15 posts • Page 1 of 1
The new S5s and R3/5s use PressFit30 bottom brackets, which on a quick glance look to be too hard to replace or tinker with, with equipment being costly and prohibitive.
Ive recently had to replace my bottom bracket a few times, so i thought i would put up a quick guide on what to buy, and how to do it...
Theres alot of good info on the nuances of doing this job, or fixing creaking PF30 BBs over on the cervelo forum... so much of the credit for this needs to go to the guys over there....
Removal of PF30 BB Cups:
DO NOT BUY ANY OTHER TOOL BUT THIS!
http://www.parktool.com/product/bottom- ... 0-bbt-30-3
The important aspect of buying this removal tool from Park Tool as it comes with 2 bushings that allow u to make an inexpensive press out of some threaded rod.
Other tools required:
Loctite Primer 7649 (Primer N) and Loctite 609 (if you want to loctite the cups into the shell to reduce creaking)
Threaded rod/nuts/washes for pressing in new PF30 cups/bearings (as outlined below) - Cost: 5/8 threaded rod from Bunnings $7; 4 nuts & 2 large washes $3.
All is contained here in the following link. Ive added a couple of my own pics to show any idiot can do it. If you wish to loctite the cups in, spray the loctite N primer on the BB shell, put loctite 609 bearing retaining compound on the cups and press them in with your threaded rod and bushings
http://m.pinkbike.com/news/Tech-Tuesday ... -2012.html
Fantastic Dr Mutley. Thanks heaps, my bits are on the way
Here is a pictorial story of a mugs attempt at bbright bottom bracket replacement
The creak meister in all its glory, probably shivering in fear at the sight of me and tools in close proximity
about to have a go at the non-drive side bearing. I reckon the bike is really scared now. I was a bit anyway. Hoping the bloody things would come out easily enough.
about to do the drive side bearing
The bearings came out fairly easily with some firm taps with that dead blow hammer in the earlier photo.
You can see the new sram bearing has a nice rubber seal that the old fsa goer did not. Hopefully they will be creak free and will last a while
Loctite and alcohol wipes used to clean up the surfaces prior to installation
A couple of photos of the bearings installed courtesy of the Dr Mutley bbright bearing installer (patent pending)
The drive side bearing went in a bit tighter than the non drive side and was a bit noisy as it slowly seated itself. I tightened it up until the lips of both cups were flush with the frame. I managed to resist using my normal torque setting of strip the thread and then back it off half a turn
I'll leave the press insitu until tomorrow and then install the cranks again.
Many thanks to Dr Mutley the ACF Cervelo guru
left the bearing installer on for a couple of days as I've just had a couple of night shifts
Crank set back on today and success
Back to being a normal Cervelo- stiff,fast and silent
I'm glad the install went well, but have you given any thought to how you are going to remove the bearings next time? Usually when Loctite says "High strength" they mean it. High strength usually means can't be removed with hand tools. I'm intrigued by this and hope someone has a good answer. I know I'm not the biggest fan of either carbon or press fit (too pragmatic for either) but I still hope a solution is available. Has anyone done this process twice yet?
I asked the question on the cervelo forum and some have but yes well spotted that bit is a bit scary.
There's always the risk of it getting run over by the car if it won't come out I guess.
It should be fine. I've removed loctite'd cups before and they come just as easy as the non-loctited ones. The loctite is just a gap filler that keeps the cup from rotating in the shell. One thing you can do though to ease the removal is to warm up the loctite with a hair dryer prior to removal. This will soften up the loctite. DON'T use anything hotter than that that though as you might damage the finish on your frame. Make sure to clean off all the old stuff before installing the new. Good Luck!
I've removed mine after being loctited in with 609 & primer, and they came out easily, without much more force with the hammer. So nothing to worry about there... Next time I take my BB out I'm just going to use some DuraAce grease to refit, and compare.
Threaded versions of the newer standards seems like a good idea to me. The press fit standards obviously aren't as trouble free in many cases. Fortunately for me, I can't see any major problem with 24mm steel spindles and standard external bearings.
I tend to agree, carbon press fit shells are obviously much lighter, but for the added hassle they sometimes can present, I much prefer my older threaded shells...
The external threaded cups are easier but don't don't allow the bottom bracket area of the frame to be physically as large. The S5 certainly is stiff and the large bottom bracket probably has a bit to do with it.
I managed to work out how to change external cups myself but couldn't have done these without several pm's from Dr Mutley.
Sorry, should have been more clear. What I meant was if you made standards like BBright and BB386 threaded instead of press fit, they would be more reliable. Having to be glue fitted rather than just press fitted is a failure on the part of manufacturer(s) and/or standard IMO.
How do you thread them in or out though? When the bearing is on the outside. Maybe some sort of pin tool or something. I'm no engineer, maybe there's a patent in there for you Nobody.
Edit: well that is one of my stupider posts. Derrrr maybe like the square taper bottom bracket was screwed in. FFS thanks for being polite to the idiot Nobody
I don't know of any regulars on these forums I'd class as idiots, just a few who act that way occasionally. You, however aren't one of them.
My point is if they can make a BSA to 30mm spindle adaptor, they can certainly make a press-fit frame shell a little larger and make the bearing shells screw (all the way) in instead. However, now the press-fit "horse has bolted", the manufacturers/designers are unlikely to go back to screw-in designs as they might add a few grams. Which makes me wonder where the weight-at-all-costs philosophy will lead the cycling industry for racing bikes next.
I would happily wear the extra 50 grams weight for the added convenience of a screw in bbright bb. If weight saving is the reason for press fit then that is weight weenyism gone mad. . Particularly when the bike has to weigh at least 6.8kg anyway
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