My 1991 xj900 has had spitfire plugs fitted but a guy said they may burn to hot for my engine. Is this the case? and what is the best spark pluge to fit this bike any way. Thanks in advance for any help given.
P.S. my mate cleaned my bike for me then went to a local bike show at Luton and one first prize for the cleanest Jap bike so I geuss he must have done a decent job then!

Know this is late but NGK BP7ES Is best for this bike in my opionion.

Thanks for the reply. I ended up fitting a set of nkg`s just to be safe as homer racing used to races on them and quit the sponcership because they kept letting him down in races.