Shift Kit, Bike derailleur problem? (Feel like axle dying) HELP

Discussion in 'Motorized Bicycle General Discussion' started by alienboy366, Sep 16, 2011.

  1. alienboy366

    alienboy366 New Member

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    SO I had my sick bike parts shifter kit on my bike and i'd say have about 250-300 miles on the bike by now. I haven't been to easy on the bike while changing gears and such because i wasn't quite used to it yet so it would jolt a bit after changing gears and such (I do let go of gas and try to gradually accelerate when changing gears). Anyways, now when I go and it seems to be doing this under hard acceleration or strain on drive train. The bike would go, then it would feel like the freewheel of the derailleur would slip then catch again so it would be like the bike is having hiccups. The problem isnt constant, just once in a while. Probably at least 5-10 times a minute of city riding? I'm going to stop riding for now, if anyone knows how to fix then please let me know. If not do you think a bike shop could do a rear wheel overhaul? Let me know please. Thanks
     
  2. decoherence

    decoherence New Member

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    it is the chain trying to jump gears.
    it happens all the time on normal bikes.
    all you need to do is to adjust the derailer to line up with the gears on your shifter.
    it probably just stretched a little so tightening the cable should fix it.
     
  3. KCvale

    KCvale Well-Known Member

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    Sounds like the derailleur to me as well and the easiest to try first.

    But... Your chain could be all beat up and about to break, or your 'early riding' may have even damaged some teeth on one or two of your rear wheel sprockets, most likely gear 2 and/or 3 as typically those are the first 2 gears you use to start with and beat the hardest.

    A powerful 2-stroke motor like say a 66cc with an expansion chamber plays **** on the whole drive train including the Jackshaft parts, but they can really rip a derailleur to pieces in short order, especially a 'budget bike' one.

    I just popped in here to post some info and try to get a little info for my new project to takes some of that 2-stroke pulse-pounding out of the whole drive train on a Jackshafted bike, but I always try to help with a few answers or help from other posts before I ask my own.

    In short, if I can get the design of this right, this is a replacement 'torque dampener' sprocket for the first (left side) sprocket on a Jackshaft kit.

    [​IMG]

    The main object is for that orange rubber like material mellows out the motors power pulses before it even hits the drive train.

    More about this when I post my topic here about it.
     
  4. alienboy366

    alienboy366 New Member

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    O man, thats an amazing idea. WOW. it would help to get the bike started smoother as well hmm. Any idea when this will be available?
     
  5. KCvale

    KCvale Well-Known Member

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    I am still playing with designs for the 'cush' sprocket alienboy.
    The parts are pretty cheap, $13 for the 3 part coupler ($25 delivered) but that does not have a sprocket on it, and the 'cush' material won't have enough give I don't think.

    This all came about because NuVinci won't sell their new Harmony automatic hub to gas bike builders because of the motor pulses so I figured I better find a way to buffer them if I want to try one of these new hubs.

    It is a long design process when you are working with 'spare' money which of course is few are far between.
    If you want to follow the progress you can read this topic.
    KC's Kruisers - Motorized Bike Forum - NuVinci shifter updated?
    It's 3 pages long now.
     
  6. cannonball2

    cannonball2 Active Member

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    I had a similar problem in which the drive skipped in the lower gears. Turned out the the inner drive sprocket on the pedal crank was overunning the chain as it was close to the same size as the lowest gear on the freewheel. The simple solution in my case was to shorten the final drive chain til the derail was pulled foward at about 45 degrees providing more tension, that solved the problem. This is probably a good thing to do anyway when building a shifter bike.
     
  7. KCvale

    KCvale Well-Known Member

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    Indeed good advice cannonball.
    With the chain on the biggest sprocket shoot for the derailleur tensioner to be at or near max forward so there is still plenty of tension on the smaller sprockets.
    AND back off the throttle a tad when shifting.
     

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