My brother just bought a 2001 Xr250r that has an aftermarket exhaust on it. He also got the original. I have a 92 L which has the restrictive muff on it. Will the 01 fit onto my bike, or would I need R headers? Bolt patterns be in the same locations? I haven't had a chance to look at the 01 muffler and probably won't for a few days. Also, just ordered a 12/45 sprocket set and chain. The L sucks on the tight trails and has no balls when it comes to loopy hill climbs.