What’s a Freewheel vs Freehub

Bikelife Basics: Freewheel versus Freehub! What’s the difference?
These are different designs that perform the same function … locking up to provide forward movement, but disengaging when you’re coasting (not pedaling) or pedaling in reverse!
A Freewheel is a separate assembly filled with machined engagement points (and pawls and springs and fiddle little parts) that determine how quickly it will lock up and allow you to apply power. The number of engagement points usually contributes to that beautiful “buzz” that we all enjoy hearing. When I was a little kid, I used to think that buzz was the sound of quality.
Freewheels are made by many manufacturers, allowing you to easily change gear ratios, engagement speed, or sound. All you have to do is make sure your chain is long enough if you’re going bigger. Freewheels thread onto the rear hub and there are 2 general sizes of thread pitch in bmx hubs, with the smaller threads taking freewheels from 8T to 15T, and the larger thread pitch taking 16T+. If you don’t know what you have, check the web or take your rear wheel off and count the number of teeth on your freewheel, and that will tell you which size thread your hub is.
Freehubs perform the same function, but engagement teeth are machined into the hub itself, so you can’t change the number of engagement points by swapping out parts of the hub…you have to swap out the ENTIRE wheelhub. Freehub parts can be removed, rebuilt, or replaced, but ultimately you’re still limited by the engagement points machined into the wheel hub, so swapping the removable part of a Freehub doesn’t do much. This means the average home mechanic isn’t going to be changing their own Freehub anytime soon, because you have to buy a different wheelhub, and then lace it up with spokes to your existing rim, or a new rim. Depending on the hub flange height, you may need different length spokes! All this effort and cost to change the sound and engagement of your Freehub … but to me it’s worth it.
CONFUSED YET?!? Watch the 2.5 minute video and see if your questions are answered, and if not, drop me a comment and I’ll try to answer below. Thanks!
Most @sebikes come with Freewheels, allowing the rider to easily and cheaply replace or upgrade these pieces. However, there are many SE’s that have Freehubs, like the DJ Rippers, Fat Quad/Fat PK’s, 27.5” Maniacc/PO/Beastmode, and 29” #FastRipper, #MonsterRipper, #MonsterQuad. It’s like all 2021 and older SE’s with disc brakes were equipped with Freehubs, but I believe @toddlyons shifted the new 2022 Disc Brake Flyers and Big Ripper to disc with Freewheel (yay!), based on the Prototype that @rlmattrickard Rickard has been riding through NorCal.
Note: the SE Freehubs are different widths, also! 142mm for the Beastmodes/PK’s/Monsters, and 135mm (std mtb) for the Fast Ripper.
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