I haven't had much experience with bikes, but do the GS's run hot?
Mine always seems a little hot after about a 10-15 min ride

I guess it depends by what you mean by hot.  Do you think it is running abnormally hot?  A GS is air cooled and the engine will be to hot to touch after a fairly short ride.  Thats normal.  If your melting your front fender with the heat your running to hot, check the oil, and check your plugs, if they're all white its lean, and will run hotter than normal.  

If it just seams a "little" hot your probably ok.

I've wondered this with both bikes I've owned.  Both bikes are air cooled, and with no temp gauge.

How do you know when an air cooled machine is too hot?

When an air-cooled bike overheats the rpm's go up.

So choke off, warmed up engine idles at about 1,000rpm.  If I was stuck in bumper to bumper traffic on a 98 degree day, if the engine speed started to creep up- that would be a sign of overheating?

First, you should set that "warmed up" idle speed a little higher.  The manual specifies 1200 RPM; I tend towards 1300.

Second (to answer your question) - Yes.  When I'm stuck in traffic (as in STOPPED) on a 95+ degree day I turn the bike off and wait for the jam to loosen up.  I was forced to do that several times per intersection last year while trying to get through a not-so-big burg named Kelowna in British Columbia last year.  The hill just south of town was putting off a huge mushroom cloud of smoke from the forest fire raging there, which just added to the feeling of HEAT....

I am not saying it overheats, but I cannot touch the engine, it is very hot.
So I was just wondering if that was normal.

I would assume that it is being air cooled

Thanks

Quote from: EvilScoobyI am not saying it overheats, but I cannot touch the engine, it is very hot.
So I was just wondering if that was normal.

Yep, quite normal.  If you can comfortably put your hand on the engine ... you must be wearing some pretty thick leather gloves!

If the engine really overheats, you should be able to detect a color change in the exhaust pipes, where they exit the engine block.  I think some folks have seen them turn a dull red!

As you probably already know, air-cooled engines are directly cooled by air flowing over the heat-dissipating ("cooling") fins on the engine block.  This cools the engine in two ways: by whisking heat away from the metal surfaces, and by indirectly cooling the oil underneath.

Water-cooled motorcycle engines (like those in cars) are also cooled by the air, but even more indirectly.  The air flows between the many THIN water passages in the radiator and whisks the majority of the heat away right there.  The cooled water circulates back through the engine block, where it more directly cools the metal and the oil.

Bottom line: Keep moving through the air, or turn off the engine if the bike is going to be motionless for a period of time!

(This is why you're encouraged to set up a large-ish fan to blow air past the engine while you synchronize the carbs.  Assuming you use the standard method that requires the engine to be running....)

awesome,
Thanks for the info guys