Author Topic: Bottom Bracket Removal Advice? - Threaded/Press Fit  (Read 1681 times)

patliean1

Bottom Bracket Removal Advice? - Threaded/Press Fit
« on: March 04, 2025, 02:18:28 PM »
Hey yall,

I have a BB86 press fit bottom bracket I want to remove. One side presses in, while the other cup threads in. This makes for easy install but terrible removal.

Once I remove the threaded side first, my existing tool isn't long enough to "push" the other cup out. That and the inside bearing "lip" isn't pronounced enough for my bearing removal tool to remove the entire cup without removing just the bearing cartridge itself. Leaving behind just the shell.

I was thinking of making a round wooden block where I could use a rubber mallet to knock the bearing/cup/shell out.

Any thoughts?



glepore

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #1 on: March 04, 2025, 03:32:02 PM »
That would work, but its unlikely that you could, without say a lathe, make a round tube of exactly the od of the bb shell and thus make contact completely around the cup. A square piece of wood would be as effective as a round piece that wasn't perfect, just go slow at various places on the cup, rotating with each tap.
Are you planning on reusing the bb? If so, why not leave the cup in place and just press in new bearings?

It might help to know what bb is in there, but if you're going to replace everything I have an idea, but it would destroy the shell.


bremerradkurier

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #2 on: March 04, 2025, 03:58:28 PM »
A piece of PVC pipe with OD close to the cup diameter might work better than a wooden block.

patliean1

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #3 on: March 04, 2025, 05:07:11 PM »
This is the bottom bracket below. I'm using the BB for another frame

https://novatoride.com/en/products/boitier-de-pedalier-bb86-shimano

glepore

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #4 on: March 04, 2025, 09:43:37 PM »
Ok. My first impulse would be to get a large flat washer that is close to the ID of the frame's bb area-put it on a threaded rod with a nut on either side and use that as a tool -just tap on the other end of the rod with a hammer. The pipe idea is ok as well, as would be a square piece of wood. Honestly if its not bonded, you could even try a large screwdriver alternating taps left and right side very cautiously until it moves. If its bonded with Loctite you'll need something that maybe catches the sleeve part in several areas, the washer method is most likely to do that. If its a little small, don't try to center it, use it bottom, tap, then top, tap. It'll likely engage enough of the lip to move it without an issue.

Edit-looking at the installation manual it appears there is a fairly nice size step between the threaded sleeve and the cup, so finding a washer that mostly or totally engages the sleeve but fits in the frame shouldn't be hard.
« Last Edit: March 04, 2025, 09:52:07 PM by glepore »

glepore

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #5 on: March 04, 2025, 09:46:36 PM »
Gotta say, that's a wacky arrangement as no standard removal tool would work. Token's system (and others) that thread together with tool engagement on both cups is much easier to remove

Serge_K

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #6 on: March 04, 2025, 11:39:44 PM »
https://www.aliexpress.com/item/1005005896124123.html It's what i have. On the listing they mention the sizes of the oval things, hopefully one is the right size?
Before that, i managed to remove a really old PF BB from a my giant with a simpler BB tool (didn't have the oval thingies) and a 3d printed oval thingy & metal washers.

Fast on the flat. And nowhere else.

SirBikealot

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #7 on: March 05, 2025, 05:13:56 AM »
is the conection between drive side and non drive side solid? If so, i would unscrew the bb a few rotations and then tap it back in until the drive side pops out.

glepore

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #8 on: March 05, 2025, 07:41:05 AM »
is the conection between drive side and non drive side solid? If so, i would unscrew the bb a few rotations and then tap it back in until the drive side pops out.

Yes, that's a good idea as well.

patliean1

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #9 on: March 05, 2025, 08:19:32 AM »
is the conection between drive side and non drive side solid? If so, i would unscrew the bb a few rotations and then tap it back in until the drive side pops out.

I'm such a mess over here LoL. I tried this months ago on a different frame using the same BB, and ended up ruining the threads inside the shell. So now the BB is toast.

The problem is the inner sleeve/shell isn't removable on its own. I have the same tool as @Serge_K . Works very well for removing 3-piece pressfit cups, where you can remove the sleeve prior from either side. The silly threading rod isn't long enough, but it's clear I'm doing something wrong. Will try a flat washer as @glepore mentioned.

Thanks everyone for your help. I really appreciate it!

ZacItaly15

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #10 on: March 05, 2025, 09:08:20 AM »

patliean1

Re: Bottom Bracket Removal Advice? - Threaded/Press Fit
« Reply #11 on: March 05, 2025, 10:49:41 AM »
After an hour of dicking around with different washers and removal setups, I was able to get the bottom backet out.

Thanks everyone for your help.