Ok, fairly new at this. I have a 2001 WR426 with a big gun full system, power now, and boyeson quick shot. My bike has been running pretty rich and I've changed the jetting to lean out the mix and it's almost there. A friend recommended that I go 1 or 2 steps leaner than stock on the needle. Either stock or aftermarket. I figured I'd pay 13 bucks for a stock needle from yamaha rather than try a JD kit. First of all, I ride at altitudes mostly around 8,000 to 10,000 feet locally and I'm wondering if the JD jet kit is worth it to someone that rides at high altitudes or should I stick with the stock type needle. If I put the leaner needle in will I have to rejet drastically or just minor changes. Thanks for any help.