Other hallfs back wheel is slipping, i have a chain checker, so can probably eliminate that cause and logic suggests it is the freehub.

I have a shedful of spare wheels but all have something wrong. I foolishly didn’t label them. So some have spokes fixed but are inherently weak, some have dodgy freehubs.

Is there a way of knowing whether a freehub is kaput without putting it on a bike and pedalling?

take it off the hub & take a look – might be easier to ride it though, if you will be able to tell by doing so

Riding would be the test, but can’t be bothered with fixing tyres, cogs. How can you tell by removing and looking?

look at the pawls (assuming that’s what it uses) and check far damage (if nothing obvious, compare to photo of the same model ?)

you might even find that taking it apart & cleaning it could fix it

Many free hubs can’t be inspected. Eg shimano. Flush it out with petrol and then fill with something like chain lube

Shimano sadly. Sheldon refers to a legendary freehub oiling tool that screws in and keeps things contained, but I think they’re now rare, along with the much fabled hypercracker.

TBH a ride test should establish it, chain and freehub slips feel very different. (not messing about with other wheels, just riding it exactly as it is)

Sorry, should have been clearer. I know the one on there is goosed. it’s the 5 spare wheels in the shed, one of which has a good freehub, which I want to test, preferably without fitting tyres and cogs to each…

and does anyone know if freehubs really aren’t as interchangeable as shimano want you to think?

Stick a chain whip on it and give it a load of welly. If you slam your elbow into your ribs or punch something, the freehub is knackered.

That’s it GS, great thinking!

The sound is a good guide…

Mine, not shimano but sunringle has just done the same thing and a quick 30mins strip down uncovered how much dirt had ingressed into the feehub. I cleaned it up and now it is back to normal. Hopefully this gives you some hope as to it being a relatively easy fix.

The symptoms I felt/heard were:

– Not as loud as it used to be ( although this can be hard to notice as it is a gradual process and weather e.g. wind can make you think it is still as loud just the wind is noisier.

– Pick up wasn’t as fast as it once was.

– A slightly hollow sound coming from the rear end when climbing on lovely flat paths. It sounded like a hollow shell which had a bit of play in it. I thought this was a tyre but I believe it was actually something to do with the free hub as my wheel bearings are OK.

Park Tools provide a very comprehensive guide on their website!

and does anyone know if freehubs really aren’t as interchangeable as shimano want you to think?

Quite a few are depending on which models you have, but it might be a bit involved, it’s not like whipping the FH off and replacing it on a Hope. You’re going to have to basically fully disassemble both hubs and rebuild one from scratch, including loose bearings and setting cones… Not everyone is up for that.

So what hub do you have to fix (model no?) and what potential “donors” do you have?

Also I find it can take the power of greyskull to remove some shimano freehubs (and a 12mm allen key).

TBH i’d just replace it with a new one. If the OH rides the “repaired” bike and it’s slightly goosed it’s probably not worth the grief?