop/setup got to be on point too.... No way a 4600kv or 7700kv is too much for a tc4 !!!! Watchout for these rubber sealed Bearings !!! Best to remove the seals !!!
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Old 10-08-2013, 05:58 PM   #21
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Because the OP would have noticed unglued Tires, ballooning Tires, etc.... It seems that problem is not visible, which excludes the Tires.. If you Work your way from outside in then the next thing to Check are the wheel Bearings..... It happened to me alot when I ran the rubber sealed Bearings on my axles. Teflon sealed Bearings don't do this alot, but do need to be changed eventually. The rubber seals expand with friction/speed and brake the wheel....
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Why could it not be one of the other things mentioned?
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Old 10-08-2013, 06:10 PM   #22
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Because the OP would have noticed unglued Tires, ballooning Tires, etc.... It seems that problem is not visible, which excludes the Tires.. If you Work your way from outside in then the next thing to Check are the wheel Bearings..... It happened to me alot when I ran the rubber sealed Bearings on my axles. Teflon sealed Bearings don't do this alot, but do need to be changed eventually. The rubber seals expand with friction/speed and brake the wheel....
Sadly i am with Bertrand, i would be looking at bearings and rebuilding the rear diff, if it is a ball diff, i would be making sure the thing is smooth and loose, sounds a lot like my 12th car when i add 1/4 turn too much diff action. On power it does pirouettes. Also look for binding of the suspension on one corner, that can make the car do crazy things also.
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Old 10-08-2013, 06:17 PM   #23
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I would have to disagree about a newer racer not noticing a defect in a tire. I race with newer racers every week and see them miss some of the most basic issues Including poorly glued tires. Mainly it is due to lack of knowledge and experience.

When I was a new racer I just assumed you glued up tires (or bought pre-mounts) and forgot about them. Since the tires are THE ONLY THING touching the ground., it is always a good idea to check them first if you are having a strange issue with your car.

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It is best to check (or re-check) all of the simple things first before replacing parts (such as bearings).
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Old 10-08-2013, 07:12 PM   #24
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Indy, you did not make ”tech elite” yet , you're still a new racer !!!! Lol !!!
All I am saying here is you can see the Tires, and not the Bearings, diffs, etc.....,and I trust the new racers to notice that too !!! Don't put newbies down please !!! You're still One of them !!!
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Old 10-08-2013, 07:41 PM   #25
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Indy, you did not make ”tech elite” yet , you're still a new racer !!!! Lol !!!
All I am saying here is you can see the Tires, and not the Bearings, diffs, etc.....,and I trust the new racers to notice that too !!! Don't put newbies down please !!! You're still One of them !!!
There is too much superiority in the RC hobby its crazy.

Post count has no definable correlation to how experienced you are.
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Old 10-08-2013, 07:57 PM   #26
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It's unbelievable how some don't have a sense of humor ! Newbie status is a relative term .....
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Old 10-08-2013, 08:16 PM   #27
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It's unbelievable how some don't have a sense of humor ! Newbie status is a relative term .....
well I didn't get the implied humor in your post. my mistake.
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Old 10-08-2013, 08:25 PM   #28
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No problem..... I hope folks understand that everything needs to be checked before pushing a Rc Car to the limit...
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Old 10-10-2013, 09:13 AM   #29
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Tore car apart last night and checked everything. Bearings all good, Body not rubbing and the tires balloon a little bit. The ball diff is set pretty good. And if i start out slow maybe just to get it rolling and punch it, it goes straight then spins out after about 75 feet. I also checked the glue on all my tires and they are all solid and it tact.
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Old 10-10-2013, 03:09 PM   #30
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If the spinning out only happens when the car is 75ft away, it could be a radio related issue (weak signal). Let us know what type of radio equipment you are using.

If you are using AM or FM, you will want to make sure the receiver antennae is inside an antennae tube and is located outside of the body. Also make sure to have your transmitter antennae extended to the maximum length. This will help reception at long distances.

If you are using Spektrum or 2.4ghz equipment, make sure you don't have any visible damage on the transmitter/receiver antennaes.
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