Hi,
I have just bought a gsxr 400 with slip on K&N filters and a stubby micron oval end can. Due to the noise I've changed back to a standard end can which has made the mid-range rich. Top end is ok once it has cleared but the can is blackened with the over rich fumes. Anyone have any ideas. I've thought about lowering the needles to lean out the mixture and wondered if this will do the trick?
Thanks
Deacfo

That may well do the job. It's quite possible that when the bike was setup to run with the K&Ns and slipon the needles were raised.

Thanks for that. It seemed the easiest thing to try first before mucking around with the jets and mixture settings

:D