View Full Version : bump wall, servo lock

2010.06.15, 10:02 PM
I just bought a new readyset MR015 and have an annoying problem :mad:

If I bump a wall with the wheels turned, I get servo lock. The wheels will be stuck, either direction, full turn. I have to manually turn the wheels, 'click', and back to normal.

I race RCP and hitting wall is unavoidable, I searched the threads and is it possible this problem will work itself out? is this true?

Car is new, ran less than 20 minutes, RCP track, the servos are quiet and work good, no centering issues, motor seems strong, stock am radio. BUT I can't make two laps without having to retrive my car and reset the steering!!!

Can anyone help? thank you.

2010.06.15, 10:19 PM
If you feel comfortable, open it up and make sure that there is nothing in the gears, and everything is in the proper place. You can remove and reseat the servo assembly and see if that helps.

2010.06.16, 12:06 AM
EMU, thanks for the reply and advice...

OK, I peeked inside the servo case and saw nothing strange, no dirt, all gears are good, I work the servo and watch the saver move left to right, everything seems smooth.

However one thing does come to mind...

The servo has been noisy since the first time I turned on the car out of the box... almost exactly like an 03 digital steering. Is this normal?

My MR-02 ASF is quiet when I turned the car on, the steering doesn't 'hunt' like an 03. However this 015 is hunting. I could see the gears twitching. Radio batteries are new and car drive ok on the track, no glitch. So I can rule out the radio batteries.

Is this normal or could this be the problem. I thought it was interference from the track but now I'm at home and servo still noisy.

Of course once I turn the steering wheel everything is fine, until I bump the wall while turning, then I get servo lock. FWIW the throttle and motor work fine, forward, reverse no problem.

2010.06.16, 01:10 AM
Are you runnin the stock steering rod? I've had this happen but only after a hard impact. Is thus a box stock rtr?


2010.06.16, 01:52 AM
Kris / byebye,

Yep stock everything, it's straight out the box ready set, even the radio and crystal. Only thing I'm playing with are tires as I dial in the right mix of understeer so I don't flip (90mm HM).

Like you, first time I hit the wall semi hard, the wheels locked. I thought it was a fluke but now any hit at an angle the wheels will full lock.

I don't get it... and the noisy servo while standing still, does yous do it too? (not sure if u have an 015, sorry) Thanks.

2010.06.16, 02:22 AM
The noisy servo usually means the VR pot needs cleaned or replaced. Sometimes even after cleaning or replacing it will still be noisy. I don't know what causes this. Maybe too much play in the gears? As long as the steering doesn't twitch while your turning and accelerating I wouldn't worry. Still a bummer seeing how its new. As for the other problem maybe the servo saver is sticking or it could be the stock tie rod.

2010.06.16, 08:05 AM
I Think you may have too much slop in your servo saver. You should consider an alloy servo saver and tie rod. Is this mr-015 an I-series? I never had much luck with those. The quality in my opnion is not as good as thier predecessor.


2010.06.16, 10:43 AM
Hey Eman, Thanks for the input, yes, it's driveable and handling better everyday as I keep dialing it in. However the servo lock is quite annoying, visually there's nothing wrong, no hang ups, no binding anywhere.

Kris, thanks, it's not an i-series, I'll look into your advice. I was planning on buying tires and an oil shock with my miniz budget, but now I may investigate the servo issue. IMO I don't think it's gears cuz the steering works great, smooth and quiet. it's just noisy standing still and that servo lock :mad: grrrrr.

2010.06.16, 01:15 PM
Drivers, thx again for all the great input. Mmmky, I have a theory :eek:

The kidney shaped hole on my 015 tie rod ends have a kink on the inner shape. Compared to my 02, that inner shape is more rounded, and my PN alloy tie rod, it's a smooth curve!!!

That explains the 'click' I get when I reset the wheels by hand. The kink is catching the knuckle 'arm' at full lock and won't let go...

As a bonus, right hole is kinkier :cool:, so more chance of lock turning right? I'll test that out... Meanwhile if anyone has experienced this, check tie rod ends, how's it look? It doens't have to be a sharp corner, my kink is subtle enougt to catch the knuckle arm with a 'click', enough to servo lock... i think.

2010.06.16, 01:45 PM
make sure nothing is catching on the tie rod cover at full lock. i've had that happen in the past.

2010.06.16, 03:46 PM
make sure nothing is catching on the tie rod cover at full lock. i've had that happen in the past.

arch2b, you are absolutely correct :) the knuckles have 'bump stops' and they caught the tie rod cover at full lock, just as u describe!

My 'kidney hole' diagnosis was wrong :o dang I was so excited too.

I switch to PN alloy knuckles (no bumpstops) and... PROBLEM SOLVED!!! :D

2010.06.16, 08:07 PM
cool, thought i was the only one with that problem:o

2010.06.16, 08:57 PM
thx again, I'm happy now :)

IMO the knuckle 'bump stops' kinda unnecessary, the way they catched the cover, bad design...

FWIW, my friend's MR-02 AM car, servo is also noisy... hmmmm. Oh well, my car drives pretty good, can't complain :rolleyes: