I just put on a new FMF Gnarly pipe and Turbine Core silencer..and am running rich with the stock jetting...since then after about 100 miles of riding I started to get a strange noise which was described by many as piston slapping. Opened it up and there was some side to side movement on the piston in the cyclinder. So i got new wiseco piston and rings (standard size)..no gouges or scuffs on the cylinder wall or piston. there was a lot of moist carbon buildup on the piston and plug. Will also be adding boyesen reeds..non carbon ones...Should I be Jetting the carb too or should I see how it feels first ?:think
Go to the JustKdx website and follow the jetting WOT instructions to get the correct jetting for your bike. I have the 99 KDX 200 with FMF K-35, no airbox lid, FMF Core II, run 32:1 and moved to a 45 pilot and 155 main. The 152 main worked when I did WOT testing but it was 95 degrees out so I play it safe with the 155, stock needle, 3rd clip air screw 1 out. The bike rips.