Starter's falling to pieces

I was out this weekend with my friend on her new to her M800ie and on the last leg the bike refused to start.

After much cursing and investigating it was concluded the starter was stuffed and the bike was recovered back to her house.

Upon inspection the magnets around the starter were broken and pieces had jammed it stopping it turning.

Exactly the same thing happened to my old M600.

is this a common thing? Any idea why it happens?

I had the same thing on a low mileage 600 so it is probably quite a common fault. " Why does it happen"
it,s almost certain to be the quality of the components

[Mossleymonster]

Mines an 09 1100 and the starter is as rotten as a pear to look at. This winter will see it dealt with.