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  1. #1
    RC Enthusiast
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    Tracks straight at low speed...squirrelly at high...

    My merv drives really straight when im driving slow, but when I hit the juice it wants to dart all over the place. GTR shocks, blue summit springs, 70 wt. and minimal preload. RPM knuckles, dirt hawgs on traxxas dish rims...hitec servo...not a whole bunch of play in wheels but I couldnt say there was zero play.

    I was considering a gyro..would that help? Anybody got a link to that little one that fits in blank servo spot?

    Anybody have any ideas on how to fix the darting problem?

  2. #2
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    How is your alignment?

    Zero play is unobtainable with these. Parts are not made with those kinds of tolerances.
    Whatever it is I just said... I could be wrong.

  3. #3
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    Alignment seems ok..looks good to my eye..toe in @ the rear with a touch of negative camber. Fronts are straight with a tiny bit of negative camber. It goes real straight with half throttle. ..if I get on it it wants to dart around. Is it gyro time?

  4. #4
    Marshal Dadx2mj's Avatar
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    I run my MERV with a little toe out up front because I like the quick steering response it gives the truck but a little toe in on the front will help make it more stable at speed.
    BlindMan Racing
    Rusty - MERV - Pede 4x4-Alias
    SPC Lipo Power

  5. #5
    RC Champion
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    I just slapped a Logictech 2100T(same as the Hitec HG-5000) gyro on mine for something to do. Wow, in heading hold mode full throttle runs down the gravel road are no problem. Rate mode takes a bit of driving but still much easier than without the gyro. It does have a weird feel around corners in HH mode that is not present in rate mode. HH also caused problems in reverse, it would just go full lock one way or the other.

    A bit of gyro tuning might help with some oddities I was feeling. The gyro is one I had tuned for the heli it was on before I went flybarless. The only thing I changed was the correction direction, tweaking the gain and rotation rate may help a bit.
    My tranny case is stock :D

  6. #6
    RC Turnbuckle Jr. Jimmie Neutron's Avatar
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    Gyros are weak servo killers... so be sure you have a good one if you go that route.

    I was going to type what Dad did about alignment...
    Whatever it is I just said... I could be wrong.

  7. #7
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    I think I have a set of aluminum knuckles in my future...but might do a gyro just for fun. Anybody know the name of that little black one? Or a link to a good little one? Ive seen that black one on here before. .just can't remember the name.

  8. #8
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    The gyro is kind of cool, I've thought about doing it for a long time since I have four or five of them just sitting around after I switched all my helis over to FBL. Too bad no one makes a brushless, magnetic induction servo the right size for the MERV.

    I don't know if I will keep it on the MERV though, if I was doing nothing but speed runs I could see keeping it, but for general bashing I'm not so sure.
    My tranny case is stock :D

  9. #9
    RC Champion
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    Did some tweaking of the gyro settings tonight and have it working quite well now. I was able to up the gain by 5%, increased the rotation rate. Now it doesn't feel disconnected around corners in HH mode, reverse is still an issue, as soon as the gyro senses any rotation it goes full lock, when you try to correct it, it goes full opposite lock.

    It is pretty amazing how quickly you can accelerate on gravel without spinning out though, very little throttle control required. I'm now wondering how it would do with a pair of Hitec 5083 servos.
    My tranny case is stock :D

  10. #10
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    hey dadx...I went to snug up the caps on my rpm knuckles...do u know what sized hex wrench that takes? My 1.5 is too big...I think it's 1.0...is that right?

  11. #11
    RC Qualifier
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    .050" they really should include a wrench

    IIRC its like 1.27mm

  12. #12
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    Thanks bro!

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