I've got an 07 C50. I put 2" Cobra slash cut pipes on last year. It gets anywhere from 43-46 MPG. The pipes are the kind you can take the baffles completely out ( even though I probably won't) It does smell like it runs a liitle rich. A fellow rider told me he put the Cobra fuel commader on his 07 Kawasaki VN900 and it helped a lot. I have read on here mixed reviews. Any thoughts or comments would be greatly appreciated!!