Bike Forums - View Single Post - Yet another BB30 creak thread......(sigh).....

03-30-15, 11:42 AM

#36

Campag4life

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Quote:

Originally Posted by loimpact

Crank is FSA-K Light (as mentioned in the OP)

And, no, I haven't gotten the memo about servicing crank. Once torqued properly (especially a crankset like that in a sealed-cartridge bearing) I can't imagine they'd need servicing. (Kind of like front wheel bearings on a modern vehicle, super-wazoo dust seals not withstanding)

Then on this I was definitely uninformed. Again, I know a great number of folks who don't even pull their chain in a year's time, much less headset or cranks. My headset maintenance, in fact, was only to troubleshoot another "tick/crick" that turned out to reside in the spacer stack anyway, thus never truly requiring anything be done.

I do ride in So Cal so we're fairly dry, with a rare ride in the rain a couple times per season, perhaps. Otherwise, again, with my knowledge of bearings as they exist in everything from hubs, discs, drums and CV's....I wouldn't have otherwise thought a "sealed" environment would need monthly or even semi- monthly servicing. (Maybe the bike industry should employ "bearing buddies" a la the boat trailer industry)

I will certainly pull the cranks and check 'em out. And if it even needs be said, I will do what I feel is necessary to ensure this is not something that necessarily needs to be revisited as often as perhaps some might think. Again, I truly don't think it should be so.

And also, thanks for coming up w/ the green loctite solution. I truly did search quite a bit & there are plenty of whacky solutions out there but if yours is the right one....then many thanks!! (It shouldn't required us folks to do that with the plethora of engineering available to folks like C'dale.

Thanks for the vote of confidence. And, yes, what I would have mentioned to Campag is that there is no "preload" per se as I liken "preload" to what we see in loose-bearing cup/cone applications and....again....wheel-type bearings found on modern vehicles. (If not the bike industry's headset assembly which requires a VERY finicky touch in preload)

Thanks again to all!!! Much good info!

P.S. To answer earlier about mileage.....Interestingly enough, I'm at about 9 months into this bike and almost exactly 3,000 miles.

Notice they are called dust and not water and grime seals. The dynamic is...with mileage, grease dissipates. Water and dirt aka abrasive slurry can fill the displacement of the grease lost. This increases bearing drag and wears the bearings out prematurely or can. BB30 bearings are cheap. Many who are knowledgable about bike maintenance for example will pull their crank off their bike every couple of months and pop the bearings out and replace them with new. Here is the drill. Buy a handful of sets of BB30 bearings. Every 2-4 months or 6 months at the most, pull the crank. You don't ride that many miles and you mention not in a lot of rain. Replace the bearings with new bearings. $7/ea for ABEC-5 quality BB30 bearings available at local bearing supplier. Don't throw away the old bearings. Repeat above for next 6 months. 20 minute job. After you have a couple of sets of used BB30 bearings on hand, pop the dust seals. Take a jeweler's screwdriver and they pop right off...held on with an interference fit. Soak bearings in kerosene or mineral spirts. Toothbrush the bearings on both sides. Spin and let dry. Same procedure for rollerblade bearings btw. Regrease with any common auto or household grease. I like Mobil 1 but use anything you like. More viscous grease will last longer but offer fractionally increased drag. Pop the dust covers back on. If you do this for a couple of repetitions for $25 you can get down the road 3-5 years. Can't beat that for a price of a BB. Just takes a little time. If you don't have a big screen in your garage or work area, get one.

HTH.
P.S. I didn't invent Loctite on bikes. Major bike companies like Specialized and Cannondale did in an effort to quiet BB30 customers complained about. I have worked with Loctite engineers however on auto related product development...a good company.

As to your preload...it may or may not be OK. The way to determine this and this is graduate level bike mechanics

is...you assemble the crank to the bike without a wave washer. You measure the gap on the spindle with calipers. Set your wave washer on a flat table on end. Measure its free standing height unloaded. Divide this value by 2. If the gap you measured with your calipers is much different than 1/2 the free standing height of the wave washer, you likely have too much or too little preload.

Last edited by Campag4life; 03-30-15 at 11:49 AM.

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