Bicycle Mechanics - Seized bottom bracket in carbon frame

I just bought a used 2 year old carbon frame that I am planning to build up as a trainer. However, when I stopped by my LBS today to pull the bb, it appears to be seized/stuck pretty good. I trust the knowledge of the two guys working on it, and they wanted to stop cranking for fear of doing some serious damage to the frame.Does anyone have any ideas on how to break it loose, or any antiseize agents that may help out. The lugging and bb shell are alu, but there was some discussion on some agents that may not react well with the carbon.

What frame is it?

What side is stuck - is it both? If it the fixed side, you may be able to remove the other cup and get some WD-40 in the backside, this way it won't touch the carbon. In the past when I had a stuck BB, I attached a 4' cheater bar to a 1/2" breaker bar and stuck the BB tool on the end of that. I had my friend push it into the BB (as not to strip the splines) while I slowly applied pressure to the top of the cheater. I never had to push very hard before one would break loose. However, I never had to deal with a carbon frame.

What happens if you get WD40 on the frame?

What happens if you get WD40 on the frame?
Nothing! I have had Carbon frames for years and WD-40 doesn't affect them at all. It is a solvent, but only for oil and grease not plastic or carbon fibre.

CHEERS.

Mark

If it doesn't go, force it!

Just kidding...I would figure a breaker bar is the way to go...you can move the earth is you have a big enough lever.

PJ

Very carefuly cut the bottom bracket shell in several places and pry out the sections.

you are kidding, right? not sure here...

If the bb shell is Al. I would try to clamp that part so I am only applying torque to the AL and not the carbon frame. I would also try to get som WD40 in there.

Let the WD40, or plusgas whatever solvent you use, lay there for a few days.

Is this an old-style Fixed Cup or a cartridge (Splined) cup? If it's an old-style this did the trick(http://www.sheldonbrown.com/tooltips/bbcups.html), but I still needed a breaker bar, a box end wrench on the end of that, and me sitting on the bike using my leg to push down in order to break the cup free.

If it's splined and you don't have a buddy to hold the spline tool, a "Quick Grip" or woodworking bar clamp is a great way (probably even better than a buddy) to hold the spline tool so as to not strip out the splines.

Epoxy is pretty chemically resistant as plastics go. Only solvents like acetone, toluene, and methyl ethyl ketone (MEK plastic cement) will thin or dissolve epoxy. WD-40 should be fine, but if you are still worried, spray it on part of your frame and see if it melts the epoxy like plastic cement.

So why do ppl worry about using grease on seatposts and such with carbon frames?

If it's splined and you don't have a buddy to hold the spline tool, a "Quick Grip" or woodworking bar clamp is a great way (probably even better than a buddy) to hold the spline tool so as to not strip out the splines.

Ooooohh - I like, very good idea.

Heh heh, yeah you get these great ideas at 2:30 in the morning and can't find anyone to help you wrench on your bike :)

prestonjb, since carbon doesn't rust, there's no need for grease. It just makes a mess.

If it's splined and you don't have a buddy to hold the spline tool, a "Quick Grip" or woodworking bar clamp is a great way (probably even better than a buddy) to hold the spline tool so as to not strip out the splines.


Thanks for all the suggestions. After getting some solvent in and letting it soak for a few hours I was able to use a variation of the "buddy method" outlined above. Still had to crank long and hard, but it worked.

Just as a side note...if you don't already, I highly recommend wiping down your bike after each ride, and definitely using a towel or something to catch your sweat if you are on rollers or a trainer. It appears that the bb was seized in the threads by salt deposites from body sweat that had started to corrode. And if you do tend to excreed more than your fair share of bodily fluids, it probably wouldn't hurt to pull the bb at least once a year to relube (also remove your bar tape and stem to clean the crap out there too).

I try to wash my bike and polish it after a dirty ride. I use regular automotive paste wax. James