Chain Length/Tension Question

Discussion in 'Motorized Bicycle General Discussion' started by shaggy, Mar 19, 2009.

  1. shaggy

    shaggy New Member

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    Had the chain all measured out, cut it and reassembled....but it still looked too long, even with
    the wheel pulled all the way back in the dropouts. So....I cut another link....now it's too short.
    I don't get it. How is tension measured?
    With the originally cut chain, the tension looked fine if
    I rotated the rear tire backwards, but as soon as the wheel rolled forward, the top chain would go
    slack and rest onto the bottom chain. (can't post a pic cause I already cut the chain again). Hope this
    makes sense......if not I will try and explain better. Thanks in advance.
     
  2. bnewman8629

    bnewman8629 New Member

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    I'm not quite sure what you are saying but let me see if I understand this. You cut the chain to where it was slightly taut on the bike. But when you rolled the wheel backwards then forwards there was slack? When you do this it created slack which brings the question, when in riding are you going to be going backwards? I think it will tighten once the chain actually moves forward. Have you ridden your bike yet, because it will natrually loosen a little bit. I'm sorry if I struck any nerves I may have misinterpreted what you were trying to say...
     
  3. toytime

    toytime New Member

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    I think I understand. I think you had slack in the chain at the bottom and as you rolled the bike forward, all the chain was brought up and around. Keep this in mind next time.
    Just try again, the chain can be put back together very easily, just smack the pins into place.
     
  4. shaggy

    shaggy New Member

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    Sorry I didnt explain better. With the chain at one length, it is too long...even with the tensioner wheel maxed out and rear wheel all the way back in the dropouts. I then cut only one link out and the chain is too short (with the wheel all the way forward in the dropouts and the tensioner wheel at its minimun setting. I need like a half link??
     
  5. toytime

    toytime New Member

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    That sounds so hard to believe. Are you sure your taking up all the slack?
    What if you don't use the tensioner at all? That's even better and less noisy.
     
  6. Shadeslay

    Shadeslay New Member

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    You can also adjust the tensioner by sliding it back towards the wheel dropouts. I had to keep mine way back towards the wheel dropouts, because no matter how tight I tightened the wheel of the tensioner it would always slide to the bottom, so to fix that problem I kept the tensioner wheel in the bottom position and slide the tensioner towards the wheel dropouts.

    Edit: truthfully you are likely better off keeping the wheel of the tensioner as low as possible. Less chance of it pulling into the spokes.
     
    #6 Shadeslay, Mar 21, 2009
    Last edited: Mar 21, 2009
  7. 2door

    2door Moderator
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    I'm still confused. How did you only remove one (1) link? Roller chain is designed in such a way that if you remove only one link you will end up with two male or two female (for want of a better term) ends to deal with. When you remove links you commonly remove two which will shorten the chain by that much. They do make what is called an 'offset ' or half link that will take care of your problem. I'm one of those who advise keeping the tensioner, especially if you're using the kit supplied #415 chain. It is usually poor quality and wears rather quickly requiring adjustment to keep the chain tension correct. I'd suggest replacing the kit chain with good quality #41 industrial grade chain but retain the tensioner. There is a lot of good information here on upgrades to the tensioner problems inherent with the 2 cycle kits. One that I would recommend is to attach the tensioner bracket to your chain stay with a screw or small bolt (I use a 10/32 cap screw, others use a self tapping screw) which will keep it from rotating into your spokes. It is critical that you get your chain/sprocket alignment correct before drilling and bolting the bracket to the frame however. As was suggested, moving the tensioner bracket toward the rear will tighten your chain. I suggest you get the tension close to right with the pully at or near the bottom of the adjustment slot which will give you room to adjust for more tension later when chain wear requires.
    As for rolling the bike and seeing slack. The recommended method is to roll the bike forward (engine off, obviously) with the clutch engaged and shoot for about 3/4" slack on the upper portion of the chain. 1/2" to 3/4" is a good point to be at. Give this a try and get back to us if you're still having problems.
    Tom
     
  8. shaggy

    shaggy New Member

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    Thanks for all the responses. I again apologize for not being clear....I should have said "2 actual links" taken out of chain. Thanks "2door" for the advice about the replacement chain....I have read that it is a worth-while upgrade, and I may do that soon. Also, thanks for the advice on how to properly mount the chain tensioner bracket...I'd hate to see it fly into the spokes on the first go around. Gonna fire up the bike for the first time tomorrow and see what happens....will work on the chain tonight. Thanks again.
     

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