Cannot Get Stubborn Bottom Bracket Off

Hello everybody, I'm sure your day is going better than mine lol!

I'm trying to get my bottom bracket off my mountain bike. I have the replacement cartridge and the proper bottom bracket tool. Its an old Trek 830 that I'm rebuilding.

Here's what happened: I put the tool on the plastic cup side, wrenched it down and BAM I snapped all the splines off the plastic cub, ALL of them! From my understanding though I can still get the drive out, but tomorrow I plan to blow torch the plastic cup to dust. Any other ideas?

Then theres the drive side. First problem is, the tool slips, and I don't want to strip it. I'm turning the drive side to the right to loosen it, like it should. I was hammering on the wrench, and the thing doesn't budge, not even a little. I tried WD40 with little help.

How am I going to get this thing off?

look at the replacement unit and see how it's threaded, it may be threaded the opposite to normal

look at the replacement unit and see how it's threaded, it may be threaded the opposite to normal

rgnjc said:

I'm turning the drive side to the right to loosen it, like it should. I was hammering on the wrench, and the thing doesn't budge, not even a little. I tried WD40 with little help.

Are you sure you've got the right tool? It shouldn't slip. Older Shimano BB tools won't fit some newer BBs because the centre of the tool won't pass far enough over the inner centre of the axle. I had the same problem a couple of weeks ago and had to buy a new tool - the same as fits the Octalink BBs. It has a retaining bolt which screws into the axle to make sure it can't slip as you apply pressure.

Also, with the plastic cups, the last thing you want to be doing is 'wrenching down on' them. But I guess you already found that out for yourself... 😄

rgnjc said:

I'm turning the drive side to the right to loosen it, like it should. I was hammering on the wrench, and the thing doesn't budge, not even a little. I tried WD40 with little help.

Are you sure you've got the right tool? It shouldn't slip. Older Shimano BB tools won't fit some newer BBs because the centre of the tool won't pass far enough over the inner centre of the axle. I had the same problem a couple of weeks ago and had to buy a new tool - the same as fits the Octalink BBs. It has a retaining bolt which screws into the axle to make sure it can't slip as you apply pressure.

Also, with the plastic cups, the last thing you want to be doing is 'wrenching down on' them. But I guess you already found that out for yourself... 😄