revo steering problems
 

i've got a revo platinum that for whatever reason, tracks straight with no trim, and within the same tank needs 6 clicks of right trim to track straight. again, within the same tank, i'll have to go back to 0 trim to get it going straight again. any ideas?

i'm running two hitec hs-7985mg's, ofna 1200mah nimh, and airtronics m11 w/ 4ch rx. mechanically, everything "appears" to be fine. i had a wild thought, is it possible the hitecs are pulling more amps from the rx battery than it can handle causing my servos to have a brain-fart momentarily? by the way, everything is newish, with at most 20 tanks on this setup.

any help is appreciated. thanks, chris

check your servo saver it might be stripped at the little button that adapts to the servo under the servo saver

Make sure the long srew that holds the servo saver in place is aligned and everything is smooth. Make sure both servo horns are intact and neither is stripped.
If all is good......Start with the tierod ends both front and rear, then the pivot balls........Sometimes the cup that holds the pivot balls snug will back out a little and you will get some "slop" that could cause this.

How much torque does each servo have?. You may only need one. Dual steering servos can cause alot of problems unless they are perfectly matched. They are probably binding and fighting each other. :weird: Everyone who races a Revo uses one strong servo instead of two. :nod:

Beyond something obvious you could see wrong with your steering rack, a very loose servo saver, or some serious binding in your pivot balls, there can only be 2 causes for what you describe, stripped servo gears or stripped splines in the servo horn. If you are using the 2 stock servos I doubt you have stripped servo gears as it would require both servos to have the same gears stripped in the same places for it act that way, but since they are both working on the same rack it's possible they both have gears stripped in the same places. Give the entire rack assembly a good looking over for cracked or broken/worn out parts, make sure your saver nut has not backed off, and make sure your pivot balls are all free. If you don't find the culprit pull the servo horns and see if the horn splines or output shaft splines on your servos are stripped, then check the servos for stripped gears. If you don't find the problem after all that, I'd say make sure your radio rig is not acting up.

As has already been mentioned, you would be better off with a single high torque (at least 200 oz/in) metal geared analog servo for steering in your revo.

thanks guys. lots of things to check. I'll let you know my findings. I'm pretty happy with the dual servo setup (when it was working) because I liked the sub .15s transit speed at that combined torque 344 oz-in.