Should I use this?

Discussion in 'Motorized Bicycle General Discussion' started by Schwinn the Fox, Dec 30, 2010.

  1. Schwinn the Fox

    Schwinn the Fox New Member

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    Should I use this chain tensioner? It came with my kit. People have been telling me that they fall into the spokes and ruin your back wheel. People have told me that it can bend in and throw you right off your bike from dead stop.
    .bf.
    [​IMG]
     
  2. GearNut

    GearNut Active Member

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    I will never use one. You can run an aluminum strap from the seat stay to the chain stay and support them to prevent them from rotating into the spokes though. Someone on this forum or the "other" forum had a photo of one that they made. It was simply zip-tyed to the frame (2 on each end of the aluminum strap) and they replaced the bolt for the tensioner wheel with a longer one that would pass through the tensioner, tensioner wheel and support strap. They used a custom filed to fit spacer in between the strap and tensioner wheel to allow full tightening of the bolt through the whole assembly so everything was good and tight. Just be sure that the wheel will still roll freely.
     
  3. mikewayne

    mikewayne New Member

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    you should really take care of this part... proper greasing and maintainance will do well... you should be able to properly install this part as you said it can mess up your back spokes.... it this all is done then there are no worries.... best of luck!!!
     
  4. Allen_Wrench

    Allen_Wrench Resident Mad Scientist

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    A great deal depends on the kind of frame you have and the size of your drive sprocket. If you can run your drive chain to your drive sprocket with tension above and below - AND it doesn't rub on a chainstay, or even come near one - then don't put a "tensioner" on at all. Adjust the length of your drive chain so you can slide the rear wheel back to put tension to it. Then use the chain guide/tensioner on the pedal side if you need to. I think that's the best way, if you can pull it off.
     
  5. wayne z

    wayne z New Member

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    Hey Schwinn, I'm the guy that used the aluminum strap/zipties to stabilize my tensioner. My bracket is longer than yours, and there was enough room to drill a 1/4" hole close to the top corner to bolt on the strap.
    I used a 5/16 nut and some flatwashers as spacers between bracket and strap(3/4x3/4 aluminum angle from hdw store. See pics.

    DSC_1389.JPG

    DSC_1390.JPG
     
  6. wayne z

    wayne z New Member

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    Forgot to mention you may need to use a large adjustable wrench on the bracket,below the slot, to bend a slight twist into the bracket, to make it parallel with the chain.

    Wayne Z

    I noticed your bracket is much shorter than mine, so there will be less leverage to pull it towards the spokes. yours has 4 bolts too mine has only 2
     
    #6 wayne z, Dec 31, 2010
    Last edited: Dec 31, 2010
  7. wayne z

    wayne z New Member

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    Here's another one I just did today.
     

    Attached Files:

  8. GearNut

    GearNut Active Member

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    Well, I almost remembered it correctly...... :oops:
     
  9. Nougat

    Nougat New Member

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    The one I have is a two bolt bracket, not a four. I had to replace the stock bolts and nuts, because they'd strip before they got tight enough to hold the bracket steady. I've never had a problem, and I've got roughly 500 miles on it.

    Note that it's not supposed to be super tight on the chain. There should still be about 1/2" of play in the bottom side of the chain run. People who are having issues with the bracket falling into the spokes either don't have the bracket tight enough on the frame, or have the chain tensioned too tightly.
     
  10. Goat Herder

    Goat Herder Gutter Rider

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    When you peddle and drop the clutch to start the engine the opposite side of the chain gets tight against the teinsioner. Hence forth the need for the slack. The best set up for those that have the unforgiving frame /chain clearance issue is a spring loaded teinsoner. IMHO

    I have ran both designs stock and a spring set up both are very do able. I have a buddy that made a spring loaded set up that is flawless. He originally tried a rear suspension single left side drive, but his pivot point not being in the optimum position with the motor output sprocket gave him grief.

    So he put a all thread adjuster where the rear shock went to make a long story short. Adjusted his chain tension once and never touches it. I really liked the way his ended up. And a skate board wheel is way smoother than the stock wheel too IMO.
     
  11. Nashville Kat

    Nashville Kat Active Member

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    They are heavy- wish they'd make it lighter. I've seen them here with a set screw put through the middle to stop it from rotating on th eframe- i don't think it would break otherwise.

    A derailler works great on the pedal side- if you build more- it tensions that side so the motor chain can be pulled tight if there are no other clearance issues with the chain stays, a cruiser usually has the best clearance but not often a derailleur and fitting handbrakes can be tricky without larger wheels-

    so look for multispeed cruisers with cantilever brake fittings- my micargi even had a grooved hub that fit the sprocket-

    1/2 links are available for both the motor chain and pedal chains and can usually be used to get a workable balance between the chains without using this heavy tensioner if there are no frame clearance issues

    although breaking and resizing chains has always been about my least favorite mechanical thing with bicycles...
     
    #11 Nashville Kat, Jan 1, 2011
    Last edited: Jan 1, 2011

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