Jul 27, 1999
I boiled out all the coolant a couple of weeks ago at a low speed hare scrambles on my 99 300EXC. So I'm wanting to remove the thermostat to increase flow. Can I just remove the thermostat from the housing, or does something need to take it's place? Will the hosing seal if it is empty.

By the way, I'm removing my Devol guards changing to "Blue Ice" (or what ever it is my dealer sold me instead of water wetter) and checking my jetting. I know I was way lean on the pilot screw.


Dec 31, 2000
Devol guards

Do you know if those Devols will fit a 200 300exc? If they will and you are interested in getting rid of them I may be interested.

Idaho Charley

Jul 20, 2000
You can remove the thermostate but will need to put in a spacer to allow the housing to seal. A suitably sized washer will allow the housing to seal on the o-rings. There has been discussions in the pass focusing around whether or not you need to restrict the flow somewhat to prevent cavitation/circulation problems associated with turburlent flows and also the need for extended warm-up times. I did take mine out last year for awhile last year for awhile and did not have any problems.


May 4, 2000
I have run my 99 300EXC both with and without the thermostat, and found there to be no discernable difference in cooling efficiency either way. I have now reinstalled it because I ride in cold temps occasionally. I have just come to grips with the fact that my 300 is going to run hot once and awhile. On those slow hills where the bike is most likely to heat I just leave it in first gear [to prevent lugging the engine] and stay away from the clutch until absolutely necessary.

Murf, I have a brand new set of Devol radiator guards for the 300 if you are interested. I will find out if they fit the '00 model. They would not fit my alreadly bent radiators.

Welcome to DRN

No trolls, no cliques, no spam & newb friendly. Do it.


Top Bottom