Originally Posted by Master7Zero
Hello everyone, first post here. Pretty much me and my brother bought an hpi evo 3, did the break in , car performs great motor wise. But since we got it, it never can drive straight. It will go straight for like a couple feet then go either left or right, mostly left. No matter what we do we can't figure out what it is. We even changed the servo to something with metal internals and still the same.
Have you tried adjusting the steering TRIM knob on the Tx (radio) to see if the car comes back to center?
bring it back to center.
If it takes TOO much steering trim you can set the trim knob back to center and gradually in SMALL increments adjust the servo link until it drives straight.
However, if you have excessive steering slop the car may still wander.
Check for steering slop = all electrics ON - this tightens up everything sort of - grasp one front tire at 3 & 9 o'clock and work gently right and left to see how loose the steering assembly parts are.
Does your Evo have FIXED/non-adjustable steering links?
If you have FIXED/NON-adjustable steering links and excessive slop you may consider changing over to adjustable steering links and ball cups.
If you have adjustable steering links - check for slop the same as above.
These may have to be tightened up some. Run through the posts here for some pointers on how to accomplish that. HPI Sprint 2 Mods - Making a silk purse from a sow's ear.
Another issue could be the OEM servo. Mine was crap right out of the box.
Upgrading to a digital servo and installing a capacitor (digital servos are energy hogs - the cap acts like a mini battery and stores energy to eliminate servo glitches) on my Sprint 2 Sport (electric) got rid of the wandering to the left when all else failed.
I suggest going with just the capacitor first. I use the Associated LRP BEC Stabilizing Capacitor part #LRP80135 = cheap @ $10. Besides, if you upgrade to a digital servo you'll need one anyway.