Hi all. Does anyone have any experience with Yamaha's 2 wheel drive WR450 2 Trac? Mine is the 2005 model (last of the steel frames), with the full Ohlins set up including steering damper and 2wd system. I'm looking at removing the standard exhaust and replacing it with DEP's System 7, as well as the air filter with a K&N , so any ideas as to what jetting would suit said alterations? The bike is completely standard, and has only just been run in and serviced accordingly. Has anyone altered the gearing with the 2 Trac system without changing the pump ratio? I'm going to be running the bike on the road as well as off, so will want a bit of speed to avoid being overtaken by busses!