Mavic Aksium freehub change problem

[hoogerbooger]

The old freehub had play on the cassette. So I changed the bearing on the freehub. When I put it back on the cassette wiggles laterally if I turn the axle.

I took the freehub off and put a brand new freehub/bearing on. It did the same. turn the axle and the cassette wobbles laterally. the axle however looks straight when it turns, just the cassette having a lateral jiggle.

If I rotate the cassette forward, it stays in a straight line with no wiggling

My head hurts, I can't work out whats wrong....

anyone's brain working better than mine....and can advise ?

[rjb]

Play in the freehub is most likely due to wear on the nylon bush. Replacement bushes should be available.

I see you've been tinkering with this for a while. It's worth reading the thread and the various links it refers too.
viewtopic.php?t=155146

BTW as you rotate the cassette forward it moves with the bush IE no movement between bush and cassette. The bush only rotates with respect to the cassette when freewheeling. This could explain your issue.

Here's another interesting article. "How does a Mavic Freehub Body wear out? - RogueMechanic" https://roguemechanic.typepad.com/rogue ... _mavi.html.
There's a link in there to replacing the nylon bush with a ceramic bearing at some cost.

[hoogerbooger]

Cheers rjb. It wouldn't appear to be the nylon bush as it does the same with a brand new freehub (with new bush).

( The previous play may well have been partly the bush. Even with a new bearing in there was still a bit of lateral play....but a lot less)

Wheel is in the bike now ( with the new freehub) and everything runs straight ( wheel rim; freehub/cassette). virtually no lateral side play at the cassette when you grab the big sprockets and try to lever.

However take the wheel out and turn the axle and the cassette does a lateral wiggle !????**@.

My confused head thinks:
- when you turn the axle (LH end) the only part that physically touches the freehub body is the freehub bearing centre and locknut on the RH end.
-It's a 9mm ID bearing on a 9mm axle ....which fit on easily...... so a tiny bit of play because of this and because even a new nylon bush is not as good as a bearing.
- As virtually no lateral play at the cassette, I initially thought the axle must be bent at the RH end.......but staring at the right hand axle end when I manually turn the axle from the LH side ... the RH end stays straight while the freehub wobbles laterally.
- I'm left thinking the freehub bearing is not in straight and the bearing twisted between the inner and outer shell. But can't see how that would be the case unless the seat was machined badly.......and it would have to be on both the new and old freehub.
- If that were the case..... when the quick release is on the axle is clamped in place and the the alignment between the cassette and the front chainrings will vary a little each time I take out and return the back wheel. but gears all work so not enough to be a problem there.
- However if the bearing is a tad out of line with the axle.... the twist between the inside and outer shell will presumably cause quicker wear.
- ??????

I'm be most interest if others have noticed similar issue .... (or am I just going mad)


( oh yes...Re previous post, having got the parts, I decided to let the bike run with the lateral cassette play until the Missus had done Ride London. Glad I did, as I would have completely stressed her out with this !!)

[rjb]

What are the hub bearings like? Any play in them? Any signs of wear on the hub body where the bush rubs.?

[Valbrona]

I have a feeling you are using a newer style freehub body where an older style one used to be. I recollect that there are two types, the newer one requiring the use of some kkind of thinn washer in the arrangement. At least I think so.

NNew freehub body 30871101 fits many Mavic road wheels. This freehub body supercedes the M40592 freehub body. The kit consists of the freewheel body, internal washer and bushing to facilitate both 8 and 9 mm diameter axles. When installing the new freewheel body to older wheelsets (pre-2013) it is necessary to use the silver bushing

[hoogerbooger]

The bushing is used on 8mm axles that were produced up to 2013. Ours is a 9 mm axle and the bearing is 9mm ID

RE hub bearings: there's no play at the wheel rim. I didn't check for play at the axle with the freehub off yesterday......but believe I did when I removed it circa 6 weeks ago...and there was no play....but will check when it comes off again....and any wear on freehub body.

However I can't see how wear at this end of the freehub would cause the symptoms....with no play at the rim......If the RH wheel bearing was worn I think I'd see the RH end of the axle moving in sync with the cassette when I turned the RH end of the axle.

[hoogerbooger]

Should anyone be interested, here are the answers to the questions I asked:

1) Yes I am an idiot ( for those who didn't already suspect)

2) Valbrona nailed it ( and rjb links). Whilst being Adam Ant that I had a 9mm axle, the vernier gauge has politely disagreed with me. Perhaps it is better to make fact based decisions, than rely on ingrained untruths ? I could be convinced....

3) Previous freehub bearing was 8mm ID. New Freehub bearing 9mm ID. Once I had swapped out the plain washer for the top hat version for 8mm axles.......the freehub/casette is not dancing anymore. Interestingly the wheelset is the Aksium One Disc, bought in 2015. The PDF on the Mavic technical site is also dated 2015 and I had presumed it wasn't made before 2015........sounds like it was though.

I anticipate an increasing number of senior moments now that I'm a dodderer.....but am happy with this confession of stupidity as it has lead to no new cost.

Thanks for your comments...you helped me work it through.

[rjb]

Some of the Mavic documentation leaves a lot to be desired. My Cosmos wheels bore no resemblance to the official service documentation. The design had changed without the documents being updated.