Bicycle Mechanics - Campy BB thread direction
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03-30-09, 02:20 PM
Sorry if this has been covered before, but I did a quick search and could not find anything.
I have an 07 Record 10 spd group. I am able to pull the crank arms off and remove the left cup, but I can't get the right cup (drive side) to budge. Unlike my Shimano bearing cups, there is not a direction arrow telling me which way to turn to tighten. I would assume that it would be turned clockwise, but that is not moving it.
Thanks in advance.
03-30-09, 03:12 PM
This has nothing to do with Campy/Shimano differences. Most frames have English BB threading that is left handed on the drive side, so you've been trying to tighten the cup. Italian threaded BB shells are right handed on both side.
03-30-09, 03:28 PM
Dave thanks for the reply. However, I am still confused, if it is left-handed on the drive side would I not turn it clock-wise to loosen? I am trying to get the cup off, but may not have made that clear in my original post.
03-30-09, 03:55 PM
Sorry, I didn't read closely enough. Yes, clockwise is the normal direction unless you have an Italian or Merckx frame. It's still not a Campy/Shimano problem, though.
if it's an italian frame, it most likely has an italian threaded BB.
should loosen if you turn it in the opposite direction.
if it doesn't, it could be rusted into place.
03-30-09, 08:09 PM
Key question: what brand of frame is it? What's the country of origin? If it's from Italy, it's likely Italian threaded (right hand thread both sides). Otherwise, it's probably English threaded (left hand thread on the right side of the bike, right hand thread on the left side of the bike).
Fixed cups on bottom brackets can sometimes be very, very difficult to remove, no matter what threading. Corrosion is usually the problem. I'm talking soaking for days with penetrating oil, fashioning imaginative high-torque tools, etc. And celebrating when it finally breaks free-:)
03-30-09, 08:39 PM
Check for engraving on either cup. If it says "36 x 24" then it's Italian; if "1.37 x 24" then it's English. Not all manufacturers put this info on their cups but all the Campy's I've seen have it.
Otherwise measure the bottom bracket shell. If it's 70 mm wide it's Italian; if it's 68 mm it's almost certainly English.
If all else fails, now that you have the adjustable cup out, try comparing it side by side to a spare cup whose threading you are sure about. Italian cups are of perceptibly wider diameter than English (36 mm is bigger than 1.37")
+1 that fixed cups can be very difficult to remove. Ask yourself if you *really* need to.
03-30-09, 08:51 PM
English cups will slide right into an italian shell. If you have some spare english cups from any BB, you can check that way.
03-30-09, 09:16 PM
They are English. 1.37 x 24. Can't get the thing to budge. This is an 07 Fuji SL-1 frame. I'm installing an SRM and using the cable guide mounted sensor. I have the same problem with the screw holding the guide on. It was a Philips head with very soft metal and I stripped the head. Ended up cutting off the guide so I could get some channel locks on the screw and finally got it off. I have the cup soaking in penetrating oil. Hope that helps....
03-30-09, 10:56 PM
I just tried doing this myself and I couldn't get it to budge. But mine was a loose bearing type BB with an adjustable cup and a fixed cup, an 07 Campy must be a cartridge type, no? Maybe I'm wrong on that.
In any case I gave up and just repacked the BB with fresh grease. With a good adjustment the BB/cranks are as smooth as any I've ridden. It was an old Zeus BB, and I put a Chorus 10sp crank on it. It seems to work just fine.
you probably need more leverage, use a pipe to extend the handle for more leverage.
03-31-09, 08:50 AM
IIRC, Campy recommends installing the cups using Loctite 242 (Blue, medium strength) so it may take a lot of torque to free it up.
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