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Spanner = beer in armadale today!

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Loz, Apr 9, 2005.

  1. Hi all -

    I'm 'round at a mate's place in Armadale. He was trying to tension the chain on an old CD250U and has somehow buggered it up. I'm not the most mechanical of blokes either, so I wasn't able to fix it, but I can say this much:

    The chain is now alternately loose and tight at different points in its rotation. As in, so loose that ity flaps all over the place, and so tight it's difficult to rotate the back wheel.

    I reckon the back axle's out of alignment but I'm not sure how to fix it. I'm sure it's a 10 minute job for any bugger that knows what he's on about.

    There's beer and BBQ snags, as well as at least a week's good karma in it for anyone who can help him get it on the road before work on Monday!

    Gimme a ring on 0418 219 330 if you can help out!
  2. His chain is stuffed and needs urgent/immediate replacement. What happens is that the chain gets tight spots in it, exactly as you describe. This occurs because some of the chain linkages no longer flex/bend because they have become worn. As the chain rotates around the (generally front because it's much smaller) and the linkage can't bend around the sproket, it lifts away from teh sprokect and therefore increases the distance of chain travel between the front and rear sprocket. Thsi cause the chain to tighten and loosen in various spots as you describe.

    Easy to check, just watch the chain at the bottom as you slowly rotate the rear wheel. You'll see it slacken and tighten as the chain rotates. Once it goes tight, the problem area of the chain is likely to be on the front sprocket, so just it a little more until that section is along the bottom half way between front and rear. Give the chain a bit of a flex with your hand at this point, and you'll feel the resistance. Get the chain and srockets replaced and you'll be fine.
  3. What Mouth said.
    Also there are notches in the swingarm which after you wipe it you will see them (near the wheel nuts obviously)
    Make sure they are aligned on both sides.
    As for tight spots I'm afraid the chain and sprockets will need to be replaced.
  4. Oops, just re-read and I missed the important point :)
    I could be that his chain is stuffed as I describe above, or that he's buggerred the tensioning and has the axel out of alignment as you describe :)

    If it's the latter, it will have markings on the swingarms near the tensioning point. Make sure they are in exactly the same spot on both swingarms :) Hey may have just adjusted the tensioner on the chain side, and not equally matched the adjustment on the other swingarm.
  5. Update -

    Using the notches on the swingarm, I made sure the rear wheel was in alignment and tightened everything back up.

    It's the chain that's rooted, and probably the sprocket too. There were some very stiff links in it. Unsurprising really as the bike's 60,000ks old and when I took a look it appeared to have 60,000ks worth of road muck stuck in it.

    Gave him a stern finger-wagging session on cleaning and maintenance of next chain, he'll get it into a mechanic's on Monday. It's rideable though not entirely safe... and we got stuck into the beer and snaggers ourselves!

    Thanks guys