"Underseat exhaust doesnt really suit that look, but it thats the way your going to go, why wouldnt you use an arm from a bike WITH an underseat exhaust so you didnt have to run it around the outside. Put it up through the arm like most do." it is a swingarm from a bike with an under seat exhaust, its from a cbr1000r "Interesting. Funny mix of styles. GS550 engine ? Wouldnt be my choice of motor. There are a couple of featherbed Suzuki's that use the later oil cooled Bandit/GSXR engine. Alrthough you have an oilcooler its still has fin's on the motor and doesnt look all bad (and go's hell of a lot better)" its not as slow as you might think,revs easy to 11000, i managed a 62 second lap at brands hatch , now has a 672 top end and slabie 29mm flatslides though, so little extra go for now