Another bb question
02-20-14, 09:50 AM
#1
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Thread Starter
Another bb question
Real quick,
I noticed on my bike last night, that while I'm off the bike, if I backpedal, when my cranks are in a certain spot, it gets some slight drag. Theres also a very soft noise that sounds like when you have brake pad just arely hitting your rotor. It definitly is in the bb area, and is not noticable when on the bike.
It feels a bit like a tight spot in my chain, but the chain tension seems to stay the same, and theres that slight sound.
I was gonna go on a ride today, but dont know if that's a good idea.
Thnk I'm okay if it doesnt seem to do it while I'm on the bike? The bike is 2 weeks old with 20 miles on it. Could it just need breaking in?
It's an eccentric if that matters.
Thanks.
I noticed on my bike last night, that while I'm off the bike, if I backpedal, when my cranks are in a certain spot, it gets some slight drag. Theres also a very soft noise that sounds like when you have brake pad just arely hitting your rotor. It definitly is in the bb area, and is not noticable when on the bike.
It feels a bit like a tight spot in my chain, but the chain tension seems to stay the same, and theres that slight sound.
I was gonna go on a ride today, but dont know if that's a good idea.
Thnk I'm okay if it doesnt seem to do it while I'm on the bike? The bike is 2 weeks old with 20 miles on it. Could it just need breaking in?
It's an eccentric if that matters.
Thanks.
Last edited by Shinkers; 02-20-14 at 12:26 PM.
02-20-14, 12:26 PM
#2
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Thread Starter
Anyone? I went out and took the chain off, and it's definitely in the BB or the spindle or something like that.
02-20-14, 06:30 PM
#4
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Two weeks old? Take it back to the shop. If there's something wrong with it, they should make it right.
02-20-14, 08:10 PM
#5
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I'm going to go out on a limb and assume from the description that you neglected to mention that it's a single speed bike. If so, that would be key.
Odds are the chain is too tight. You say the tension doesn't change so I suspect that it's too tight.
If you have a blackboard please write the following 100 times.
THE CORRECT CHAIN TENSION IS ZERO TENSION.
Adjust the eccentric, or move the wheel so the chain is never under tension as you back pedal through a few revolutions. Ideal is slight, minimal slack at the tightest part of the cycle, or roughly enough for the middle of the lower loop to move up and down about 1/2" total (1/4" in each direction).
BTW- for future reference, describe the problem, AND provide enough info about the bike or affected parts so readers might be able to help.
Odds are the chain is too tight. You say the tension doesn't change so I suspect that it's too tight.
If you have a blackboard please write the following 100 times.
THE CORRECT CHAIN TENSION IS ZERO TENSION.
Adjust the eccentric, or move the wheel so the chain is never under tension as you back pedal through a few revolutions. Ideal is slight, minimal slack at the tightest part of the cycle, or roughly enough for the middle of the lower loop to move up and down about 1/2" total (1/4" in each direction).
BTW- for future reference, describe the problem, AND provide enough info about the bike or affected parts so readers might be able to help.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
02-20-14, 09:01 PM
#6
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I would agree that a 2 week old bike should be taken back to the shop and checked.
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02-20-14, 09:06 PM
#7
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I missed the reference to the chain being off which was in his next post. 20:1 he's simply obsessing about seal drag or the like, but sure with a new bike, letting the shop check is usually the best course of action.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
