Results 1 to 12 of 12
  1. #1
    RC Racer
    Join Date
    Dec 2010
    Posts
    147

    steering servos for the fiesta ?

    Ive gone through two servos is there any other kind of servo that would stop breaking

  2. #2
    RC Enthusiast
    Join Date
    Jan 2011
    Location
    Concord, CA
    Posts
    36
    This is weird... One the guys that I see at the LHS carpet track had the same thing happen to him on his rally in 1 month. Ive been beating this KB for 100+ packs the last 3 months and haven't had any servo issues yet. *Knocks on Wood*.
    You can probably get a new spektrun servo? Not sure if you also have to get the receiver and controller as well...
    Slash 4x4 & KB Rally

  3. #3
    RC Qualifier
    Join Date
    Jan 2011
    Location
    TX
    Posts
    578
    Quote Originally Posted by marshallrc View Post
    Ive gone through two servos is there any other kind of servo that would stop breaking
    Check everything for binding. I had a knuckle bind on me and fried a servo.
    Rally SV2/4600 and fully loaded

  4. #4
    RC Champion
    Join Date
    Jun 2003
    Location
    We-Go, Chicago, IL
    Posts
    2,674
    I just lost the servo in my Fiesta tonight and it took the ESC with it. I've already called Traxxas about the ESC but didn't discover the bad servo until after I got home for work and they closed for the weekend. I was hoping the servo was ok, I was going to stuff the Velineon system from the thus far abandoned Bandit drag/land speed project in it.
    Aw, Biscuits!

  5. #5
    RC Champion
    Join Date
    Dec 2010
    Location
    United K
    Posts
    1,042
    I think there's the hitec hs81mg, it has metal gears but it's not waterproof.

  6. #6
    RC Qualifier
    Join Date
    Jan 2011
    Location
    Bay Area, CA
    Posts
    438
    Signs of a fried servo?

    Car turns on normally, the throttle runs the motor fine... But as soon as the servo tries to turn or center, the the esc light goes dim and the motor stops. There's a tiny hum coming from the servo itself. The on/off button on the ESC won't turn the setup off, so I have to unplug the battery to clear the lights. The esc and receiver lights blinking very rapidly red/green when this first went down.

    This one's just a couple weeks old and not even been run very hard. :/
    Last edited by prototyp; 03-12-2011 at 09:54 PM.

  7. #7
    RC Qualifier
    Join Date
    Jan 2011
    Location
    Bay Area, CA
    Posts
    438
    Tore everything down... yup, servo. All's well with my old (internally messed-up but not fried) servo plugged in.

    Yay radio/esc/etc isn't dead. Boo, time for servo number 3. These things are VEEEEERRRRRY fragile eh.

  8. #8
    RC Enthusiast
    Join Date
    Mar 2011
    Posts
    33
    Quote Originally Posted by prototyp View Post
    Boo, time for servo number 3. These things are VEEEEERRRRRY fragile eh.
    my son and I have each had mini-revos for going on 2 years how, and we also each got a rally back in november to race at our local carpet track, and neither of us have ever fried or torn up a servo after hundreds of battery packs.

    servos generally on tear up in these cars for one of three reasons, but most are user error: if you crash into something with the wheels turned, it can blow the gears; if you land jumps with the wheels cocked, turning, it can also strip gears; if you install aftermarket pillowballs and have them too tight, it puts extra strain on the servo and can burn up the motor.

    for this size of car the stock servo is actually very stout, and it has been our experience that the people that have servo problems are usually to blame themselves.

    but the main problem I see is that people do not turn down the exponential or throw on their controllers, this is covered in your user manual, and I don't know why. because racers do it routinely. with the steering set at maximum it requires the servo to work extra hard, and unless you are running very slowly in a very confined area there is no reason to need the car's full steering potential. on our cars we probably have the steering set to maybe 50 or 60%, and not only do the cars drive better because they don't spin out as easily, but it's also easier on the servos.

  9. #9
    RC Qualifier
    Join Date
    Jan 2011
    Location
    Bay Area, CA
    Posts
    438
    Servo #1 has internal position-pot issues... the pot's out of alignment and apparently dislodged enough so the little tab on the pot's shaft doesn't engage with the slot inside the output gear. Every turning event would throw the pot and output gear further out of sync... Seems to be an assembly problem as the inside of the output gear was distorted (overtightening? too long a screw?). Was a little frustrating debugging that issue.

    Servo #2 pooped while doing some drifting out on the street. The extremes of turning angle in my RPM hubs is tighter than the rest of the travel; I wouldn't call it binding but perhaps my servo disagrees.

  10. #10
    RC Enthusiast
    Join Date
    Mar 2011
    Posts
    33
    Quote Originally Posted by prototyp View Post
    Servo #2 pooped while doing some drifting out on the street. The extremes of turning angle in my RPM hubs is tighter than the rest of the travel; I wouldn't call it binding but perhaps my servo disagrees.
    when assembling the RPM hubs, you need to make sure the pillowballs do not bind. they should be able to wiggle around in the hubs quite freely, and move all around the full rotation without binding. if they don't, then you have tightened the screws too tight. and it will kill a servo if you have them too tight.

  11. #11
    RC Qualifier
    Join Date
    Jan 2011
    Location
    Bay Area, CA
    Posts
    438
    The RPMs are set up fine. In fact, they've worn down a bit and are in need of tightening again. The tightness in the steering rigging is at the outer extremes, outside the servo's normal swing limits.

    Anyway, tore down the 'fried' servo. Gears are all 100% fine, and the motor spins up if I crank the position-pot shaft. But it 'crashes' when trying to wiggle just a little bit off center. Also a definite binding when spinning the little gear by hand. Something in there is not happy.

    Anyone gotten the wire/motor end of one of these servos apart? Seems to be very tightly fitted...


  12. #12
    RC poster
    Join Date
    Jan 2011
    Posts
    13
    Set the end points for the steering. Check the transmitter's manual for the 'how to'.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •