I just bought a 92 300 with 1000kms or 600 miles.....The bike is show room cond,only used to plow the driveway,It was sitting or a few years and was quite gummed up,I got that solved,but it doesn't seem to idle right ,iThe idle goes up and down by itself,maybe a sticky cable? 2nd problem is, The header pipe heats up really fast and becomes beat red...Is there any reason for these two issues,any help would be great.

 

Sounds like its too lean, look for intake leaks, and if you dont find any, the mixture screw may be too lean, or the pilot jet is still partially plugged.
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