bb30 short bearing life

Chris65

I have a Cannondale six which has a BB30 bottom bracket.
Last year it started to knock. The LBS fixed this by applying some Locktight which seemed to work for all last summer.
The bike was stored for the winter. This year I brought it out and on its third run out the BB30 developed a knock/grinding. LBS diagnosed this as defective bearings - I agreed. These have now been replaced.
The bike has only done about 3000 miles.

Has anyone else had this problem of have I just been unluck

Monty Dog

Common problem with BB30 I'm afraid, both creaking and bearing durability, particularly if riding in the rain

nweststeyn

Yup... My BB30 creaks regularly. A clean up usually sorts it, but the bearings need changed regularly.

A little tip though - if you are changing your bearings, go to an industrial bearing supplier and buy a bunch (bearing code 6806-2RS). Massively money saving and I've had the same lifespan out of £30+ 'BB30' bearings as I have out of £5 generic 6806-2RS bearings.

father_jack

hopefully bb30 will be replaced by better design for winter use....not looking forward to replacing my winter bike axle setup with external.

sturmey

Father Jack wrote:

hopefully bb30 will be replaced by better design for winter use....not looking forward to replacing my winter bike axle setup with external.

Cartridge type Square taper b/bracket for me in winter. Keeps out the muck.

crankycrank

Or you could try these seals. http://www.enduroforkseals.com/id255.html (Scroll down to middle of the page). I have never used, or know of anyone else who has used these but for the price it seems worth a try.

billybiker

Chris, similar problem with my Trek, I started a post years ago which I've just updated. I think its just a poor design, well, a good design but doesn't last very long in the real world.

sungod

the problems with bb30 start if the bb shell and/or bearings are not accurately made and fitted, if loctite is needed then imho it's a sign that something is out of tolerance

problems are compounded if any required maintenance isn't done

i've got bb30 (cinelli frame, sram bearings), c. 11,000km, all weathers, rain, lots and lots of rain, some more rain, dust, freezing, baking, still smooth and silent - the bb shell is well made, the bearings installed correctly, and i follow sram's maintenance instructions - when i remember

jgsi

sungod wrote:

the problems with bb30 start if the bb shell and/or bearings are not accurately made and fitted, if loctite is needed then imho it's a sign that something is out of tolerance

problems are compounded if any required maintenance isn't done

i've got bb30 (cinelli frame, sram bearings), c. 11,000km, all weathers, rain, lots and lots of rain, some more rain, dust, freezing, baking, still smooth and silent - the bb shell is well made, the bearings installed correctly, and i follow sram's maintenance instructions - when i remember

I have not had any issue with my BB30 on Synapse.. but I havent 'maintained' it for ages.. since exploring how to dismantle and put back ages ago... can you give us a rundown on the SRAM maintenance routine for me please,
ta

sungod

on mine, sram recommend greasing bearings every 100 hours riding or after a dunking, that's pretty frequent, i think it's assuming some serious abuse

anyway, 100 hours is too often for me, i probably do it around 2-3 times a year, this seems enough as there's still clean grease on them when i look

once i took the bearings out and did a full degrease/regrease, just for the hell of it, but the other times i just did this...

remove crankset, clean it

get some paper towel into the bb cavity and wipe out any dirt/grease/water/whatever

remove the outer shields, finger job

wipe everything clean with a cloth

using a fine pick, *carefully* remove the outer bearing seal

wipe everything clean with a cloth, again

use the recommended grease - sram says that is skf lghp 2, blue stuff, a 0.4 litre pack is about 15 quid, i use it for all bike bits that need grease

i put the grease in a syringe and pump it into the bearings

smear some on the seal, refit seal so that the excess grease squishes out *

put plenty of grease on the exposed faces, push on the outer shields, again the grease squishes out *

give it all a wipe

do the same on the other side

refit cranks and adjust preload

done

* there are two schools of thought: one says to apply less grease as there'll be a bit less drag; the other says pack it in, what harm's a teeny bit of drag vs. the potential for water/crud washing in; i'm of the latter persuasion, i ride all weathers, plus the higher fill means i can go longer before regrease

fwiw if i flip the cranks by hand, they spin freely 4-5 times, so there's not that much drag

there's an fsa video that includes bearing cover removal and cleaning/greasing here...

http://www.youtube.com/watch?v=9uQoas_f4Is

and the matching document...

http://webstore.fullspeedahead.com/downloadfly.aspx?download=downloads/Ceramic+BB+Maintenance+Schedule.pdf

nweststeyn

On the schools of grease-related thoughts discussion:

Using too much grease can mean more sticky surface area for dust and grit to stick to. Over time this will turn your grease into a grinding paste and just adds to your troubles, as I've found from experience.

jgsi

Thanks for that.. when it comes to new bearings which are cheap enough, whats the thoughts on the cheap bearing installation tool (FSA) as opposed to more expensive Park Tool one?
The former easier for a cok up I would have thought?

sungod

nweststeyn wrote:

On the schools of grease-related thoughts discussion:

Using too much grease can mean more sticky surface area for dust and grit to stick to. Over time this will turn your grease into a grinding paste and just adds to your troubles, as I've found from experience.

in this instance that's not correct, consider...

the grease is inside, totally filling the cavity, presenting minimum surface area, and preventing ingress of water carrying dirt

if i used less grease, there would be voids, which will increase surface area exposed, allowing dirty water into the bearing cavity where it would mix with the grease causing increased wear

...which is why fsa's engineer recommends more grease for harsher conditions

Herbsman

Use a normal BB with a BB30 adaptor. Problem solved

nweststeyn

sungod wrote:

nweststeyn wrote:

On the schools of grease-related thoughts discussion:

Using too much grease can mean more sticky surface area for dust and grit to stick to. Over time this will turn your grease into a grinding paste and just adds to your troubles, as I've found from experience.

in this instance that's not correct, consider...

the grease is inside, totally filling the cavity, presenting minimum surface area, and preventing ingress of water carrying dirt

if i used less grease, there would be voids, which will increase surface area exposed, allowing dirty water into the bearing cavity where it would mix with the grease causing increased wear

...which is why fsa's engineer recommends more grease for harsher conditions

Ahh yes, but the way I read the original post I thought you meant not wiping the excess grease away on the outside of the bearings/covers. I've seen loads of people leave excess grease oozing out of the outside of the BB inbetween the crank arm and frame, and this stuff gets filthy. I always use plenty of grease on the inside though.