Bicycle Mechanics - Bottom Bracket Noise - How Serious?
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2008 Windsor Cyclo with "FSA Omega MegaEXO External Bearing"
My last bike had a very similar clicking type of noise when I pedaled hard, and the shop just had to tighten the bottom bracket.
I've started getting that same noise now on the cyclo. The problem is my car got rear ended and will be in the shop, so the bike is my only transportation. I'm reluctant to hand it over to my shop for 2-3 days. Besides, the shop closes before I even get out of work, so I'd have to wait until Saturday anyway.
A) Can I ride it for the time being without doing damage or risking any sort of failure in the BB? I have a 10 mile commute one way. Hilly at some parts.
B) Is this something I can do myself? I like wrenching on things myself, but I don't have any bike tools, and more importantly, I don't really have any spare time. A 30 minute job will probably take me 3 hours to learn while I go. But if it's just a matter of turning a couple of screws, then I'll do it.
Thanks in advance.
05-21-09, 02:16 PM
i had the same clicking on my megaExo BB/gossamer setup. It seems to have stopped after I messed with it a couple weeks ago. I removed the left crank arm, greased the splines, and re-installed the crank arm. Its not bad, just two screws and the end cap.
The two bolts that hold the crank arm on should have blue loctite on them, but you can re-use them. I think a 6mm hex bit was all that was needed, but I would suggest a torque wrench. Installation instructions and torque specs are found on FSA's website. One thing not mentioned there, be sure to alternate between the two screws as you tighten them down, so they come up to the proper torque gradually and in sync with each other.
Thanks! If that's all it is, it's worth a shot.
I see one hex screw here, but I can't tell what is in the hole next to it. These are the screws in question?
As for the end cap, just tighten it clockwise with whatever wrench or pliers I can use? How tight before it's too tight?
05-21-09, 03:18 PM
that looks like a slightly different design for the crankset. Thats the correct hex screw, the other one screws in from the opposite side of the crank arm. I think the end cap should also fit a hex bit. Here's a PDF with the install instructions:
It has an exploded view which should help you out. Since you have the Omega crankset, your bottom bracket should be the BB-4000 model (see the bottom of page 3 of that PDF).
On my gossamer crankset, the end cap and two fixing bolts used a 6mm hex bit so you shouldnt need pliers or a wrench. The end cap bolt is only for setting the right pre-load on the bottom bracket. Its torque spec is only ~5 inch pounds (less than 1 pound of pull on a 6" ratchet). The two fixing bolts are much higher and you should probably use a torque wrench.
Well, I got the left crank arm off easily, but I don't see the point of that. There was nothing to grease, nothing else that I could take off (the cup apparently needs a special tool). and when I put it all back together it was the same clicking.
Unless I'm missing something that's supposed to be obvious.
05-21-09, 07:59 PM
Here's a pic of mine with the crank arm off. The splines are the raised "teeth" on the shaft. I put a bit of white lithium grease between them in the area marked in red.
Had my mechanic take a look at it. The BB was indeed quite loose.
But even tightening it didn't make the noise go away completely. After taking off the left cup and giving it a few spins, the bearings seemed just a bit gravelly. But there's no play, so that's good news. I guess I'm going to get some more mileage out of it before I spring for a new cup, or maybe a whole new BB.
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