I picked up a 2006 KLX110 for my grandson for $750 - stock. It looked pretty good with added decals. Took it out right away and ran ok, but pretty hard to restart. Seemed to restart only after sitting for a while. I took it home and cleaned the carb and air cleaner. Changed the oil and filter and installed new Champion spark plug (O'reilly's didn't have the NGK). Took it out last Saturday to Hollister Hills and still experiencing hard (almost impossible re-start). It runs very good once it starts. Tried to re-start it for another trail ride, and no start again. A younger man managed to start it after kicking the hell out of it. Later at camp, I checked the spark (visually) and I thought I saw it spark once - maybe a weak spark. I bought a new NGK plug and starter fluid, and it fired up after a few kicks, but was still hard to re-start later. One guy said I should change the carburetor. Earlier, I spoke to a guy who had experience with the KLX110. He said the carb air jet is sealed (capped off). and he fixed his by removing the cap/plug and somehow (he is a machinist) modified the jet to allow manual adjustment. Should I try to modify my carb or buy a new one? The on-line parts houses have CARBs for $95.00 for the Canadian model - the US carbs are more expensive. Would the Canadian model have the adjustable air screw? I am thinking maybe yes. Would the Canadian Carb be better than the US Carb? Or, someone on this site recommended a Mikuni VM26 Carb. Is that the way to go? But I read (I think) that the Mikuni Carb won't fit the stock air box boot - is that right? Any help from you experts would be greatly appreciated!!!