mine has hit redline a few times after hard riding and then sudden slow down..
as long as the fan is running, even in hot weather, it shouldnt over heat. and will cool down after a few mins

if it does overheat, it might blow out some coolant on the ground from the overflow hose below the bike..

i dont beleive any vehicle will shut right off if over heated.. (unless you keep driving/riding it till it blows up)

if over heated, a few mins rest will usually be sufficient for it too cool off for riding again.. but if it does actually overheat, i wouldnt want to be riding it too much without finding out why its overheating.

-Jeremy

 

If it overheats and the fan doesn't work or you can't get airflow by moving you should shut that sucker down. The engine can suffer serious damage without liquid cooling. If the engine is running close to redline all the time you need to check out the cooling system and find out why. A mechanic at the dealer I bought mine from told me that those "cooling fins" are purely for looks and will not cool the engine if the liquid cooling stops working.

 

I'm sure other experts can chime in with more accurate details and blast this hypothosis all to crep...

when the engine overheats, the valves and head start to warp. They may warp enough to cause structural failure and crack. A valve may drop and get slammed by the piston...

Pistons may get too hot and start to wear away, leaving metal streaks on the cyclinder walls and gouges on the pistons.

The bearings will do about the same, wear and loose metal, and I'm sure a bunch more parts will do about the same...

That's about what happened to my engine...it just started running sluggish and loss of power, but kept running. It got a knock, but kept going, until it finally dropped the valve and really started making some noise with great loss of power.

Still, it had enough to just barely run at 1/2 throttle and if you milked it, you could get it to drive about 20mph max. Eventually, yeah, it just turned off...

 

If it really overheats and you're lucky, you'll blow the head gasket and spray boiling coolant and steam everywhere. If you're not lucky (keep in mind luck here is relevant, skin does eventually grow back.....), the gasket blows INTERNALLY, mixing the boiling coolant with the oil. Now you have a bike that's not only too hot and warping the heads, cylinders, etc., but now the oil is turning into this foamy mess that's just a little better than dishwater for lubrication, so your bearings and mains start scoring and cooking.

That's why if it touches the red or the light flickers on but the fan kicks on, you're probably okay. If the needle buries in the red or the light doesn't go off, pull over and kill it before it turns into a "time for a new bike" nightmare.

And yeah, the cooling fins help, but that's all they're designed to do, HELP. Not gonna do much good once there's no coolant circulating around in there.