Alton rotor failures

A friends Alton rotor came apart and I have one that was doing the same, has anyone experienced this? Just more reason
This is mine.

this is my friends

Mine didn't fall apart but it did have some odd marks on the outside and lost magnetism. Alton suggested it must have touched the stator. If it's out of warranty you can buy the magnet ring separately from Alton themselves. RGM do stock some Alton spares but only the sprag assembly complete.

I have had my Alton for 1 1/2 years and the rotor looks fine.
Your picture with #3 marked on it shows heavy scoring so my guess is that either clearance wasn't correct or there were some sorts of particles floating around?
But what really perplexes me is that the second number 4 marked photo shows in upper left that the metal skin surrounding each of the magnets has been pressed down around the magnets so you can see each magnet profile. Its almost like that the chaincase oil was so thick that
it hydraulically pressured the metal skin in.
Anyone have any ideas?
Dennis

Yes I had one that came apart , mine is belt drive so runs dry , never worked out why , took the stator out at the same time had plenty of clearance , about 3 or 4 years ago . mine is now 11 years old , had to have the motor rewound couple of years ago spins the engine better then ever now

Looks like insufficient clearance and/or an alignment issue. My Alton has been on the bike since early 2013 and has been a total non issue as far as any sort of maintenance/adjustment/problem. IOW, I have never noticed it's there other than to start the bike.