Bearing outer race extraction - Please help !

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Bearing outer race extraction - Please help !
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Posted: Jun 22, 2019 at 9:11 Quote
Trying to remove the outer race of a main pivot bearing on a demo 8 frame. The bearing pushes into a ridge on the inside of the frame shell.

It cannot be smacked out with a screwdriver because of the frame ridge inside. The bearing size is 50x62x6.

Any help is appreciated


Posted: Jun 22, 2019 at 11:37 Quote
Flathead Screwdriver through from the other side on the lip of the bearing your pointing at in the pic, tap gently should pop out.

Posted: Jun 23, 2019 at 2:03 Quote
Can you get a screwdriver in behind the race from that side between the race and the support shoulder? If so, I'd heat the housing up and you should be able to pry it out (a wee butane torch would be ideal)

Posted: Jun 23, 2019 at 13:38 Quote
Going to have a look at it again tomorrow. i didnt notice at first. but you both might be right and it might be possible to tap it from the inside. Unless im looking at it wrong there seems to be a potential place to put a screwdriver on the left and right side of the bearing.

Either the frame ridge is the same diameter as the bearing outer or its just there so you cant push the bearing in too far.
(Or maybe the bearing was just so worn down it's ovalised like that at the bottom)

There is however that dip in the middle of the race where the bearings would have been. Might be able to use that to tap it out ? or at least try to wedge something in there and try to push or pull it out..

Posted: Jun 23, 2019 at 14:01 Quote
Where you have labelled main pivot bearing, the tip of that arrow is a slight lip put flat head in there from the other side it will be on an angle but tap the top of the screwdriver and it will come out. Might have to move the screwdriver around the lip a few times but it will pop out eventually. Shouldn’t really need heat.

Posted: Jun 23, 2019 at 14:38 Quote
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F372632788143
Have a look at that might help, I've got one to take the bearings out my status frame

Posted: Jun 24, 2019 at 8:25 Quote
Just thought i would update you guys ! Smile
So i attemped the bearing lip method as suggested, but the screwdriver kept slipping and its not actually as deep of a groove as it looks in the photo.

But i've noticed from the other side, 1 part of it is slightly higher than the frame ridge. so im gonna attack it from there tomorrow.

So i decided to get the other (Not really broken but isn't smooth moving) one out instead. They really get stuck in there don't they Eek , However after about 20 minutes of high anxiety stress and selective tapping. It popped out ! tup

As you can also see in this photo is the slight lip of the other bearing where i intend to smack it out from. hopefully it will come out eventually. When you get about half way out, it's only a couple of smack's before it pop's.

Also i look'd at your bearing extractor tool. but unfortunatly it only seem's to fit upto bb30 size bearings. Unless you can get other adaptors for it ?

Posted: Jun 25, 2019 at 4:36 Quote
Progress update lol - Managed to smack it out a bit more. 1 side is now flush with the frame. Just gotta keep at it huh. Eek

Posted: Jun 25, 2019 at 12:08 Quote
Why did you dismantle the bearing with the outer race still fitted to the frame? In situations like this, you need to remove the whole bearing in one piece by applying pressure or impact to the inner bearing race from the opposite side. Still having the inner race attached gives you the surface area to hit or press against. I don't know this exact frame so I apologise if there is a disassembly process that requires you to break the actual bearing up the way you have.

Posted: Jun 25, 2019 at 12:13 Quote
Spangoolies wrote:
Why did you dismantle the bearing with the outer race still fitted to the frame? In situations like this, you need to remove the whole bearing in one piece by applying pressure or impact to the inner bearing race from the opposite side. Still having the inner race attached gives you the surface area to hit or press against. I don't know this exact frame so I apologise if there is a disassembly process that requires you to break the actual bearing up the way you have.

LOL... I thought the same thing. I will give the OP the benefit of the doubt and assume it broke off in there.

OP: when tapping it out, tap around the entire circumference, not just at one point. otherwise the bearing will bind and not come out. You can also spray some penetrating oil in there to help things move.

Posted: Jun 25, 2019 at 12:23 Quote
cmcrawfo wrote:
Spangoolies wrote:
Why did you dismantle the bearing with the outer race still fitted to the frame? In situations like this, you need to remove the whole bearing in one piece by applying pressure or impact to the inner bearing race from the opposite side. Still having the inner race attached gives you the surface area to hit or press against. I don't know this exact frame so I apologise if there is a disassembly process that requires you to break the actual bearing up the way you have.

LOL... I thought the same thing. I will give the OP the benefit of the doubt and assume it broke off in there.

OP: when tapping it out, tap around the entire circumference, not just at one point. otherwise the bearing will bind and not come out. You can also spray some penetrating oil in there to help things move.
Good point, didn't think that the bearing might have been really fooked that it broke up on disassembly. Hopefully the OP can clear that one up

Posted: Jun 25, 2019 at 13:37 Quote
Using an actual punch tool helps a lot, screwdriver tip is too soft.

Posted: Jun 26, 2019 at 1:55 Quote
I didn't remove the inner race that's how it broke !. The non-drive side bearing was intact and was easy to tap out.

I've just sprayed some wd40 around the edge. Punch tool is too big. It was literally like 1mm that was sticking out enough to even be able to start the process.

Full story of what happened
1.Started hearing crack sound coming from somewhere on the frame
2.Checked over headset etc.. couldn't determine
3.Checked the bottom bracket shell/bearings. All looked fine
4.Kept on riding because nothing looked broken.. but kept getting a click/crack sound. So check over the bike completely
5.Started washing the bike and noticed a bit of metal poking out of the bb area wedged between the frame and the pivot arm
6.Removed the bb shell, lifted the rear triangle and 2 spacers fell off and then i saw the drive side bearing had no bearings in it !! and the inner race was free floating Eek

Which lead's upto now, which is trying to remove the outer race.

What i think happened - The bit of metal that was poking out is actually the bearing seal. They are metal and so when it broke it must have damaged the bearing cage and they all fell out at some point.

Posted: Jun 26, 2019 at 2:38 Quote
Thanks for clearing that up, lucky it didn't do more damage. If all else fails, a last resort would be to cut away at it with a dremmel or drill. You would have to be super careful not to cut into the frame. I removed a bearing race on my cars diff that way, cut a groove most of the way through the race but allowed enough so I didn't cut into the diff but enough that I could break the rest of the cut with a screwdriver. Good luck

Posted: Jun 26, 2019 at 4:18 Quote
Sorry if that sounded aggressive.
Yes dremel was definatly a consideration. I've just made some progress tho (Think the paint was holding it in as well lol)

Thank's for all your advice. It's just akward because they decided to design this frame so the pivot is part of the chainstay. so the bearing's are bigger than usual. Otherwise a standard bearing extractor/press would of done this by now Really Mad

I've been gently tapping all the way around. It should be out by tomorrow lol

(The part with the arrow was stuck in the frame yesterday)

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