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22 votes

Drive side part of bottom bracket is impossible to remove and has destroyed tool fitting

Unless your frame is Italian, or a handful of unlikely other makes, your bottom bracket is left-threaded on the drive side. https://www.parktool.com/blog/repair-help/bottom-bracket-removal-...
whatsisname's user avatar
  • 12.2k
9 votes

Drive side part of bottom bracket is impossible to remove and has destroyed tool fitting

The drive side was probably installed without anti-seize/grease, and has corroded to the frame. Presumably you want to save the frame and replace the cartridge. Starting with oils is a good first ...
Criggie's user avatar
  • 127k
6 votes

I crossthreaded the bike frame using force on the BB. Can still be saved?

The shifting problems are separate from the bottom bracket and frame problems. You've got a new crank installed, so it would be expected that the front derailleur and shifter will have to be ...
Nathan Knutson's user avatar
6 votes

I crossthreaded the bike frame using force on the BB. Can still be saved?

If the threads can be re-cut, as Michael suggests in the comments, try that first. If not, there are "rescue" bottom brackets that do not thread into the bottom-bracket shell; instead, they ...
Adam Rice's user avatar
  • 30.1k
6 votes

Removing a 1970s Schwinn Bottom Bracket

Alan is correct. Here's a diagram of this type of crank. Sheldon describes it with words but sometimes a picture helps. The left side in the picture above is missing both the locknut and the ...
David D's user avatar
  • 22k
6 votes

Removing a 1970s Schwinn Bottom Bracket

This is what's called a 'one-piece' or 'Ashtabula' crank. There is a nut you have removed (or that was already missing) on the threading. Then you remove the left cone via the slot in your second ...
Alan Gerber's user avatar
  • 1,515
5 votes

Broken plastic HollowTech II BB spacers, why?

That is a very weird situation because it sounds like you were taking more care than most and did everything right. If the torque wrench were somehow reading way under that could explain it, but it ...
Nathan Knutson's user avatar
5 votes

Threadlock for Bottom bracket on Titanium Frame?

The grey/white stuff on Shimano BBs is a mild threadlocker I believe. I normally put antiseize on top of it. The substance will still contribute a threadlocking effect by filling gaps, and you have ...
MaplePanda's user avatar
  • 15.8k
5 votes

Threadlock for Bottom bracket on Titanium Frame?

Use anti-seize on all threaded titanium BB shells. You're fine leaving the pre-applied threadlocker in place, or you could pick it off.
Nathan Knutson's user avatar
5 votes
Accepted

Stripped threads on the bottom bracket

Well, if the threads were chased with a tap, you might get purchase, but it sounds like you're not going to get that here. If it's a BSC/British thread, you can get the bottom bracket shell tapped to ...
Noise's user avatar
  • 14.4k
5 votes
Accepted

Drive side part of bottom bracket is impossible to remove and has destroyed tool fitting

I tried everything that Criggie said. Nothing worked but they were very useful advice. I managed to get it out by welding a 18mm socket on the bottom bracket's tool interface and then kicking the ...
Stelios Liakopoulos's user avatar
5 votes

Another very stuck bottom-bracket – non-standard size (37 mm flats)

Thank you all so much for your fantastic tips!! After much toil, this story now has a happy ending! First of all, after reading all your helpful posts, I took a trip to my local bike shop - they were ...
TooMuchCoffeeMan's user avatar
5 votes

Another very stuck bottom-bracket – non-standard size (37 mm flats)

There's a solution that is pretty likely to work: go to the "Fixed Cup Tools" heading on this page, which describes how to make and use this: This can be harmful to the cup, although not as ...
Nathan Knutson's user avatar
4 votes

Shimano BB: add grease over threadlock?

Grease on the threads of both the shell and cups is necessary to prevent galling the metal as torque increases to its final setting. The water proof quality of grease helps prevent ingress of water ...
Jeff's user avatar
  • 10.8k
4 votes

Drive side part of bottom bracket is impossible to remove and has destroyed tool fitting

Removing stuck bottom brackets where the tool interface is the 22-spline cartridge style and the splines are toast can be truly difficult, and the steps to take depend on the construction of the ...
Nathan Knutson's user avatar
3 votes

Broken plastic HollowTech II BB spacers, why?

I wouldn't be too worried. As Nathan said, you did everything right. By any chance do you remember what order you had the 3 spacers in? My guess would be that the two thinner spacers were being pulled ...
MaplePanda's user avatar
  • 15.8k
3 votes

Broken plastic HollowTech II BB spacers, why?

I would suspect the stackup of spacers to be a contributing factor. That's 5.0mm of spacer but made up of three rings, means each can compress at different rates. If you'd had one spacer it would ...
Criggie's user avatar
  • 127k
2 votes

What's causing the clicking on my ProWheel MPX 11 crankset?

It really could be a lot of things. The first question is whether everything is greased that should be. This includes the spindle contact surfaces, the crank splines/lobes, the crank bolt, the bottom ...
Nathan Knutson's user avatar
2 votes
Accepted

Bottom bracket for 1991 raleigh classic man

You have specified the shell width as 70mm. This is a problem on the Raleigh bikes, which as far as I know, never use an Italian threading (which is also a 70mm width). A normal British bottom bracket ...
Noise's user avatar
  • 14.4k
2 votes

Are 68mm and 73mm bottom bracket left side cups identical?

The cups without a lip are interchangeable on the non drive side. If you use a 68 cup on a 73, you risk the lip bottoming out on the frame (in some circumstances) before the intended contact is made ...
Noise's user avatar
  • 14.4k
2 votes
Accepted

FSA Mega Exo 24 threaded shell BB turns free when off the bike, but turns rough and gritty once installed

I asked in comments if the bearing felt notchy when you turned it off the bike. You indicated in an update that this was true. Consider all the physical aspects of the bottom bracket: how wide the BB ...
Weiwen Ng's user avatar
  • 32.9k
2 votes

Heavy corrosion of the bottom bracket shell, but rest of the frame is fine

Many bike frames have a vent/drain hole in the bottom of the BB. Drilling one is a good idea. There are also normally small vent holes on the inside of the chain and seat stays too, more for ...
Criggie's user avatar
  • 127k
1 vote
Accepted

What is the difference between Shimano SM-BBR60 and Shimano BB-MT501

Road Shimano BBs require a 68mm BSA shell, and are mounted directly on the shell. MTB Shimano BBs require a 73mm BSA shell, and always require a 2.5mm spacer on the drive-side. The external part of ...
Rеnаud's user avatar
  • 21k
1 vote

What is the difference between Shimano SM-BBR60 and Shimano BB-MT501

They don't do the same thing and are not interchangeable. MT501 is a mountain BB. BBR60 is road. Hollowtech 2 road and mountain BBs made by Shimano are two separate systems that don't interchange, ...
Nathan Knutson's user avatar
1 vote

2018 Diamondback bottom bracket size

A couple things to start. First, are you looking to replace the bottom bracket and keep the same crank set? This is significant because the crank set choice largely guides the bottom bracket type and ...
Jeff's user avatar
  • 10.8k
1 vote
Accepted

Crankset specs for 2013 gt backwoods sport

Should be fine to install the new one - the crank/spider is secured to the bottom bracket spindle by the square taper. The marks you're seeing would prevent the cranks from rotating if they meshed ...
Criggie's user avatar
  • 127k
1 vote

What's causing the clicking on my ProWheel MPX 11 crankset?

The last time I had clicking I swapped out the BB and the clicking persisted and it turned out it was comming from the rear wheel quick release, I took wheel out and reseated it in dropouts and ...
Eddie Gauld's user avatar

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