corrado33

I was working on a friend's bike the other day. She had been complaining of a grinding sound coming from the cassette. So I planned on regreasing the bearings in the freehub. Unfortunately, this freehub didn't have the traditional 10mm allen inside to take it off. Looking inside, I could see flats, but it had many more sides than the allen. I'm thinking it maybe had 12 sides? Either way the 10mm allen was too small to catch it.

The hub itself is unbranded (on a cheaper newer fuji road bike), so I couldn't even look it up.

Is there a tool for this? Am I missing something? Sorry, it was impossible to take a picture.

cny-bikeman

That is a freewheel, not a cassette, and it is not recommended to disassemble either. It requires a specific tool to remove it from the wheel (comes off in one piece) probably is a Shimano freewheel. Here's a link to info about freewheels and cassette differences that also has on the page links to more detailed info on each: Freewheel or Cassette?

Also, some more diagnosis needs to be done (noise during pedaling/coasting, on specific rear cogs, did it start after specific incident or maintenance, etc.) before you dive in. The most common reason for a grinding sound from the rear is chain/cog wear or dirt/sand in the chain, not the bearings.

corrado33

No, it's a cassette. I took the cassette off of the cassette body by removing the cassette lockring. I'm looking to remove the cassette body/freehub so I can regrease the bearings.

I'm not talking about the things that catch the pawls of a freewheel.

Crankycrank

I'm guessing it still takes an Allen wrench, just larger than 10mm. Pics would help but with 12 splines it's probably designed for a 6 sided Allen.

techsensei

Some other branded and unbranded cassette hubs require either an 11 or 12mm hex key to remove the body.

corrado33

This is what I found as well. Unfortunately I doubt we have an 11 or 12mm... What a weird size.

cny-bikeman

OK, but my comment about better diagnosis still applies. You have stated nothing that indicates you have isolated the problem to the cassette, and cassettes are generally flushed out, not disassembled.

corrado33

The "grinding" sound only happens when the wheel is spinning but the cassette is not. The freehub grinds when you take the wheel off of the bike and spin it by hand. The wheel bearings have just been regreased (when I took it apart to try to take the freehub off.) It's literally the only thing that it could be.

So yes, we sprayed some lube in there and it's... a tiny bit better. It needs serviced or replaced though.

davidad

If it's a Formula hub then an 11mm allen wrench is needed. A Joytec hub can use a 12 or a combination of a 12 and a 7/16 wrench.

fietsbob

whole new machine built wheels are pretty cheap . at Retail . get one with some shimano style Freehub next time.