Bike Forums - Bottom B problem?

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Bottom B problem?

So I have been feeling/hearing this... grinding noise coming from my BB (i think?) when I'm really mashing hard on it (climbing etc). Grinding is kind of the wrong term. It is more like I can really feel the bearings moving instead of them being super smooth. Like they aren't greased enough. But the BB is a shimano sealed that has only been in the bike for a month. I was totally smooth when I put it in. Could there be crap somehow stuck in/around it giving it that feeling?
-Jarrett

i hear that when my chain is too tight for its own good, or not lubed properly.

take your chain off and spin the cranks, to see if it really is the bb.

is the bottom bracket still properly installed, are the cranks attached securely? something could be working its way loose.

It could just be grit in the chain.

also check loose chainring bolts.

Quote:

Originally Posted by RETTWINS (Post 2113597)

I have the exact problem on my one day old Redline 925. Did you ever find out the source? Any one else have any ideas?

I will check the cranks and chain ring bolts.

TIA

Take off your crank arms, take the bottom bracket tool and take out the bottom bracket. Clean out the threads and apply grease. Install the bottom bracket as tightly as possible. Tighten your crank arms so their tight enough to be stationary but without stripping the bolt and/or over tightening them; grease every thread. Clean your chain and tighten the chainring bolts and grease the bolts and lubricate the chain. Make sure your cog and lockring are cleaned and greased and tight. Tension your chain properly as well.

Is your chainring and cog both the same pitch? Is your chain 1/8 inch and the chanring and cog 3/32?

There really isn't that much that can go wrong. I find that if I spend the money on really nice parts and figure out how every tiny thing involved works together properly, I don't have that problem.

I did however do some pretty sketchy things when I first started repairing and servicing bicycles out of ignorance, so I can relate to the random noise and not knowing where it's coming from.