My ATX's steering is a bit restricted at full throttle. When you try to steer the car, at around 3/4 of it's top speed, it doesn't so much steer as drift in a huge turning circle. Is this a sign that my steering servo is too weak for the job? (I've got a Multiplex Profi at the moment)

The steering servo could be to weak. It is hard to tell without the specs.
Another possibility is that the servo saver has backed off and not letting the tires stay in position.
You should check the servo saver before you replace the servo.



rolland

It could be that you have a weak steering servo, its not a bad idea to upgrade the stock one anyway. I have to say though, it sounds like you are describing the effects of centrifugal force. The faster your car goes, the more it just wants to go in a straight line. There is nothing wrong with your car, its just the effects become more apparrent at higher speeds and on a loose surface. A stronger servo will fight understeer a little better though so thats where I would start.

try slightly lifting the throttle just before u turn, as soon as u have started to turn, gently get back on the throttle and try to find a balancing point where it drifts around nicely without losing too much speed, too much throttle and it will snap back to understeer. its a very fine line, and u cant get back on the throttle too early with 4wd, or u are back to understeer again. much the same as driving a 1:1, its down to the weight transfer of the supension for setting up into a corner.

i had the same issue with my rally setup, i made up a rear anti roll bar to help stop the front inside wheel lifting when i got back on the power, it helped quite a lot - i think there are some pics in my signature link. i also softened my suspension quite a lot to allow more weight transfer so it was more obvious what was happening and when, and what caused what to happen to the handling etc, whilst i was driving it... it helped me to set it up to my driving style - it ended up a lot softer than i thought it would.

an uprated servo and a tight servo saver will help it all regardless of setup tho

hope that helps

The only specs that I can find on the Multiplex servo that you are using are around 60oz of torque at 6 volts. If this is what the specs are for your Profi then you definetly need to upgrade the servo. Something like a Hitec 645 would be my recomendation.



rolland

Thanks for the advice guys.