Overheating Indicators?

Another newbie question please. How do you know when your engine is running too hot? I've seen my radiator boil over (into the overflow tank) a couple of times and managed to get it to cool down right away but am curious if there is something I should be watching for that would indicate it's getting warm at an earlier stage. Any expert advice on this? Is a temp gauge available? Thanks again.


The one and only time I overheated mine was when I was stuck at the bottom of a hill, on a very hot day, with a lot of wheelspin and no movement. The bike started to actually puke steam out the overflow tube on the bottom of the bike. After I got moving though it cooled off instantly.

It'll put a little coolant into the overflow reservoir normally. That's part of it. If it's overheating you'll smell it and probably see it. It'll also start actually bubbling into the reservoir.

yeah the same thing happened to me, was very hot, and i got stuck on a hill full of roots and ruts. it puked some out the overflow jug, but cooled down as soon as i got moving. i just added some to it and it was fine. evidently it doesnt take much air through the radiator to keep it cool, because most of my riding is on slow tight trails, and that is the only time i have noticed it boiling over.

Last summer on a very warm day, I rode up a very wet rocky creek, stalled the bike a number of times and had a lot of wheel spin. As the motor got hot it spilled coolant into the overflow tank. Towards the end of the creek, whenever I would pull in the clutch and back off the gas, the engine would stall. Thank goodness for the e button. As soon as it cooled down, it would idle fine with the clutch pulled in.

I know mine is running warm when in really slow stuff and I've stalled it a couple times... when pulling in the clutch and cranking then beginning to move out, it'll conk out and then take a couple of good spins of the starter to fire back up again.

I've never seen steam come from the rad cap, but I've noticed some coolant in the overflow tank before, not much, maybe a few ounces. Once going again, the bike cools off quick and pulls the overflow juices back into the main cooling system.

I think adding any kind of Rad guards, like the devols or thumper racing guards decreases the radiators ability to dissipate heat. Number one, your taking off the directional "vents" inside the scoops which sort of force air through the veins, and number 2 your putting something over the face of the radiator - whether it has a bunch of holes in it or not, I think it must have some effect on the radiators ability to transfer heat effectively.

My $.02

Hollywood :)

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