I gave my rear pro 2 hub a full service tonight – new bearings all round – but neglected to put the spacer back in the freehub. It sits between the three bearings and sort of ‘floats.’ Is it crucial that it goes back in – the hub seems to be working ok without it? By the time I realised I had finished the job.

You’ll have to put it back in, it stops the bearings mating & having babies.

Lol! What’s it purpose? Seems to have a similar function to that of the sleeve in hollowtech 2 bottom bracket bearings.

It needs to be fitted. Without it, when you put the wheel back in the frame and tighten the quick release, your freewheel won’t freewheel.

I think it’s just there to stop the potential of the bearings moving inwards, which is hardly likely IMO.

Only kidding again. It has to be there otherwise when you tighten the skew…….

Damn, beaten to it! 😉

Bugger.

BTW I know this from experience. 😳

Edit
It shouldn’t be too big a job. Take the cassette off, pull out the drive side qr spacer, pull and twist the freehub off, drop the spacer over the spindle and rebuild.

Look on it as practice for next time.

http://www.hopetech.com/webtop/modules/_repository/documents/PROIIREARassy.PDF

Without the spacer(9), the freehub bearing(8), fouls spindle bearing(12).

I think. Sorry.

Yeah, it shouldn’t be much hassle to do but it’s still a pain! I think I was focusing too much on ensuring I got the spacer between the freehub body and hub shell in.