2015 300 Xc tuning tips

im currently working on setting up my 15 300 xc. great do it all bikes but jetting cannot be do it all. what I have found after owning 3 of these bikes, is this: stock jetting is ridable but can be much better if jetted for what you will be riding. more wide open/ mx riding, need to richen the circuits. tight woods/ single track can go leaner on the circuits. I"m somewhere in between riding on a rough whooped out gncc type sand track. I have played with richer/ leaner main jets, stock 172 seems best so far, leaned needle position, felt flat, went back to stock clip position. I have a Suz necj needle on order to try next, alot of guys here like the Suz needle. I also will be trying a richer pilot. trial & error, luckily the carb is ez to get to, so adjusting needle clip position & jets is done quickly. I also run just a splash of race gas in my premix, 25%. I add 1 tooth to rear sprocket, enables me to use 3rd & 4th as main gears... again all depends on what type of riding, terrain ect.

Suzuki needle is a must have IMO. 172 main for mild temps and a 42 pilot.

As far as the powervalve, I'd stay with the yellow spring or use the green (soft) spring. You can fine tune the power more with the square head bolt on the powervalve adjuster. I like mine flush of just a little further past it.