Rear hub disc mount a bit wobbly

[bazzapage]

The problem with the rear disc mounts on the legacy Turbo's is that the screws are a bit short, and can get wiggly over time ultimately stripping the threads. You can feel this as play in the system if you grip the rear brakes and rock the bike backwards and forwards.

Q: Has anyone found a permanent engineering solution to this?

[I have used a thread repair epoxy which doesn't seem to last either, and now have tried glueing the disk to the hub in addition to take out some of the shear forces. Is holding after two rides. But obviously I'd prefer something a bit more robust.]

 

[Tonqin]

Is this where the rotor bolts onto the hub? That's a worry.
You can get thread repair kits but you'd have to see if the rotor bolt holes allow a bigger bolt to make it work.

 

[bazzapage]

Yes it is. It's hard to tap with regular taps because it's a blind hole.

 

[bazzapage]

For the record, I took this to a 'cycle engineering' shop and they did the following, which I hope is a permanent solution:

• unlaced wheel, removed motor cover/flange
• drilled in stainless steel inserts as deep as they could go without impacting the wheel bearing which sits behind the screw holes/flange. He reckoned the original casing material was too thin and too soft for its purpose as flange for the brake rotor.
• replaced screws with longer screws with a washer & spring washer, secured with blue loctite (see picture - there is enough clearance). The idea of the spring washer is to maintain proper tension.
• replaced cover, re-laced wheel.

Didn't cost much, $150.

[Also for the record, the 'epoxy glue' solution I tried previously worked for a few days but actually held it all together for a few months. Mechanic cursed me, said it made his job harder and broke a tool (which he charged me for of course).]

 

[Tonqin]

Nice work, did you relace to original rims again?
Your cycle engineer isn’t Bruno is it?

 

[bazzapage]

Nice work, did you relace to original rims again?
Your cycle engineer isn’t Bruno is it?

Yes, Bruno. He is one-of-a-kind. He was horrified by the engineering in a Swiss-made product!

Original rims yes, it is a Turbo S wheel so a nice rim. Front wheel is an original base-model Turbo wheel.

Both wheels now tubeless which is very nice