Shift kit and deraileur gears

Discussion in 'Motorized Bicycle General Discussion' started by Maxvision, Jan 15, 2010.

  1. Maxvision

    Maxvision New Member

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    Wow, took a closer look at my 7 speed hub today. The gears are really messed UP. Teeth bent, teeth broken. I have a shift kit and always back off the throttle to shift and give the deraileur plenty of time to shift gears but MAN...they are MESSED UP.

    I'm guessing maybe, since I have a stretch frame and with the extra weight of the longer chain, the deraileur springs aren't quite strong enough to keep the chain tight like it should be...it seems to skip teeth from time to time....I don't know...Anyone else having a similar problem?
     
  2. Cannonfish

    Cannonfish New Member

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    How long have you been riding on that cassette and chain? I don't know how much extra wear the shift kit places on those components, but I used to tear up cassettes and chains on my human-powered (no engine) mountain bike every 500 miles or so. Just from grit and crap in the chain, I figured.

    How often do you clean and lube your chain and sprockets?

    I'm definitely curious to hear more about this, since I'm still in the middle of a shift-kit install on my bike right now.
     
  3. Ghost0

    Ghost0 New Member

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    I have been running mine for well over a year and haven't had any damage. The only time mine ever was damaged was when I let someone I didn't know ride the bike. Don't know what they did but it came back missing some teeth.

    I think your assessment on the extended chain may be accurate. I would suggest removing a few links from your chain in an attempt to increase the tension on the chain. I have mine set so that when I am in the largest gear (1st), my derailleur arm is pointing forward at about a 45 degree angle. The way I see it you aren't in 1st very much and as you hit the taller gears it will straighten out to a more normal stance but will still have added tension over what you would have had without the shortened chain.
     
  4. Maxvision

    Maxvision New Member

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    Oh, I've driven maybe 150 miles since I put on the shift kit. I keep the chain well lubed and dirt hasn't really accumulated on the gears. The problem is not the gears wearing like normal wear and tear. The teeth are actually twisting so they look more like turbine fans than gears.

    The chain on a stretch cruiser is quite long and it bounces alot when I ride. I'm guessing the chain is traveling through the deraileur faster than the spring is able to return tension when it bounces and that's what's causing it to skip teeth. I think I'm going to try to find a way to beef up the springs to accomodate the extra weight of the chain and see if that helps. Or...maybe just dump the whole deraileur and get a 3 speed hub even though I've heard of them turning to mush on a motorized bike.

    Was just hoping someone else came across this problem and found a way to rectify it.
     
    #4 Maxvision, Jan 15, 2010
    Last edited: Jan 15, 2010
  5. Elmo

    Elmo New Member

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  6. Cabinfever1977

    Cabinfever1977 New Member

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    If you want your peddal sprockets to last with a shfit kit,buy some better ones.
     
  7. Pablo

    Pablo Master Bike Builder & Forum Sponsor

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    I'm on my second year of my shifter kit with my same gear cluster cassette and no bend/missing teeth. I shift hard all the time - in an attempt to break stuff. I think the key may indeed be the quality of the stock gears, but chain tension and derailleur setting are very important as well.

    People have broken and bent weak axles, one or two have broken derailleurs but I can't remember anyone tearing teeth like other than the time the guy (who never rode a MB at all before) somehow crashed Jim's bike.
     
  8. BarelyAWake

    BarelyAWake New Member

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    I suppose you've prolly thought of this - but have ya checked sprocket alignment? I was just thinkin' if it's too far out and/or your real axle isn't straight, that would explain the twist to the teeth you described and I'd imagine they wouldn't have much strength laterally so that'd break 'em... but I'm just guessin' here *shrug*

    What brand cassette is it Maxvision? Mebbe it's a bad 'un?
     
  9. Elmo

    Elmo New Member

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  10. Maxvision

    Maxvision New Member

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    Ya know what...alignment just might be the cause. I changed my rear innertube from a flat the other day, forgot to tighten the axel nuts, went for a short ride and...well, you can figure out the rest. Wheel didn't come off but it sure came out of alignment... Was just about the same angle and the teeth on my gears are now.

    Thanks for the post BarelyAWake
     
    #10 Maxvision, Jan 16, 2010
    Last edited: Jan 16, 2010
  11. BarelyAWake

    BarelyAWake New Member

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    "real axle"? o_O meh... typos lol

    I hope that's it, other than havin' to get a new cassette it's a simple enough "fix" FTW... and it served as a warnin' to me to keep an eye on mine, so thanks fer that ;)

    I've got set screws on my Rollfast's dropouts for just that problem... well actually "screw" as I'm missing one. I wasn't too worried about it till you made this thread - now I'm gonna hafta hunt up another sos I can sleep at night lol
     

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