I've been running FMF Gnarlys for a couple of years on my 2. Like GlennP said, jetting is important but also the intake. Check out a V-force reed cage. As far as durability, I've tweaked the gnarly just as easily as any other pipe, even flattened one beyond pancake. BTW, the 200 powerband is somewhat centered on the mid. I don't really think that over-rev would give much more power anyway. That's my two cents. Cheers
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President,ETRA.
'01 KTM520E,
'99 KTM200E,
'93 CR500R
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