RC Car - My Car Spins While Braking

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My Car Spins While Braking

Comments: I just put together my HPI RS4 Pro 2 a few days ago... it rides pretty good.. I'm still working out a good camber and some other things... but... I have a problem which I do not know where to start troubleshooting. If I speed up to full speed (Trinity 14 turn motor and a 2 speed transmission) then pull back with full brakes, the car slows down to about half speed perfectly straight... then... skids to the left and comes to rest pointing 180 degrees from where it was going. I'm thinking something in the diff might be screwy? Any ideas would be useful!

Response: It is really hard to solve a problem when I don't have the car in front of me. First, check to see if the "Tweak" of your car is set right. This means that there is equal weight on all 4 tires when the car is level. The first thing you need to check is that the chassis is flat and not twisted. You can usually do this with a straight edge or a flat surface. If your chassis is twisted you must straighten it or replace it. Next, you want to ensure that the pressure applied by the shocks to the suspension is equal from left to right. You should have a "Tweak Station" such as the one available from MIP to do this properly. You can use the spring collars to make fine adjustments ensuring that the left to right pressure is equal.

You should also make sure the droop is set equally. To check this, lift up the front end of your car using the sharp end of a razor blade in the center of the front of the chassis. Slowly lower the car to the ground and both tires should touch the ground at the same time. If not, adjust the droop screws so that they do. Repeat this again for the rear of the car. Now your droop is set and the balance of the car is better.

Next, make sure that all of the axles are spinning freely. If one of the wheels are binding more than the others, it may brake before the others causing the car to turn while under heavy braking. All 4 wheels should spin freely at all times.

Let's take off a few tenths per lap,

"PRO"
Pro Racer Secrets