hooth4 wrote on 07/13/12 at 08:27:06:I didn't understand about the jets
I don't know how much you do/don't know about jets, so here is a primer (my apologies if it is too basic for you):
Jets are little brass inserts in your carb of different sizes that allow more or less fuel to flow with the air into your cylinder. On the stock carb there are three jets: pilot (idle circuit), needle jet (mid range), and main jet (wide open throttle). Keep in mind these three circuits aren't entirely independent of each other. In addition, the stock carbs have an air mixture screw that affects the idle circuit, allowing you to fine tune the air/fuel mixture at low throttle ranges.
Anyways, if your idle jet is too small, and doesn't allow enough fuel to flow with the air, your engine will run lean (more air than fuel than is ideal) and lean means hot.
If you say the shop adjusted/cleaned your carb, you might want to look into tuning the carb yourself. Serowbot has some great tutorials on how to do this, so I won't get into it (look in the Tech section!). But if you are feeling a little DIY, take a screwdriver (if the air mixture screw is exposed (ask if it is not!)) and turn it in/out to get the best idle, and that will get you to a better idle mixture point.
Idle circuit aside, other circuits can be lean causing overheating, too. That is less common because you'd have to be moving to be using those circuits so your engine would be getting *some* cooling, but I digress...