Removing BB90 Bearings with inner plastic sleave

jj911c2

I picked up the Park Tools BBT-90.3 tool to remove the bottom bracket bearings out of a Trek fitted with BB90. The problem I am having is there is a plastic sleeve (I believe for dust prevention) that runs between the two bearings. It fits tightly against the back of the bearings which makes the park tool unable to expand and get purchase on the bearings for removal.

Does anyone have tips for removing these bearings?

bbrap

Normally you can push the sleeve to one side slightly with a screwdriver or suchlike. Then use the tool slightly off centre to get the bearing moving. Then move the sleeve the other way and use off centre by 180 degrees. After a couple of goes the bearing should pop out. The other bearing is easy as the tool can be used as designed once the sleeve is out of the way. Hope this makes sense. I know the idea of the tool is to keep things square, but in this instance you have to skew it slightly.

hambini

The way I have gone about these is to knock the bearing out first by tapping on the inner race. Once that's out you should be able to get the sleeve out and then do the other side.

jj911c2

Thanks for the help hambini and bbrap.

I was able to remove the bearings by using a screwdriver to get a 0.5MM gap between the back of the bearing and the plastic tube and carefully inserting the tool to align with the gap. I then used a socket to insert into the tool to force the prongs to expand further which gave enough purchase to pop out the bearings. The plastic tube is two pieces that connect in the middle but the outside portion actually sits behind the bearing which is why it was so hard to get any type of gap to insert the tool.

bikingeveryday

Knocking out the bearing with a screw driver runs the risk of damaging the carbon fiber by canting the bearing as it being removed. The better way is to use a bearing extractor such as this one from Wheels Manufacturing. http://wheelsmfg.com/presses-tools/bear ... actor.html

kiribatichris

Park Tool BBT-90.3 is designed to get around this problem and works well. I've had no issues using it and several different frames and bearings with the Shimano 'dust' sleeve. Unless absolutely necessary, don't re-use bearing that are press fit. THe process of removing almost always involves applying pressure to the inner race and runs the risk of marring either or both races in the process.

http://www.parktool.com/product/press-f ... t-bbt-90-3

bikingeveryday

24X37 (24MM) SEALED BEARING EXTRACTOR from http://wheelsmfg.com/presses-tools/bear ... ctors.html

Individual extractor for removing 2437 sealed bearing
Bearing ID: 24mm / OD: 37mm / Width: 7mm
Insert the extractor into the bearing, tighten one side with an Allen key, and the collet expands to grip the inside of the bearing Tap the extractor out with a punch