Hi

I hope you can help explain the reason for the failure of my rear wheel hub.

I have a 1969 AT1 that I bought with 5000  miles on it 3 years ago. I have covered 6000 extra miles and today whilst checking the bike I noticed play in the rear wheel hub. To my horror it was not the bearings that had failed as I suspected but the bearing housing on the drive side had completely disintegrated - see photo. From the signs of rust it would appear it had been broken for sometime. I do not ride this bike off road and there were no signs of a problem when riding. What I would like to know if anyone can help is.

Is this a common problem?

The wheel did not have the shim shown as number 43 in the parts list drawing fitted. Could this be the reason?

The cush drive was difficult to remove. If this had fix itself tho the wheel with corrosion causing lack of movement could this have stressed the hub?

Any help would be much appreciated because I want to avoid future failures.

Regards  Jim
 

Well that's a first. Never seen that happen. Complete wheel shouldn't be hard to find. Same wheel "by memory' from AT1 to AT3 including CT 175 versions.

Looking at the corrosion there i would say that's been on its way out for a while.
Have in mind though,it's at least 48 years old and has probably seen some action in that past life.
Good shout though.
Usually it's the circlip flange that go's but i haven't seen that failure,until now either.
 

I guess the spacer was in there between the bearings?, not that it would cause that particular problem, just stuff the bearings by trying to draw them together--sort of.

Thanks for your comments. I am pleased to hear it is not a common problem just my bad luck.

All the spacers were fitted. The wheel would have been checked during the bikes annual MOT test, by a professional, at a UK government test centre in 2018 and given the OK. The rules changed in 2019 and these tests were no longer necessary for vehicles over 40 years old. So this is a lesson learned and I will now carry out regular checks on all my historic bikes.

Very few parts are available for AT1 in UK as it was not imported here and the likely freight costs for a wheel from America would be $100. The good news is I have managed find a wheel in UK at an acceptable price so problem solved. 

Thanks again for your help.