Sunday, March 15, 2009

Hub how to: Freehub Replacement

So what's involved with removing / replacing the freehub? It's very, very simple. Whether you want to lube up the pawls (recommended each year - 10W30 will suffice), switch from Campy to SRAM / Shimano (or vice versa) 0r replace a worn freehub body ($40 if you need one), it shouldn't take more than a few minutes. Here's how we do it:

Remove end cap.

Place a 5mm wrench in each end cap. Try to apply leverage to drive side so that cap comes off first.

You'll notice (green arrow) that the multitool I'm using here is named "The Cooter." This is a TREK tool that was originally named after Ben Jones character on "The Dukes of Hazzard."

Mr. Jones was apparently none too pleased with this use of his fictional namesake because soon after the tool was released, a TREK rep came into the shop I was working for at the time and gave me a box full of these things because they were no longer allowed to sell them. They were immediately rebranded as the "TREK multitool." I still have a half dozen of these - they are quite handy.

Okay, so now you have the end cap removed. "But wait," you say. "I've incorectly applied too much leverage to the wrong end cap and the one I wanted to remove is still there."

No worries, just find a 10mm allen wrench and stick it into the end of that nice big 15mm alloy axle.

Another twist of "The Cooter" and you're good to go. Once the end cap is removed, just pull off the freehub. Take a look at the hub. Make sure no pawls are stranded inside (green arrow) and make sure the little silver washer (red arrow) is still there (sometimes it likes to stick to the freehub as you pull it off).

This is a good point to show that there are 34 engagement points on the hub body and 3 pawls on the freehub.

Okay, so now you've cleaned up and oiled the old freehub or have a replacement ready. Simply slide it back on and twist counter clockwise as you seat it onto the hub body. Replace the end cap and tighten with a 5mm wrench. Tighten securely but don't over-torque.

That's it! Super easy - just like I promised. Eventually, I'll show how to completely disassemble the hub and replace the bearings. It's pretty straight forward as well but for most of you without ownership of a bearing press, you'll want to take it to your LBS for this.


blove said...

Oh sh#t, my name IS Ben Jones. I never realized...

-JK said...

Ha! Sounds like someone has a new (and unfortunate) nickname.

Joffery Stark said...

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