As asjdsm has explained it very correct, but I did replaced it on first roll because mine was not even LG it was LTC or some thing I dont remeber...
So I put in NGK , now the funny part which I am going to tell you please dont laugh :D:D:D after that I never replaced it again still the same I get it clean after two three months I dont get my bike tuned only oil change and filter cleaning and after 2/3 months I only get the tappet adjusted and plug cleaned thats it... (feeling like a Kanjoos guy now :$
heh eh ehhe)