1993 Suzuki kingquad 300 over heating

[butlerbuilt]

I have a 93 kingquad that I need help with. It over heats and cant figure out why and hoping some one here can help me. Have stuck a few bucks into it and no change. Put the new right jets in it. Exaused rocker. Head gasket. New boot. It runs real nice and drives but after 15 minutes of run time the exuast gets red. I am stuck and dont know where to turn. Hoping someone here has some advise for me. Any thing you can tell me would be great. THanks

[DirtDemon]

What does your spark plug look like? A lean condition is a likey cause. If you are running lean you may need larger jets. Many factors can effect jetting requirements, elevation, temperature, motor mods..... You need to read the plug to determine wheather you are jetted properly. There are other factors that can effect jetting requirements too. Make sure the carb is clean. Check for air leaks in the intake plumbing, if you are sucking in extra air it will run lean and hot. Check the fuel screw adjustment. Check the timing chain and tensioner. Check the valvle lash. Check the oil pump and oil cooler lines.

[Ajmboy]

Lean condition....just like DD said.

[butlerbuilt]

Hey thanks guys. I have been thinking and tell me if I am off. Not knowing the history is it possible someone put in a bigger piston and the jets that are called out for are not right. And if the timming is aff a bit would it still run and idle good but still get hot? Thanks

[DirtDemon]

Timing could be an issue, it is worth checking. Going up one or two sizes on the piston will have little to no effect on performance or jetting needs. You need to increase bore size by several mm to make a significant difference, most piston replacements are done .5mm at a time. Google "plug chop" reading the plug is the best way to determine correct jetting. Check everything I mentioned in my first reply. If you have a lean condition, due to an air leak, dirty carb, incorrect jetting or adjustment, you could burn your motor up in no time.