Santa Cruz Bronson, possibly first ever BB replacement. First cup came off fine with appropriate tool (respected guidance in BB cup showing which way to loose ) but needed decent amount of force, but I cannot for the life of my loose the non-drive side cup. My tool is right on the edge of properly stripping the cup threads now. Tried wd40 to loosen, tried extended wrench using breaker bar. Won’t budge. The cup I got off had no grease at all on inside of thread…thoughts?
by chrisevz1337
14 Comments
I can’t make sense of the photo lol. But we’re 100% sure you’re loosening and not tightening more?
Are you spinning the right way? The two sides are opposite of each other.
Edit: the bike is upside down, (on its seat and handle bars), and yes I’m respecting the arrow that shows direction to tighten. (So pulling /pushing in opposite direction, and yes they are different on each side – drive side BB cup came off fine)
https://preview.redd.it/1rmh9utfxmmc1.png?width=3024&format=png&auto=webp&s=2e94d3d66d980c1b66747c7f9d5d7b947789e35f
WD40 is not a penetrating oil. Try letting a penetrating oil soak in from all sides for a day or two.
Tried clamping some vice grips? The BB is shot anyway and those tools marks are useless now.
You sure you got the correct tool?
I have stood on a wrench/tool to break these loose and it did not roll the edges like this.
PB Blaster, etc is your friend here but make sure your tool has a good purchase.
Yeah the other side is reversed threads. You may be tightening it.
Assuming you’re turning it the right way, try Penetrating oil, a pipe wrench, and hit the end of the wrench with a mallet. I’ve had good success with this method.
If you’ve wrecked the tool interface and it’s garbage anyway, then you can use a pipe wrench.
If you can access a vice it can work well. Clamp the bb and turn the frame. Or a pipe wrench and a friend
1st try, do what others said and either clamp in a vice w/ tool or via bearing press to maintain full engagement and get a wrench over a foot long to help you. Cheater bar can aid.
2nd try, borrow an impact wrench, the 1/2in socket will loosen it like butter
3rd try and this is mostly a joke and I cannot imagine why you would ever need this, but if something got so galvanically seized, you would hammer out the bearing and Dremel/file or file most of the way through the BB shell, then use a punch to yield the threads then unscrew with chanellocks. Plumbers do this all the time on old siezed iron pipes.
I’d use a big pipe wrench. If that fails, I would grind flats into the BB cups, clamp it in a vise, and use the frame as leverage.
What about a socket bb tool and an impact driver?
The last resort is clamping the (correctly sized) bb tool in a bench vice and turning the frame after soaking in proper penetrating oil (eg. “Liquid Wrench”) overnight. Once it is clamped in the vice turn the frame to loosen the bb. Triple check you are turning it the right way – the drive (right hand) side is *turn the bb clockwise to loosen it from the frame*; non-drive (left hand) side is *turn the bb anticlockwise to loosen it from the frame*.
Edited to say: it looks like the reason it has never been removed might be that the bearings are re-packable – there’s a circlip in there – if you take it out, you will probably be able to (gently) remove the seal(s), degrease, regrease and re-use.
seized is the word you are looking for