chain tension
11-30-09, 09:08 PM
#1
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chain tension
Is it normal for my chain to get looser as my pedals rotate. There's about a half inch of slack half way through the rotation and an inch of slack on the other half. Just curious.. Never had this before.. Thanks
11-30-09, 09:12 PM
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cab horn
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Almost all fixed gears will do this. Extremely high quality parts/frames will mitigate this effect somewhat.
11-30-09, 09:16 PM
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Most chainrings are not completely circular...hence, difference in tension throughout the pedal stroke. High end chainrings are much closer to completely circular than cheaper stuff.
11-30-09, 09:16 PM
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11-30-09, 09:43 PM
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12-01-09, 02:54 AM
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If it's just when you're pedaling don't worry about it. It's just some flexing in the frame or some such. If it is slack that goes in and out of your chain even with no pressure on the pedals, your chainring is out of round. This you should probably not worry about either unless it is enough to throw your chain during normal operation. Honestly if the chain stays on you should be fine. It may get annoying but it won't kill you.
12-01-09, 04:50 AM
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I don't think it's the chainrings aren't circular so much as that it's hard to get them perfectly concentric on the crank spider.
12-01-09, 07:16 AM
#9
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Its usually a bit of both. However, I have encountered numerous chainrings that are clearly not circular. As long as the chainline is reasonably straight, minor variance in chain slack/tension is not a big deal, although you may find it to be annoying when riding fixed.
12-01-09, 10:13 AM
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my first fix had the same simptoms , but it was a road bike chain ring...ever since I rode true track gear never run in to it again...
12-01-09, 12:20 PM
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looks like i shoulda dropped the $80 on the sugino messenger ring.. my bike is working but its annoying as hell.
and yeah, the tension changes even without pressure.
and yeah, the tension changes even without pressure.
