2009 crf 450 getting hot and shutting down

Hello everyone,


I have an 2009 crf 450 and im having an issue with it getting hot and shutting off. It will only do it when im racing.I can practice and practice and the light will not come on and it will not shut off. I can see the light flashing when im racing when i glance down and once if flashes for a few mins it will shut down and will not restart untill it cools down. i cant stop to count the light flashes on the bar to get the code when im racing. ive tried everything with keeping it cool.i know its hot...it is a heat issue. im not pushing coolant out because im running evans coolant and the bike shuts off before it boils. im not sure if the coil is cutting out or if its a sensor going out. its done it to me now in 3 races now im fed up with it. it runs great no missing no cutting out nothing.. im going to test the sensor in the cylinder tomorrow. any other ideas??   



Sorry i should have noted my type of riding, Gncc and offroad racing.. about an 45mins to an hour into the race it starts flashing..

Take off your radiator cap while running and see if you can see the water churning. If not, your water pump impeller is going bad.

If you have stock mapping, you are running lean on the top and rich on the bottom, and that needs to be corrected.

I just replaced the water pump seals, saft and bearing i know its working good. i also have a vortex ecu i have it set richer than stock on low mid and high adjustments. thats what the paper say any how.. any other ideas??

It has to be electrical, and is probably the CDI. Try packing it in dry ice and see if you get more time.

Evans straight waterless coolant ran 10-15f hotter on the gauge (but didn't boil)  on a turbo'd suburu motor we put in a veri ez .   Could be your coolant temp is running outside the parameter of your computer?  Did you have this trouble with a 50/50 coolant?

Krannie- Im with you It has to be electrical. I ordered the the heat/water temp sensor that goes in the head. it is a cheap easy part that hey if its not owell .i got my money out of it and have a spare. I also made some calls today and got some feed back about the maps I have on the vortex. they are more MX/Supercross set up. im having it remapped with a more "off road" type set up hoping that it will help a ton by the way it sounds.


Highmarker- "Could be your coolant temp is running outside the parameter of your computer?"
You hit the nail on the head. the reason im running evans is because ive had trouble with engine ice and 50/50 boiling out and if i lose any it just never cools back down. It seems to be better if i keep all the coolant in and get out in the open and get it cooled off.



Im thinking its the maps but im going to test the head sensor and check just for fun so i know for sure.. ill keep you guys posted on the sensor.

ok i tested the ect sensor and its working just fine. i hope the remap does the trick. hope to have the ecu next week sometime.

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