Monday, November 26, 2007

Q&A: Hub cleaning and repacking

QUESTION:
I have just purchased a new set of wheels for one of my road bikes. They are
built on Shimano Ultegra hubs. I ride this bike 6,000 mile/year on clean,
dry and smooth roads. I'm a do-it-yourself mechanic and would like to know
from an expert how many miles I should expect to ride before I clean and
repack these hubs.

Thanks,
Rob

ANSWER:
Thanks for the email, Rob. Hubs should be cleaned and repacked with fresh
grease about once a year. If you get stuck in a bad rain storm and have to
ride in it for hours, you should check them afterwards by removing the
wheels and turning the axles in your fingers and feeling for grittiness when
you turn them. If they're still silky smooth, there's no need to do
anything. But, if they got gritty from all that rain riding, it would be
good to dismantle them, clean them and regrease them.

But, if you are lucky enough to ride on dry, smooth, clean roads for all the
6,000 miles, once a year will be fine. And, when you take them apart the
first time if you find that the grease is clean and fully packed, covering
all the bearings, that's a great sign that you can repack the hubs even less
often. So, you could bump the interval up to every 18 months and try that.

Jim

No comments: