Hi I have a 2010 gasgas 300 which is running hot and by that I mean after running bike from cold for about 5 mins the head is too hot to touch I have checked the coolant and topped it up but still hot

I have been told it could be woodruff key? Could it be this?

Any help would be much appreciated thanks

Chris, recently had the same with my 280 Pro resulting in the bike seizing and a costly bill for repairs. In my case it was the water pump that had failed, not sure if you are familiar with how this operates but basically the plastic impellor had stripped its left hand thread and was not turning with the shaft and therefore not circulating the coolant. A repair kit is available for about £70-£80 or the complete unit is about £150. Just to let you know I could not find fault with my pump until it was stripped down.

Hope this helps and you fix it soon.

Duffers.

Edited July 29, 201313 yr by duffers

thanks for reply duffers I have stripped water pump down and its all in tacked and turning correctly will pull flywheel tomorrow and have a look at wood ruff key

Hi I have a 2010 gasgas 300 which is running hot and by that I mean after running bike from cold for about 5 mins the head is too hot to touch I have checked the coolant and topped it up but still hot

I have been told it could be woodruff key? Could it be this?

Any help would be much appreciated thanks

The head should normally be too hot to touch, the surface temp usually is around 150-170 F. from my experience. It has coolant running through it and usually is the hottest outside temp part other than the exhaust system.. Do you have any other symptoms?

Jon

hi Jon i have a few other symptoms these are

1 the bike wont run right feels like the piston is catching the cylinder

2 the foam under the engine has begun to melt

i have pulled flywheel and woodruff key is intact

Running it to lean could cause overheating.

hi Jon i have a few other symptoms these are

1 the bike wont run right feels like the piston is catching the cylinder

2 the foam under the engine has begun to melt

i have pulled flywheel and woodruff key is intact

I'd check the jetting in the carb first. What jets and needle/needle setting do you have in the carb and what type of carb is it, Dellorto or Keihin?

Did you buy this bike new or second-hand?

The "melting foam" (I assume you mean the formed rubber insulators) symptom is interesting. The lower half of the engine usually runs cooler than the upper half.

Jon

Is the fan running? If not it could be the thermo switch (I believe the 2010 have it in the coolant line) If the fan is not running then to test the thermo switch just unplug the wires from it and take another length of wire to connect them directly to themselves. doing this should make the fan run constantly.

hi sorted bike by putting a hose pipe on the radiator hoses and flushed the head/ radiator out

sounds like some sort of blockage got flushed out.

Glad it's all sorted

would be very interesting to see the artifacts that you flushed out, hopefully whatever it was, didnt go through waterpump and tear that plastic impeller up? Be thorough, wash out hoses and pump while you were there, I hope.