Look at this dyno run for a 250r, they tested like 3 or 4 different pipes, and put them all on one dyno run sheets, but they were all hittin top HP at about 4K RPM'S, what is up with that?? And then they totally die to no HP at around 6K rpm's, are they just throwin in lines there to show you how much top HP they had? Cuz i know damn well they weren't hittin top HP just goin into mid range, and had no HP on top end. http://www.atvsource.com/images/arti...s_fmffatty.jpg
Idiot, it's testing out pipes for a 1986 honda 250r, a 1988 lower end with the stock 1986 crank bolted on, with a 68mm bore job. I watched a guy come in 3rd in a harescramble in the double A class on September 31st on a 1998 XR250r, pretty wimpy eh?
you ever ride a 400f or a 250f?? the 400 and 426 do put out 50 horses wich is alot, and the 350f puts out more power than you could handle, dont know the excat figures for the 250 and 426, but hers a thing to know about yamaha, there figures are usaull a little conservitive meaning they said its got a little less than what it actually has