Ask a Mechanic | Squealing Mavic Rear Wheel

Question: I have a Mavic Aksium road bike rear wheel that is about three years old that makes a sporadic loud screeching noise when freewheeling. I think it may be the bushings. Any thoughts on how to proceed? From: Dave

Answer: Sounds like your freehub body is worn out. The bushing on Mavic freehubs tend to go out fairly regularly, and when they do, you get that sound. You can try re-lubing the bushing and see of that helps before replacing the freehub. I know it sounds weird, but Mavic’s internal tech guy told me years ago to use Shimano hydraulic brake mineral oil to lube the freehub. In all my years following his advice I’ve had nothing but good results using it.

Here’s how you do it: remove the non-drive side cap on the rear axle and insert an 8mm Allen wrench to hold the axle. Now use a 5mm Allen wrench on the drive side of the axle to back off the drive side axle cap. With the axle cap removed, you can pull the freehub off of the hub shell. Do this slowly and carefully to avoid loosing the pawls. I like to put my fingers around the space between the freehub body and the hub shell to catch the parts if anything goes flying.

With the freehub body removed, wipe down the bushing and inspect it for wear. If the bushing doesn’t look too thrashed, use a quick drying degreaser to remove any gunk that may have accumulated on the ratchet teeth.

Carefully remove the pawls and springs from the hub shell and get these clean too. Reassemble the pawls on the freehub and use your Shimano mineral oil to lube the pawls and freehub bushing. Make sure that the freehub seal is clean and lubed too. A little bit of oil goes a long ways; so don’t go crazy with the stuff. Hold the pawls down while you slide the freehub body back onto the hub shell and then check that it is ratcheting correctly before reassembling the axle.

If this doesn’t cure the noise you are experiencing, install a new freehub body and lube it using the same Shimano brake mineral oil.

Welcome to our Ask a Mechanic column where our expert mechanics Daniel Slusser and Greg O’Keeffe answer your bike maintenance questions. If you have a question for us, please post it on the Art’s Cyclery Facebook Wall or e-mail Daniel directly at daniel.slusser@artscyclery.com. To see more great how to videos click on the highlighted link to subscribe to our YouTube channel and stay up to date on each episode of the Art’s Cyclery/VeloNews Ask a Mechanic Series.

2015-12-16T16:50:25-08:00