Hello All, First post here so take it easy on me. I recently bought a 1999 CR250R that had been stored...it was basically new with very very few hours on it. Last night I decided to dig into the carb to determine what it had in it for jetting, here is what I found. Main Jet 168 Slow Jet 40 Needle 2nd from top Air Screw 2 turns out Bike was always at my altitude in Central Oregon 3200' give or take. Last I rode it (Before we had 3 feet of snow) it ran awesome. Temp out were mid 50's As per the OEM Serivce Manual, for that temp and altitude, it says it should have the following; Main Jet 188 Slow Jet 42 Needle 3rd from top Air Screw 2.25 turns out Should it be this far off?? The smallest Main Jet the book listed is a 175 and a 42 Slow Jet across the board. It just seems that what is in it now is quite lean except for the Needle position, but it runs great. I am getting ready to go ride at a lower altitude (1000 to 1500 or so), Temps will probably be in the mid 40's or so I'd also like to get feedback on what to change it to from what I have now for this condition. I have ordered a 170, 172 and 175 main jet and a 42 slow jet to prepare for the coming ride.