Welcome to our Ask a Mechanic column where our expert mechanic Daniel Slusser answers your bike maintenance questions. If you have a question for Daniel, please post it on our Facebook Wall or e-mail Daniel directly at firstname.lastname@example.org.
Thanks for your blog post on how to adjust loose ball bearing cup and cone hubs. I have a follow-up question. How do I remove the part of the hub that the cassette sits on (it is called a freehub body, right)? Mine won’t engage anymore and it needs to be replaced. From: Skyler
Skyler, you have your terminology right. My advice is to free your mind, and your body will follow. That is, learn the correct mechanical technique and your freehub body will more fully resemble its namesake once it is separated from its hub bound perch.
Freehubs attach in many different ways depending on the manufacturer and the specific model. In order to remove the freehub on the Shimano M525 hub that was discussed in the last post, start by removing the axle and bearings as described using the appropriate tools. Then, use a 10mm allen wrench inserted into the drive side of the hub to remove the freehub fixing bolt. This is best accomplished by clamping the allen wrench into a bench mounted vice and use the wheel itself as the removal lever by twisting the wheel counter clockwise with the drive side facing down and engaged with the allen wrench. That is all there is to it. Just reverse the process to reinstall the freehub body.
Note: Some non-Shimano cup and cone hubs use a similar attachment scheme but the fixing bolt is accessed from the non-drive side. A few of these hubs require either a 12mm, 14mm or 15mm allen wrench rather than the more common Shimano 10mm.
Daniel Slusser is a professional bicycle mechanic with over ten years of experience. He holds a bachelor’s degree in business administration from HSU and a master’s degree in history from Cal Poly University. When he is not riding, wrenching, or writing he enjoys spending time with his wife and two children.