Running a hotter plug than usual?

So I've become the owner of a new to me 2001 XR650R Supermoto. The bike has been uncorked, and is apparently setup with the stock carb, FMF 4 Powercore Header / muffler, after market filter. Since the bike has been hard to start, I looked into changing the spark plug. After getting to the plug I surprised to find it was a NGK BKR6E instead of the stock BKR7E the manual recommends. Is running a hotter plug bad for the engine? Or is it hiding some other condition with the bike I should be aware of?

The plug can be bad for the engine. The PO might have been given the wrong plug by the pot smoking kid behind the counter and the local shop just installed it. It's as likely to be an accident as anything else. Plug science gets pretty complicated and I don't understand it all by a long shot. But I don't think there's anything here to suggest a different plug is needed.

T-4 pipe is generally the best pipe for you r bike. But FMF is fine.

If the scoot has grown up on aftermarket air filters you might check the intake calves for chips unless it's been a 'tard bike.

Hard to start is usually the same jetting problems 90% of the bikes have. Get the carb sorted out by a pro if you aren't comfortable doing it yourself. I have the stock carb and it starts as easy as an Edelbrock I think. Team Honda never ahd any problems with starting it...

Congratulations!

pedal pusher wrote:So I've become the owner of a new to me 2001 XR650R Supermoto. The bike has been uncorked, and is apparently setup with the stock carb, FMF 4 Powercore Header / Muffler, after market filter. Since the bike has been hard to start, I looked into changing the spark plug. After getting to the plug I surprised to find it was a NGK BKR6E instead of the stock BKR7E the manual recommends. Is running a hotter plug bad for the engine? Or is it hiding some other condition with the bike I should be aware of?