Replace the bearings on a 68 * 122.5 sealed cartridge bottom bracket
 

Hi people,


I own a Decathlon BTWIN Rockrider 340 bike and it has done close to 2500kms. I recently heard creaking noises while pedaling and have decided to rebuild the bottom bracket.

These are the specifications, VP-BC73 sealed cartridge bottom bracket with a size of BC1.37" x 24T (68 x 122.5).

The bearings that have worn out are both a 9002RS and I see that these bearings are non standard, meaning I can't be able to find these at a bearings shop easily.

Also before I get there, I do not know how I can pull these bearings off the square taper spindle as the spacer thingy which is between stops me from placing a 3 prong bearings puller to pull it out.

Could anyone suggest any hack here? I will be doing this for the interim after which a replacement of the BB is certain, but I just want to be sure that I do the re-packing of the grease on both sides of the bearing before I put these back on the bike.


Thanks in advance.

You sure that's not a 6002 or 6902?

Standard procedure is to just throw the old BB bracket away and install a new unit like a UN300

https://www.jensonusa.com/Shimano-BB...SABEgKLpfD_BwE

Replace the whole thing, it's cheaper than the bearings alone.

Yes, I will be replacing the BB set itself as finding these bearings and doing the replacement is not worth the time. Plus lot of miles to munch on the highway and trails.

...not sure I understand the purpose of your question in the first post then ? Why do you need to pull and replace the bearings in your sealed unit, if you are going to replace it anyway ?

Well.. its just a few small rides that I intend to do with the existing setup, just to save money on a new BB set. Once I'm getting ready for a long ride, I'd replace it with a new set. I don't ride long normally, so commuting and a bit of city rides should be doable with rebuilt bearings.

Just replace the bottom bracket, there is no benefit to replacing bearings on a square taper bottom bracket unless they are loose ball and even then I would replace with a sealed cartridge unit. Commuting is some of the roughest riding your bike generally sees for most people, because you are trying to get from home to work and back and usually when you are tired or worn out or stressed or whatever and you get home and you probably don't want to to do maintenance and you may not do it often and sometimes at all. Get a decent quality BB and it will probably be only marginally more expensive than bearings but will end the hassle of having to press in and out those bearings with tools you may not have. The only square taper BB I might consider replacing bearings on is a Phil Wood unit and even then I would rather just have an SKF or IRD Defiant (QB-95) and just have something that lasts and lasts and lasts with easy install (Phil Woods are a little more fiddly not by much and they are very high quality) You shouldn't need to replace a bottom bracket super often unless you are buying cheap stuff or trying to rebuild them constantly.

Raghavcd100 :

I know you said the culprit is the B.B. bearings but creaking when pedalling can also be caused by loose chainring bolts - even one loose can do it. Might be worth checking for this as well.

You would be spending more money, not saving money, for “a few small rides.” :foo:

Yes, I have ordered a new BB set and will just replace the shot BB.

Now, this could be interesting, as i too had this hunch initially. Let me reconfirm if it has anything to do with the creaking. Thanks.

Yes, I am happy I had this discussion with you guys, I was only looking for an interim solution here till I get myself a new BB set, but looking at the cost of a brand new BB set, I feel too tempted to buy and replace rather than experiment with DIY hacks.