Bicycle Mechanics - over-torqued BB removal techniques?

well, brilliant me has over-torqued the BB on my bike. =( i'm assuming it's a shimano ES-71 as the crankset is the matched XT, and it has the aluminium rings (not plastic like on the UN53's).

i've gotten the lock-ring off, but in the process of figuring out which side it was on, over-tightened the main-body side.

anyone ever do this, and how'd you get it off eventually? my entire body weight on the wrench isn't budging it =( and using hammer+wrench isn't getting it to move either.

thanks for any suggestions

-chris

Have you tried a cheater bar? And make sure you're turning it the right way. ;)

Soak it in liquid wrench or some other penetrating oil overnight then try it again.

Be sure you are loosening the correct way. The drive side is a left-hand thread, remove it by turning clockwise.

You can hold the tool firmly to the cup with a long bolt, or a skewer if it is a hollow axle.

http://www.parktool.com/images/repair_help/bbtskewer.jpg


See also Bottom Bracket Service (http://www.parktool.com/repair_help/FAQcartdg.shtml)

Another way if you have a big bench and vise is to use the setup pictured by Calvin but clamp the nut in the vise with the frame horizontal and use the frame as the wrench. Make VERY sure you are rotating in the correct direction though, torque is enormous. Get another BB nut similar to the one you are removing and study the thread angle first. I tried this with an old screw on freewheel that was stuck on the hub and ripped the tangs off the freewheel remover and slightly twisted the freewheel body by rotating the rim with my hands.

dirtgrinder, not sure what a cheater bar is, but i gather it's like using a pipe to extend the leverage of the wrench. i may do that.

captsven, would i need to soak it from both ends? ie, should i submerge the entire bb assembly (i got the non-drive, lockring side off already).

calvin, i'm pretty sure i'm doing it the right way. all the pics of my bb show the threading on the drive side as you say, clockwise to loosen. i was using zip ties to hold it in place... geez, i should tried a skewer! doh!

sch, hmm, i don't have a bench handy, nor a vise. if the above don't work, i may have to bolt one to my desk or some such.

thanks for the suggestions guys! i appreciate it!

-chris

You can submerge it if you want to. I do not think it will affect the paint job.

I would just spray it on both sides and let it sit overnight. tapping on it occassionaly doesn't hurt either.


Is this an American bike. If it is Italian or something exotic, it could have an Italian thread. This would have to be removed in the opposite direction.

68= English
70= Italian
(Sometimes it is stamped on the cup)

Get everything setup and ready to turn the wrench and then pour some near boiling water on the BB shell.

I used a giant 1 1/4" box end wrench that happened to fit by bb tool perfectly. The wrench is so big it could be used as a deadly weapon. It did the job. So well, in fact, that I ended up stripping the splines on the left side cup. I had to lay the bike on its side and turn it a 1/4 turn at a time while putting all my weight on it. By the time I got it out there was nothing left of the splines. No biggie since I was replacing the bb anyway. Now I need to take the whole thing apart again to fix the creaking. It'll give me a chance to try out my crank extractor.

Originally posted by curisu
my entire body weight on the wrench isn't budging it =( and using hammer+wrench isn't getting it to move either.


My oh My. :crash: Maybe you can get a couple of bubbas to help. But,really I just don't know.