My Ultegra (triple) bottom bracket is almost 4 years old, with about 5000 miles.
Recently, after cleaning and overhauling my bike after a lot of wet weather riding, I noticed that the cranks seem to spin sluggishly. Specifically, when I spin the crankarms, without a chain and on a workstand, the crank will spin about two revolutions on its own and then stop. Furthermore, I noticed that the spindles of the BB are rusting (spindles where the crank arms attach). On the positive side, I don't detect any play or noise when riding.
As I understand it, no maintenance/lubrication is required or possible on this BB. Given what I've said here, is it time to replace the BB? If not, is there ANY maintenance that I should be doing?
Originally posted by blaxx My Ultegra (triple) bottom bracket is almost 4 years old, with about 5000 miles.
Recently, after cleaning and overhauling my bike after a lot of wet weather riding, I noticed that the cranks seem to spin sluggishly. Specifically, when I spin the crankarms, without a chain and on a workstand, the crank will spin about two revolutions on its own and then stop. Furthermore, I noticed that the spindles of the BB are rusting (spindles where the crank arms attach). On the positive side, I don't detect any play or noise when riding.
As I understand it, no maintenance/lubrication is required or possible on this BB. Given what I've said here, is it time to replace the BB? If not, is there ANY maintenance that I should be doing?
That sure is a lot of drag on the crank....I say you're overdue for a new BB cartridge.
Originally posted by boudreaux There can be alot of Drag on the seals.If it's not rough ,noisy, or making crunchy noises and has no play I would not bother.
Originally posted by boudreaux There can be alot of Drag on the seals.If it's not rough ,noisy, or making crunchy noises and has no play I would not bother.
Fair point. The statement that it only spins for two revolutions before stopping doesn't really tell us if the drag is normal or excessive....don't know if he's talking about a good hard spin, or just light spin with one finger.
My Ultegra BB needed replacement a couple of years ago, and it was making the crunchy noise you describe. Agree that would be a normal indication of failure.
Suppose taking it to the LBS would be way to get good diagnosis before spending money on a new BB. With the rust, years, and miles, I'll bet it's time to change though.
Originally posted by dhk Fair point. The statement that it only spins for two revolutions before stopping doesn't really tell us if the drag is normal or excessive....don't know if he's talking about a good hard spin, or just light spin with one finger.
My Ultegra BB needed replacement a couple of years ago, and it was making the crunchy noise you describe. Agree that would be a normal indication of failure.
Suppose taking it to the LBS would be way to get good diagnosis before spending money on a new BB. With the rust, years, and miles, I'll bet it's time to change though.
Dan
5000 miles should mean nothing to an ultegra BB,but one could get a lemon, years mean nothing, as being well sealed it's unlikely to be full of spider eggs from non use,and rust on the spindle is meaningless.
Originally posted by dhk Mine was about 8 years old and had maybe 10 thousand miles when it got crunchy. How long do you think they should last?
Dan
I've heard of over 10 and less than 5,but suspect the lesser ones were lemons. also depends on rider weight and strength. The square taper un-72s often went over 20k, but the new splined stuff has smaller bearings to make room for that bigger stiffer spindle.
OK, thanks. Mine is the old square one. When I first got the bike in 92, I did a couple seasons of weekly crit races, so stood on it pretty hard back then at about 185 pounds. At least they aren't costly to replace (relative to other stuff today).
A good idea with replacing Bottom bracket is to seal up the shell with silicone to prevent water coming down the seat tube an into the BB. Water will sit inside your frame and ruin steel frames.
Originally posted by dhk Fair point. The statement that it only spins for two revolutions before stopping doesn't really tell us if the drag is normal or excessive....don't know if he's talking about a good hard spin, or just light spin with one finger.
<snip> Dan
Dan:
Let me clarify the number of revolutions vs. the strentgth of spin.
The two revolutions I mentioned are after a reasonably firm spin of the crankarm - not a light spin with one finger. Spinning the crankarm as hard as I can without knocking the bike off of the stand, I can get the crankarm to do 4.5 revolutions max on its own.
Originally posted by boudreaux I've heard of over 10 and less than 5,but suspect the lesser ones were lemons. also depends on rider weight and strength. The square taper un-72s often went over 20k, but the new splined stuff has smaller bearings to make room for that bigger stiffer spindle.
boudreaux:
Just to clarify, I am on the heavier side, pounding on my pedals at 220 lbs., and doing so climbing the aggressive hills of Northern California.
Originally posted by pudster A good idea with replacing Bottom bracket is to seal up the shell with silicone to prevent water coming down the seat tube an into the BB. Water will sit inside your frame and ruin steel frames.
Use grease on the BB threads,and sealing the threads does nothing to keep water from coning down the seattube. There is a reason for drain holes in BB shells.
I have an old Raleigh 6 speed mountain bike. Lately... something has felt/sounded amiss in the drive train... but I can't pinpoint where it is cause it only happens when there is some torque on the pedal.
I feel it most in the pedals and would have to describe it as cogs not quite connecting cause it has a brrr feel to it and it does it in every gear.
But... the rear derailer has quite a squeak to it... dispite oil... so I'm wondering if it comes from there.
