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Bottom bracket squeek
NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.
As i'm sure its been done to death my bike is getting a few years old now and theres a little squeek under hard pedalling from the bb. I took out my cranks and there was plenty of grease and everything looked ok but i noticed the two bearings, while still running smooth, i could feel notchiness on them but not grabbing if that makes any sense? Its a Pressfit bb30 for reference.
Does that sound correct or could that be my squeek?
Thanks in advanced.
Jono.
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Hi Jono. When did you last grease your seat post? I was convinced at one stage that my BB was the source of a worrying squeak, but some research suggested I try cleaning and greasing the seat post and post hole. A good wipe down, shake out some sand and grit then lashings of Teflon grease and noise gone.
Makes sense as the seat will move in synch with your pedal stroke while seated so it's very hard to differentiate between a BB noise and seat post noise while riding. Does your noise occur with you standing while pedalling? With no weight on the seat the post, in theory, shouldn't move and therefore, shouldn't make a noise. Even if you eliminate the seat post as the source of the noise it probably wouldn't hurt to grease it if it hasn't been done in a while.
Hi Jono, u may ask someone to hold your bike next to a wall. Move around your seat with or without pedaling, on a trainer without touching if possible. I think you may be able which one makes noise. Hope help.
Also check you chainring bolts. That's what it was for me.
If the bearings are notchy, replace your BB pronto.
I just picked up a used set of Rotor cranks for the roadie with a power meter, and where the BB30 bearing ran on the shaft it has worn a groove in the alloy on the drive side where the bearing has obviously failed on the previous owner's watch. Fortunately that won't affect me as I'll be using rotor's BSA30 system to mount it, but I'd be seriously annoyed if that had happened to my bike.
As to solving the creak, it's a process of elimination.
Does it only happen seated? Saddle rail sockets are a common one I've found across several bikes. A drop of chain lube allowed to soak in with the bike upside down resolved it for the best part of a year.
I took my bike past the lbs and they said that it is advisable to change them as they are due but they had seen bearings in much worse shape. They also said i must change all my pivot bearings which is quite a hefty sum of money
I bought my bike new in 2011. Does 4 years sound like a reasonable service life for the bb bearings and pivot bearings?
Also how hard is it to do myself?
Also thanks for all the suggestions on locating the noise, definatly worth a go.
4 is reasonable, although I've got a 10yo Jekyll that is still perfectly fine... but it has far fewer bearings.
It all depends on how careful you have been to keep the high pressure spray away from your bearings.
DIY is doable with care and the right tools.
Problem is he didn't actually look at the bearings, he just assumed.. so i'm not convinced especially as i'm really careful and a take care of my bike.
The bb on the other hand is a different matter that is defiantly due. Ive got a pf30 bb does that mean i need to buy bearings in cups or can i buy bearings buy themselves? I understand with bb/pf 30 the bearings seat on the frame and form the bottom bracket but i'm still unsure what i need to be buying
My understanding of PF30 is that the plastic cups the bearings sit in don't usually survive the removal process. BB30 the bearings sit directly in the frame with no plastic cups,so bearings only is feasible but greater care is required in installation and removal, especially if the frame is CF.
Best to buy the full kit rather than just the bearings from a bearing shop.
Installing should be straightforward and the bearing press is comparatively cheap. Or you could make your own with a long enough bolt and some scrap metal pieces.
Yeah i wasn't sure if the cups were sacrificial so to speak. Can anyone recommend a good pf30 bb?
Also is it worth doing it myself or should i leave it to the professionals? It dosen't look to hard a job, just not sure if its worth the investment in tools and how much usage i will get out of the tools.
go the same manufacturer as your cranks, but the top level. EG, if SRAM X7, go XX. I'd stay away from ceramic bearings, though. Lots of money for no better performance.
Unless it's FSA. Then you're possibly screwed. Their BBs are junk.
Good news i'm not fsa then. Im running sram carbon cranks. I cant seem to find much other then this sorta thing http://r2-bike.com/bilder/produkte/gross/Truvati... for sale, there isint much range in pf30 from what i see.
I know its nice to do stuff yourself and learn from it, but this is a good example of a time where taking it to a bike shop, and asking if you can watch them do the job would be valuable.
Knocking out a PF30 BB can be super easy, it can also be a nightmare.
Putting a new one back in straight is pretty important, and although you *could* make a tool or buy one, and do it yourself, its easy to get it not quite right - and thats when bearing run rough, wear quickly, and make noises.
