dont do big bore reliability goes down hill i feel like keep her strong running 450! i was gonna get that same exhaust but came up with money for the FMF 4.1, where are you located there is a place in in near west springfield MA called BCS powersports they did Hetricks engines few years ago when he was sponsored, great ppl, i had my YFZx done there runs like a bat outta hell for mild mods!
I'm in NJ.
I read more bad then good for the FMF on the R.
Yoshi has been proven to be the best and quietest exhaust for these bike. But if you know something I don't let me know.
I'll look into them. Just checking options now.
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