Hi,I've posted a while back on this issue which is pretty crazy.I have a 98 sp500 I bought originally for parts that needed a cam, the previous owner said he also had carb issues prior to the wiped out cam.I replaced the cam with a Scrambler 500 cam, cleaned the carb and it run. With the air box connected it will run 47mph wide open, with the filter completly removed "just the tube to air box 47mph", if I disconnect the tube from the carb it will run 63mph according to my gps and my buddys Can am. Am I missing something, how can it run 63mph with nothing hooked to the carb and how can just the tube connected to the airbox with no filter or lid on the box make such a difference in top end speed "it's just a hollow tube"??

 

[img]i/expressions/face-icon-small-happy.gif[/img] check jetting and also look for worn needle and seat.With no filter air increases allowing to run leaner. Test run,kill ignition,check plug color to see if too lean also.