Hall Sensors?

["abbot@xxxxxxxxxxxx" <abbot@xxxxxxxxxxxx>]

I had a wonderful two weeks riding in the White and Green mountains  
the first 3 weeks of October. The day that I started back to Toronto  
the bike started easily and as I was turning around it stalled, as it  
often does when cold but absolutely would not restart. It cranked and  
cranked and I could hear the fuel pump pumping but nothing, nothing  
fired. Finally I had to leave the bike with a neighbour (who is an  
Anonymous member) and return to Toronto via cage. (My wife and puppy  
take turns driving the car while I ride). I was able to arrange with  
Max BMW of Portsmouth to pick up the bike this week and take it in  
for repair. (A great service by the way, they are at least two hours  
away from where the bike was left.)

On Saturday I got the verdict, the Hall sensors had shattered. It  
apparently took a long time to diagnose, as none of the usual  
diagnostic paradigms worked and they finally disassembled the  
charging system where they found the damage. (The upside is that I  
get to do a late season ride back to Toronto)

My question what's a Hall Sensor and more importantly, what could  
cause it  (them) to break/shatter. Is there anything i can do to  
prevent this from happening again?

Thank you for any insights.

Nahum Sloan, Toronto
1999 R1100R

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