Hi new to the forum. I have an issue with a 250sx. I am trying to sell for a family friend who has passed away. It runs good up to about 1/2-3/4 throttle but when you go to full throttle the revs go up amd down? Any ideas what I can check to correct this. Any ideas are appreciated... Also any idea of what a 1985 250sx in great shape should be sold for? Thanks

 

hey i own one myself sounds like it could be the carb adjustment at the bottom of the carb it is a very little flat head screw it could be running to rich or to lean usually turning the screw in is rich and turning the screw out is lean the best way to adjust is to do it while its runnning and at full throttle this way you can hear whats happening as you adjust the only thing is its gonna be a little warm under there so be careful also i bought mine for a grand thats usually bout the price i see them for

 

probaably a problem with the carb

 

I don't think I would make any carb. adjustments or anything for that matter while it was running at full throttle. That's just me though.