Check out this link and read the archives.. http://groups.yahoo.com/group/xrlug
Do you know if the cv carb slide has been modified? Baja designs and i think Dynojet have a kit to do that, about $20. These bikes are pathetically lean stock for emissions reasons being a factory dual sport.
I canned the cv carb for a 41mm mikuni flatslide, k&n filter, 102.4mm 10.25 to 1 comp piston for 675cc's, megacycle cam and big gun exhaust. If you want to raise the compression you pretty much have to do a cam if you want to use pump gas.
I couldn't get the link to work but if you go back to about page 4 and read the thread on the xr440 kit there is a ton of good info, best of luck!
thanks for the tip- lots of good info, will try a few things to see how it works- I love the bike, corbin seat, desert tank- great for comfort on long rides- hope this will help with the power