I ride the desert no more than 3000 ft high mostly around 2000 feet high but I live at sea level.. It is quite warm here even now 'autumn', the max temps are around 95-100 and the minimums are around 75 degrees fahrenheit.. My 05 YZ450 is only a couple of months old.. Usually she starts straight up.. but today when I changed oil and cleaned the filter I couldn't start it to check the dip stick.. For the first time since I got the bike, I washed the filter with some gasoline before putting the foam oil on.. (I usually wash with warm soapy water but I didn't have it with me so being lazy I just used what was handy).. I left the bike for several hours and it started up pretty easily after sitting so I figure the gasolene on the filter was making it too rich .. The choke was useless and it would only start with the hot starter pulled.. It runs hot though I mean we're talking red glowing header which I know is normal but I think leaner means hotter doesn't it? I am inclined to think it is OK for riding but I am interested in any opinions as I am still a bit of a newbee.. So is it bad to wash the air filter with gasolene? As I have to use the hot start even on a cold bike is it set a bit rich?