| Change plugs (or clean up, saves dosh), cos the rear one is now fouled & is shorting.
This does sometimes happen when starting.
If still doing it, check compression, cos if low will foul plugs.
I have fitted/sold some of the guys in the monster club some iriduim plugs, as these seemed to help with the older bikes.
Run ours on these too as starts better.
M600 plug: DPR9EIX-9 - stock number is 5545 for NGK
Alan | 
AK
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