Chain slack adjuster taking power?

Discussion in 'Motorized Bicycle General Discussion' started by jbcruisin, Jul 20, 2009.

  1. jbcruisin

    jbcruisin Active Member

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    I have an EZbike with the Hueshang engine & use the rear chain adjuster. A friend has a 2 cycle & didn't use the chain adjuster until recently. After he put it on he said he noticed a slight loss in power. Is this true? If it is I'll remove mine & readjust my chain to run without it.
    Jay
     
  2. Creative Engineering

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    It is true; but the likelyhood that it would be, "seat-of-the pants", noticeable is slim unless it was installed totally wrong.

    As long as you install the tensioner correctly...i.e. the plastic guide wheel is in-line with the chain, and the chain has 1/2" of up-down movement on the slack side, you will not notice a loss in performance.

    Anything that adds friction to the assembly will result in some loss of power to the rear wheel.

    Jim
     
  3. jbcruisin

    jbcruisin Active Member

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    That's what I thought too. I knew it would put a little more drag on the chain but was surprised when he said he noticed a difference.
     
  4. 2door

    2door Moderator
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    Jim is correct. If the tensioner is installed right the difference in power drain would be negligible. In fact so small that I doubt seriously that you could tell. We're talking about micro differences in torque and we humans just don't have the ability to feel that small of a difference. My guess would be a difference in sound that your friend is hearing leading him to believe that the tensioner was draining power. The psychological aspect is probably responsible for the perceived difference, not the tensioner wheel.
    Tom
     
  5. azbill

    azbill Active Member

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    mine is spring loaded and even if I tension it so i can barely move it by hand, it doesn't noticeably affect the speed
    [​IMG]
     
  6. RPM

    RPM New Member

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    Azbill, is your spring loaded tensioner a modification of the original? I can never seem to get the sprockets aligned perfectly center on the wheel. I always have tight spots and have to adjust the tension of the chain based on that. I've been looking for something simple like you have.

    RPM
     
  7. azbill

    azbill Active Member

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    yes, I added the piece the wheel is mounted to
    (just a piece of flat bar with 3 holes)
    the hardest part was spacing it so the wheel was over far enough

    I used to use a tall 2 bolt tensioner and I crushed my chainstay trying to keep it from rotating
    (in pic in front of tensioner)
     
  8. jbcruisin

    jbcruisin Active Member

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    You should sell those things Bill. I'd buy one. I'm going to have to make one for my bike.
    Jay
     
  9. RPM

    RPM New Member

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    I did the same thing on my bike Bill not because it wasn't tightening up but because I didn't know when to stop. I realized too late what I had done and almost had a heart attack because it was on my 67 Sears all chrome Fleetwood.

    Its still that way now but I have to take the rear tire off and replace some spokes. I'll try and realign it all back up again. (little more experienced now) If there is still tight spots in the chain I'll try what you have. Thanks for the photo Bill.

    RPM
     
  10. Just_Gassit

    Just_Gassit New Member

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    Tight spots, ya, I've battled those. My kit had a pretty crappy 44t sprocket and I had to file it to get the crap chain to even run reasonably though it. I finally bought a quality chain and it made a world of difference. The cheap chain streaches alot and unevenly. Toss the junk chain, you will be much happier. I use shims under the rear motor mound to adjust chan slack, if it's too tight, yes, you can feel the power draw in the tight spots. Best to not run it like that. The auto tensioner is nice work BTW.
     
  11. xlite

    xlite New Member

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    "Tight spots" were often blamed on cheap chinese sprockets but actually due to uneven chain wear (not stretch). I actually went so far as to chop up and re-assemble sections of worn-in chains to get consistant tension.
     

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