|grinding noise around BB||wulf|
May 22, 2002 1:50 PM
|Guys - I finally got around to cleaning my disgustingly dirty drivetrain (irresponsible), and after I got everything shining again, and had my ear down near the BB, I hear a grinding noise. Actually, more "gritty".
I can't get in there to see if it's just surface crap due to the crank being in the way (which I don't know how to remove). I read on the Parktools site that if you can pinpoint this "grinding" or "gritty" noise to the BB area, and the chain/cranks etc. are fine, then you need a new BB.
Really? I did have the bike built up by a friend using mostly "slightly" used parts (he's a good guy, I'm sure he didn't screw me on this), so if it is shot, and it's this grinding noise, what has happened? Is stuff getting into the BB? was it bad to begin with? a BB lasts for WAY more miles than I have logged...
|Get a feel for it||Kerry|
May 22, 2002 4:51 PM
|Your best bet is to remove the cranks and turn the BB axle in your fingers. You'll easily feel if there's grinding or grittiness. Next best bet is to try to do the same thing, but leaving the cranks on (let the chain drop off the small ring and rest on the BB shell). Not as sensitive a test, but may still tell you something. You didn't say how long you've had the bike, nor whether you ride in the wet a lot, nor how many miles you have on it, etc. So there's no way to even guess at the answers to your last few questions. BTW, even if the BB is grinding, you don't have to replace it right away. It may get worse, but it's doing anything more than maybe adding a little resistance to your pedaling.|
|Your best bet is to remove the cranks. . .||czardonic|
May 22, 2002 5:14 PM
|It is a simple job, but you'll need a crank puller. It could be that while you were cleaning everything else, you washed some grit into the gap between the crank and the BB. If so, all you'll need to do is clean out any gunk, making sure not to drive it into the BB itself. It the grit has already penetrated the BB, your options depend on the kind of BB you've got. If it is the non-cartridge type (i.e. you can remove and seperate the cones, bearings, spindle etc.) then you just need to clean and re-pack it with new grease. If it is the cartridge type (i.e. it unscrews as a solid body, usually with a special splined tool) you may have to replace it as they are not designed to be serviced. However, as was said above, a gritty cartridge BB is only really damaging itself, so it's not a huge deal other than the increased resistance. You may even find that the grit is eventually ground down enough that the problem solves itself.|
May 22, 2002 8:57 PM
|sorry to leave out the details...
- It's an ultegra BB, double.
- I've only had the bike since October, but I don't know if the BB was used, or new (probably moot, see next point).
- I have put less than 1000 miles on it.
- I rode in the rain ONCE - 2 weeks ago, for about 25 miles.
It sounds like I should pull the cranks, regardless, to check out WHERE the grit is. It sounds "superficial" to me, but with the cranks on, I can't get to it.
Question: the cranks are on there with an 8mm bolt. I tried turning those bolts, both ways, and they seem to stop in both directions. Are they reverse threaded (ie. not left loosy, etc.)? I got a little nervous when they stopped going both way, and just decided to wait until I could get advice from you guys.
Hope this helps clarify.
May 23, 2002 3:53 AM
|use an alen key to unscrew both cranks to the normal direction (anti-clockwise) and the crank will come out itself.
To unscrew the BB you must find out if it is English or Italian threaded. But it is sealed type so you cant open it, just clean it at the outside.
|just unscrew them||weiwentg|
May 23, 2002 7:01 AM
|they are self-extracting. when done, screw them back on.
if the BB is gritty, all you can do is replace it. if you're like grzy you could open it up and service it, but that's difficult. and they're not expensive.