Dyno Hub Rotating In Forks

[sean_iow]

I thought someone else had the same issue before but I did a search and couldn't find anything. Apologies if this is covering old ground.

After my ride at the weekend when I was cleaning the bike I noticed the hub had rotated in the forks - the centre section before anyone replies and says that's how the wheel goes round What's weird is that it appears to have rotated backward, i.e. not in the direction the wheel rotates



One of the wires was just still on the connector so I don't think it rotated all the way round to that position. The axle was tight in the forks, QR15. I did wonder if a stick or something might have come up and pushed it round but seems unlikely to have just done this and not damaged a wire? The hubs been on for a week so far with no issues on any other rides.

Has anyone else had a similar issue? And if so how did you stop it happening again. I find getting the connectors on a bit of a fiddle, much harder than it was with the SP/Shimano style connector. I'd struggle to do it with cold hands so I'd prefer if they didn't come off mid ride.

[lune ranger]

Had that problem with a Love Mud Juice. It wrecked 2 sets of cables/connectors.
In the end I got a refund from Alpkit because I couldn't stop it happening.
Is that a SON?
I've had one SON for 10years (100mm QR) and it's never happened. I have another SON now and that appears fine thus far.
Good luck with solving the problem?
The connectors on the SON loosen up with s bit of use so getting them on and off gets easier after a while.

[sean_iow]

It is a SON, I have a recollection of the same thing happening occasionally with my SP which I had before in the same forks but I'm not sure or if I read about someone else having this issue

It's the fact it seems to have rotated backward which has me baffled. I'll clean up the drop-outs in the fork and see if that helps. Hopefully it's a one-off.

[lune ranger]

I think mine went both ways ( )
No amount of cranking the QR down hard etc helped. I just had to keep an eye on it when riding.
I guess it's possible that all hubs may shift around a bit but you only notice it with dyno's

[Trail-rat]

What hub is it . I had this issue with a 15mm sp hub.

Scotroutes also had it iirc.

The fix was to file down the qr adaptor so that the fork legs clamped the hub body rather than onto the adaptor.

[sean_iow]

Mine's a SON 28 15, so a 15mm axle, in a 100x15 fork so there is no adaptor used. The only thing I can think of is that if the fork flexes and one leg flexes more than the other that it might move it round a bit each time. I'll make sure the interface is clean and grease free.

[ScotRoutes]

Precession will cause it to rotate "backwards".
It sounds like the part with the dynamo connector isn't being clamped firmly enough but without seeing it in close-up it's hard to diagnose.

Is it by any chance fitted to a set of Rockshox forks - the type that can take Torque Caps?

[sean_iow]

The forks are Travers Prongs. They were on my previous bike without any issues and made it round the HT550 with a dyno hub in and it didn't rotate.

I was ok on my ride out to my bivi spot at the weekend as the light was working when I stopped. I didn't plug the light back in when morning came so it must of happened on the 16 miles back to my house... either that or the rabbits moved it whist I was asleep

[rufus748]

I've got a son on Travers prongs. It happens occasionally, usually if I haven't tightened the axle enough, i.e more than I think it needs.

[Retiredtester]

I had a similar thing with an SP dynohab. I thought about filing the axle down, but didn't fancy it, so ended up laying a thin 25mm long fillet of sugro so that it covered the junction between the bit that rotates and the fixed section next to it. The adhesion was just enough to stop the rotation and it's been fine ever since.