bike has been left in the elements and short of a torch we have tried everything we can think of to remove this thing, broke a socket wrench and almost my co workers face. we've soaked the threads in pb blaster and a derusting solvant.
any thoughts or ideas would be appreciated
by jinxt92
24 Comments
Chill the bottom bracket and heat the shell for maximum thermal contraction/expansion benefit.
We have made good experiences with an impact wrench.
And also just in case, with turning the wrench clockwise on the drive side.
1. Are you turning drive side clockwise or counterclockwise to loosen?
2. If it’s that tight, never use a socket wrench. Use a 2 foot breaker bar. Or longer.
3. Have the bike upright with tires inflated to get leverage…don’t try to do this on a bike stand.
air impact, high flow compressor? Harbor freight has their 1200ftlb impact on sale right now.
If you have a bench vice clamp the BB tool in the vice and turn the bike. Just make sure you’re going in the correct direction.
for the toughest ones i’ve faced, clamping the tool in a vise and turning the frame has never let me down also, remember that drive side is reverse threaded (removes clockwise) except when they are not, i doubt that there is any splined rh/rh bb, but i guess it could be possible, won’t hurt to rock the frame back and forth in case it’s reverse threaded, even if you manage to tighten it, the fact that it moved at all will make removing it way easier.
You could try to chill down the BB with upside down canned dust remover and heat the BB shell with a hair dryer. That plus whacking the BB with a mallet a few times to try to break up the rust.
Put the tool in a vice and use the frame for leverage. Never had that method fail.
Good.luck.
Heat will definitely be the way to go. If you can get some penetrating oil in the threads and let it seep overnight before heating things up.
You have a good BB tool so don’t be afraid to put some effort into it. If nothing ends up working I’d suggest an impact wrench in combination with the above.
I work in a bike shop and this method has never let me down 🙂 best of luck OP
Edit:
While derusting solvent isn’t a degreaser it will have broken down the PB blaster regardless of the order you applied them.
I secure the BB socket and beat it out with a rubber mallet.
Man, sucks trying to get a stuck bottom bracket out. More leverage, I guess.
Have you hit it with the PB yet?
Heat my friend. Plenty of heat to the bb shell
Penetrating oil and some light tapping around seized area
Breaker bar. Torque is your friend.
Stick the tool in a bench vise and use the frame to turn against the bench
Any penetrating oil will help but the absolute best is a homebrew: half acetone, half automatic transmission oil. After you let that soak overnight, hit the shell with a heat gun. If you happen to have an impact driver, should zip it right out, but a wrench and a breaker bar is good too
I manged to get a really rusted in BB out by soaking it in derusting solvant multiple times over the course of two days. Then I fixed the BB-tool with a scew to the axle like you did and since I didn’t have a breaker bar at the time I just fixed a wrench to the tool and with the bike on the ground I then stood on the end of said wrench with my full body weight (over 100kg/220 pounds) at the time, which finally did the trick.
The threads on the frame were in remarkedly good shape and the owner is getting some good use out of the bike again.
You’re doing the right thing using the axle bolt to keep the spline tool from slipping out, BUT if you use an impact wrench (which is a good suggestion) be sure to leave some small space here for if (hopefully when) the thread breaks loose, then have cat-like reflexes to release the impact trigger!!! Using a stout bench vise is also good, but same warning, muscle inertia is harder to control than that trigger! For the person recommending heating and cooling parts that are stuck together, you will need a big enough freezer to swallow that frame and BB….. And if that works, heating the BB shell will need to be very rapid, or the delta temperature of the BB and frame will be very low. Might be possible as a last resort using dry ice and a torch?
I would try tapping on the shell with a dead blow hammer with tension applied to the BB tool. This could help to brake apart the seizing. Past that I would also try a heat gun. If you don’t care about the paint finish, a propane torch would be even more effective. Full disclosure, I am not a professional bike wrench, but I am a heavy truck mechanic, so no stranger to having to break really stubborn things apart.
Also, soak that thing in more PB Blaster and let it soak overnight. If you could submerge it in penetrating oil would be even better.
As you likely know, this has a left hand thread, thus turn clockwise to loosen.
Although you may be seeing surface rust, the seizing is more likely the result of galvanic corrosion than rusting. Aluminum + steel invites seizing. If you’ve been turning the correct direction, it’s quite possible someone did not apply threadlock or lubricant on the threads when assembling.
Heat will be counterproductive because Al alloy will expand more and at a lower temperature than steel.
If all else fails, you can carefully cut several grooves in the BB cup with a hacksaw blade, then pound it out in pieces with a hammer and chisel. I’ve done it several times, each time scolding the bike owner to clean the threads and apply liberal amounts of Loctite 222 or 243 when reinstalling.
However you remove it, I recommend chasing the threads with a proper piloting tap before installing new BB cups.
Aerokroil > PB Blaster
Impact > breaker bar
If no impact wrench, smack breaker bar with hammer. Sometimes multiple lighter whacks will help loosen. ☘️
Heating and cooling cycles are good at breaking up corrosion between the two parts.
Have you tired taking the seatpost out sparing your favorite rust resolver sit day and see what happens