ManI've seen big bore bikes with only 6 over swing arms, if you can control the clutch on a launch this is all you will ever need unless you turbo it then a little more may be necessary (Romes Bike). But I agree with evryone else on the shock thing, just did a 100 Gixxer for a friendof mine (260) and I had to turn his shock settings all the way up may as well had been a strut, lol, but his swingare extensions are holding VERY well.