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Sealed Shimano Hubs and Bottom Brackets - Service Life?(3 posts)

Sealed Shimano Hubs and Bottom Brackets - Service Life?Fez
Jun 5, 2003 9:51 AM
Re: Sealed Shimano Dura Ace hubs and Shimano Ultegra bottom brackets

How long can these things go? Do they slowly get less efficient due to increased resistance from bearing, seal and grease breakdown?

Should I consider replacing at regular mileage intervals (like 10,000?) or should I run them indefinitely as long as there is no play or noises coming from them.

Last bike had 8,000 miles w/ no problems. Current bike has almost as many miles w/ no problms. Ride on mainly clean and dry roads.

Was wondering mainly if pedaling and rolling efficiency is uniform throughout the service life or if it progressively worsens, making replacement at 10,000 mile intervals worthwhile even if they still function OK.
re: Sealed Shimano Hubs and Bottom Brackets - Service Life?Jervis
Jun 5, 2003 9:19 PM
I don't know if I'd worry about it, as long as it rolls nice and has no play i'd say you're scott free. I have an 8 year old XTR on my mountain bike that grinds a bit but has no play at all and it adds less resistance than a new bottom bracket. So I say as long as there is no play and you don't feel like you're pedaling uphill all the time due to resistance, keep the thing on there, that's just 30 bucks less you'll have to spend.

re: time, not milescyclopathic
Jun 6, 2003 8:58 AM
grease tends to dry out.

Since BB uses cartrige bearings no maintenance, keep 'till death. Death means either spindel feels loose or increased resistance. Depend on mileage I'd say 5-10years is a good guess.

With hubs expect to repack and adjust once in two years (some do every year) and replace bearings and maybe cups (~5$ in LBS) every ~20,000mi or so. You don't realy have to repack hubs that often, but running 'em dry reduces lifespan.

Rolling efficiency is more or less constant. It goes up after initial break in and after repacks, and if shoots way up if bearings rust, grease dries out (bike haven't been used for several years), or cups wore out and hub is too loose. Do not replace unless there's a reason good luck