My 900ie-engined MH900e has been exhibiting signs of drama recently, spitting and stalling through the New Years Day parade. It only has 5,200 miles on it. Engine modifications include EVR1 ECU, low restriction air filter, Staintune exhaust.
Last weekend it would only light one cylinder; checked the plugs and both had spark. Odd. They looked dirty - probably the effect of the last spitting outing. Cleaned them both up with brass brushes, fine paper, carb cleaner and re-gapped to 60mm. Then the bike wouldn’t start at all. 
I’d heard that no amount of cleaning will bring back some plugs so binned them.
Replaced the stock Champion RA6HC with equivalents NGK DCPR8E (which take a larger 12mm socket, darn it). Vroom! All cured. In fact, smoother than ever - leaving me surprised at the difference plugs can make on a modern-ish twin. I thought spark plug voodoo was the domain of bevels!
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