Chain tension tightens then loosens????
04-08-16, 07:56 PM
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Chain tension tightens then loosens????
I have been riding fixed for years now but I have never come across this problem before. My chain tension keeps changing, one full revolution it is tight then another full revolution and it is considerably loose. I have just been dealing with it for a while because my crank gear is a 60t so the chain never really has seemed like it would jump off. I stand corrected, today it did. It jumped off, locked around my cog and I skidded to a stop. Needless to say I burned a hole through my tire and I manged to crack a euro-asia 21t cog--not happy about that. SO I have checked my bottom bracket and it is straight. I have checked my chainring, crank arm and axle and they are all perfect. I have even tried to center the chainring on the crank arm and it has had no affect. So I am completely at a loss???? Any Ideas????
Thanks.
Thanks.
04-08-16, 08:17 PM
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No, Standard chain ring. I commute daily in aero position and a large chain ring just feels better, also you don't get any dead spots that way. No need for an oval chain ring if you just ride a large one.
04-08-16, 09:00 PM
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Lol it sounds like your chainring is ovalized.
Gonna guess it's really old cause whered you get a 60t ring.
Gonna guess it's really old cause whered you get a 60t ring.
04-08-16, 09:10 PM
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It is not ovalized. I have used different sized chain rings 52, 54, 56 all new and it didn't changed anything. Also even if it was ovalized why would it be tight during an entire crank revolution they loosen up for another? It doesn't make since. You can get 60t chain rings on Ebay Bi King Driveline CNC 7075 Alloy Chainring 60T BCD 130mm 196G Black CP25F | eBay .
04-08-16, 09:15 PM
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Maybe your hub was warped? Have you tried a different wheel, crankset, bottom bracket? I would have taken it to my LBS to get it checked out
04-08-16, 09:23 PM
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Newer bottom bracket SKR BAS-600, have tried 3 different cranksets. I have not tried a different wheel. The hubs have sealed cartridge bearings, so there isn't any room for it to be warped. That is why I think this is so weird.
04-08-16, 10:06 PM
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Sounds like your chain is worn, if everything else is new.
04-08-16, 10:13 PM
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Have tried other chains and they do the same but creak really loud. I have been using a half link chain and it doesn't make noise.
04-08-16, 10:21 PM
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Maybe your cog was loose? There's only so many things it could be, so you're probably missing something fairly obvious.
04-08-16, 10:22 PM
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There seems to be a bend in the space-time continuum somewhere between your bottom bracket and your track ends.
04-08-16, 10:25 PM
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I just put another cog on it earlier and it is tight, still does same thing. This is why I haven't taken it to a bike shop. I have tried all of the obvious, I just thought I would see if anyone had any new ideas. Thank you for all of your replies and time.
04-08-16, 10:44 PM
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Check your chainstay and bb shell for cracks.
04-09-16, 05:38 AM
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Probably running with the chain too tight. Or could be the rear triangle is off a bit. Check it with the string test.
04-09-16, 07:27 AM
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What is the quality of your crankset? Of your chainring? Were they made to run fix gear or intended for use on geared bikes. Cranksets not made for fix gear riding often have lower standards for roundness of chainrings and accuracy of spider chainring bolt drillings because with a derailleur to handle chain slack, that accuracy which costs money in higher quality machining, etc. in simply not necessary. But a non-round crankset will cause the chain to do exactly what you describe.
Edit: I am surprised that non of the posters above have suggested this already. It is fix gear/single speed freshman 101.
Ben
Edit: I am surprised that non of the posters above have suggested this already. It is fix gear/single speed freshman 101.
Ben
04-09-16, 07:46 AM
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Thinking out of the box, but if the ring is round and the BB and wheel axles steady, I can see how a stiff or bent chain link could cause that.
Or, possibly, if the chain is so stretched out in places and very tight it might ride up on the cog or ring teeth?
Or, possibly, if the chain is so stretched out in places and very tight it might ride up on the cog or ring teeth?
04-09-16, 07:51 AM
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I was using an origin 8 triple crank before but I put it on my road bike. I am using an origin 8 track crankset right now and I get the same thing. I read that you need to center the chainring and I have done this a couple of times to no avail.
