Had my 660r for 5 weeks now I experianced the surging from day 1 but used the co mod and it improved drastically although not gone completely. I have put some free flow pipes on and removed the snorkle. Now this bike likes its rev limmiter even though its still so new it revs out much easier. Fuel wise i think its slightly better as well. This bike is just so easy to ride. Any ideas what to do with my standard pipes? NKUNZI