I own a 2012 DRZ that I picked up last year new and I now have approximately 1,500 miles on it. For mods, it has an HT skid plate, Clarke tank, TT case guards, stock handguards, Pirelli Scorpion XCMH tires, 14/47 gearing, JD jet kit, Uni-filter, and the 3x3 is done. My current jetting setup is per the JD recommended settings for high altitude (4000 to 8000 feet): #25 pilot jet, #150 main jet, RED needle in the #3 clip position, and fuel screw 2 ½ turns out. The setting has worked well for me and the bike runs great, although possibly a little bit rich as it doesn’t start quite as well as it did with the stock jetting. So my question is this. I got a great deal on a Leo Vince full exhaust system through their website ($274.00 shipped for the full exhaust) and plan to install it this weekend. I’m thinking that since it is a bit more open than stock, I’ll need to bump the main jet up to #155 and leave the rest of the settings alone…thoughts?