I am all for learning - but its best done by watching a pro doing it, and asking questions etc. Their use of tools, carbon paste, little tricks will be great for you to see first hand. Then maybe next time you give it a go yourself.
Just my thoughts anyway.
4 years on a single BB? Holy smokes. I do one a year - and thats assuming I havent been riding in the filth. Then it would be 2 / year.
e.g. a bb can be destroyed in just one race (Husky, Cap Pun a few years back, Cape to Cape on the beach...) so even if you do avoid really foul weather, they take a beating..
Jonathan (and those who don't know), CBD offer free maintainence courses first wednesday of every month.
More info here: http://citybikedepot.com.au/info/educate
So my bike isn't ripping me off
by the time i've bought the tools and stuff it isn't worth me doing it. Especially associated with the pain and anguish of me doing the job correctly and not being sure if its right or not.
As for the maintenance its only free if i bought my bike from cbd. Otherwise $60.00 i saw?
Still not a bad idea..
Thanks,
Jono.
I'd drop the pressure or preload on your shock, unbolt it and then check that the swing arm and linkages move smoothly and freely.
Also twist the swing arm left and right. A bit of deflection may be normal but it shouldn't slop around at bearings.
If this is okay I'd suggest all is good. Also check the torque on the linkage/swing arm bolts but beware as from what I've heard most bearing damage comes from owners over tightening them.
My old Enduro for example copped a beating for 5 years hucking off stuff and never had bearing issues other than the BB. A mates Demo he lovingly tightened every week had stuffed bearings in back end quickly.
Identical to the PRO one I have
http://www.torpedo7.com.au/products/T7TOWN0WS/ti...
They actually do 2-10Nm.
Edit: 2-20Nm
Ive never touched the pivot bearings so hopefully there ok but very good tip with lower the pressure and checking defiantly worth a go. Its ironic how in a lot of cases care and attention hinder. At one point i was taking my chain, cassette, and cranks off after every ride and servicing but now i only do it every half dozen and take my chain off and clean it every ride, i guess after 4 years im only due for a chain now so its working
Ive already got a 3/8 torque wrench which is 6.8nm at its lowest setting which im assuming is probably ok for tightening bearings as 6.8 is not very tight at all.
Some bikes have the torque written next to the bearing, otherwise download a manual for the bike and it should be in there.
Sounds like one clean bike! Unfortunately I have a different approach at moment. Found that if you do home renovation and don't ride your bike then it doesn't wear out! Saving heaps...
Nearly done and back riding soon! Only been out 9 times since November. Celebrating reno's finishing by going to Whistler September 5th!
I had a similar squeak with my CX bike. Just over 12 months old and the annoying squeak.
Did the seat post, seat, lube all the bolts etc. Checked the crank bolts etc. Even looked at the cables to see if they were the issue.
The shop had the bike for a few days to check over all other options, and in the end the BB was the issue. Not much to feel when moving it in your hands (and it was less than 12 months old), but when it was replaced all good.
The real issue was what version of BB30 (I understand there are about 3) was in the frame. In the end the shop ordered the wrong one and I had to wait a few extra days to get the bike back. If I had ordered the BB myself and done the same thing (wrong version) I would have been up for another BB and a bike in bits for another week.
Sometimes if you not sure get the shop to do the work and they can sent the wrong bits back or keep them and you don't get charged.
It's wise to get a torque wrench that can do the light stuff. Quite a few fittings on the bike are 5Nm or less, especially if you have carbon bling bling.
I use mine far more often than I would a 5.8Nm+. That said, I'm in need of one right now that will do up to 50Nm so I can fit my new power meter cranks.
Four years from BB bearings, that is awesome!
I used to do two FSA ISIS BBs a year, Ex type would go for a year. Due to my current setup being silly and my BB shell is an egg I get three to four months from my BB92 bearings.
I envy you people.
Alrighty, so i sent it into the shop, she should be spot on when i get her back. Thanks for the help everyone. Also getting a few other niggles sorted out. Looking forward to many more bb's!!
Cheers.
I should go and check whats been growing in mine!
I chased a squeak for months that I assumed to be in the suspension. It turned out to be the sprocket nut not tight enough. Hope the LBS does its job right.
I picked up my bike today but haven't ridden it, as soon as i went outside with my bike it started pouring
according to the mechanic he says that the bb would of been the noise i was hearing. I also did full cables inc my dropper post so everything is now silky smooth (hopefully).
All i need are clear skies and a trip to ourimbah now and the equation will balance
Thanks for the help everyone.