BB30 Aggravation

[zamboni]

Looking for a solution to a BB30 problem.

Purchased a new high level carbon fiber frame (brand unimportant at this point) with a cf BB30 shell. New FSA K Force Light cranks and bearings installed by race mechanic. So far so good. After about 1000 miles noticed play in cranks. Same mechanic removed cranks and bearings were able to be removed with finger pressure. Play in crank assembly obviously from "loose fit" between bearing set and bb shell.

If this frame had an alloy BB shell, Locktite 640 could be used but since the interface is the carbon fiber shell to the steel races, Locktite cannot be used since it would degrade the cf.

Even if the bb shell's inside diameter is out of spec, is there any remedy?

Waiting to hear from manufacturer.

Any ideas? Thanks.

 

[Greyhound Velo]

I've used sleeve compound (green Locktite, but I forget the number) to cure chronic creaking in BB30 bearings, but only as a last resort. If the cups in the frame are out of spec, there's really nothing else you can do other than replace the frame (which should be a warranty issue and not cost you anything other than shipping the frame back, check with the IBD that sold you the bike).

I honestly can't stand BB30, I think it's a bad solution to a problem that didn't exist, the only positive about it being slightly less weight and stiffer feel due to the large diameter spindle (both of which could be solved in other ways). In my shop we have had nothing but problems with BB30 bikes because the manufacturers don't use close enough tolerances when milling out the cups and the bearings themselves are not up to the kind of torque and wear that a bottom bracket has to withstand. The ball bearings within the cartridges are just too small and don't last long enough, the seals are either inadequate to prevent excessive seal drag, or cause too much friction if they are actually useful as seals, and the cartridges are too narrow to resist the side load that an adult cyclist puts on them in high power output situations.

The short version is that BB30 is crap, I wouldn't own a bike with that type of BB if you gave it to me free. They don't ALL suck, but the percentage that do is way too high to roll the dice on one. Definitely check with the shop where you bought the bike though, they should be willing to work with you on either fixing or replacing it.

Back to work to replace another Cannondale BB30 bearing set.

 

[dse1969]

It sounds like it's time for the frame manufacturer to send you a new frame. I'm on my third fame with a BB30 bottom bracket and haven't seen that problem. I would guess that your frame is a high end frame & fairly new thus should be under warrantee. Push hard for a new one!

By the way, I love the BB30 for exactly the reasons quoted above - it's lighter & stiffer. Agreed it needs a bit more maintanence & I probably replace the brarings a bit more frequently than a standard BB, but I see that as a small price to pay.

 

[Motomatt]

I too love the BB30 it's lighter & stiffer, and I have had no issues with maintenance on 2 different bikes each with more than 6 yrs of very hard abuse.

 

[BroDeal]

BB flex? Yeah...

I could switch to a BB spindle made of solid latinum pressed kryponite mined from antarctic meteorites with a max flex of absolutely 0.00000%, and I would not be able to tell the difference between that and my current BB spindle because I cannot feel any flex in what I currently have. The flex of pedal spindles has to be considerablly more, probably by an order of magnitude, than any BB flex. Add in crank arm flex and BB flex sounds like nothing more than a typical cycling marketing scam.

 

[Bustedknuckle]

BB flex? Yeah...

I could switch to a BB spindle made of solid latinum pressed kryponite mined from antarctic meteorites with a max flex of absolutely 0.00000%, and I would not be able to tell the difference between that and my current BB spindle because I cannot feel any flex in what I currently have. The flex of pedal spindles has to be considerablly more, probably by an order of magnitude, than any BB flex. Add in crank arm flex and BB flex sounds like nothing more than a typical cycling marketing scam.

Reality, what a concept.

 

[Bustedknuckle]

Looking for a solution to a BB30 problem.

Purchased a new high level carbon fiber frame (brand unimportant at this point) with a cf BB30 shell. New FSA K Force Light cranks and bearings installed by race mechanic. So far so good. After about 1000 miles noticed play in cranks. Same mechanic removed cranks and bearings were able to be removed with finger pressure. Play in crank assembly obviously from "loose fit" between bearing set and bb shell.

If this frame had an alloy BB shell, Locktite 640 could be used but since the interface is the carbon fiber shell to the steel races, Locktite cannot be used since it would degrade the cf.

Even if the bb shell's inside diameter is out of spec, is there any remedy?

Waiting to hear from manufacturer.

Any ideas? Thanks.

Yep, those bearings need to be pressed in ala a headset cup-type press in. If they just fall in and out, the frame is made poorly and needs to be replaced.

Too bad but not unusual. just cuz it's a 'highend' frame doesn't mean it was made well.

 

[Black Dog]

BB flex? Yeah...

I could switch to a BB spindle made of solid latinum pressed kryponite mined from antarctic meteorites with a max flex of absolutely 0.00000%, and I would not be able to tell the difference between that and my current BB spindle because I cannot feel any flex in what I currently have. The flex of pedal spindles has to be considerablly more, probably by an order of magnitude, than any BB flex. Add in crank arm flex and BB flex sounds like nothing more than a typical cycling marketing scam.

So very true. I can see that you have yet to drink the Kool-Aid!! Everyone parrots marketing BS without having ever seen a lick of evidence to back their claims.