2000 WR400 Smells hot....is that normal

I'm new to the WR400 so I know nothing. If I leave the bike running in the garage for 20 minutes or so, when I come back to it it smells really hot...like something is burning. The coolant tank is very audible with boiling water/coolant and a mixture of coolant and oil has leaked on the garage floor from the plastic tubes at the bottom of the bike. Is that normal? I also notice this when riding hard (hard as in high rpm's). Should I be worried or write it off as normal operating procedure?

You really shouldn't leave it running that long with no airflow through the radiators :prof: The rads need air moving through them to effectively cool the engine.

I've never had mine overheat from haulin' ass, but high load-low speed stuff will do it....

Is that true even with liquid cooled engines? I know that this was the case with my Honda 400ex....but this bike is liquid cooled. Does that still ring true? Again my concern is that it smells hot even when riding it at high rpm's....but then again that's usually when hill climbing or other activities where I'm not going very fast....so there's not much air going through the radiator. Does that still sound like not enough air?

With proper jetting you ought to be able to keep it from boiling over while riding unless you crawling around in really hot weather. I also wouldn't ever idle it for more than a couple minutes (about the time it takes me to put on my boots and helmet.)

That said, even when my bike is running great it has a distinct smell. It's sort of a mix of burning coolant and rubber, and I can smell it slightly whether the bike just got started and immediately turned off or I've burned a half tank without stopping. Hope that explains something.

Yes it's liquid cooled, but has no engine mounted fan, or aux. fan. That would keep air moving even at a stand-still. It relies solely on the air moving through as you ride, to cool it. That being said, I've never boiled mine over, and ride extremely technical trails. I haven't let it sit and idle that long, so don't know how it would react to that. I do run Engine Ice to keep the temp down.....

Have a WR450 which will also overheat if left running whilst standing. Like husqvarnarider said, your bike has no fan so relies on air flow through the rad to reduce engine temp. I definitely wouldn't let it idle for 20 mins. The coolant or expansion tank will bubble and fill up as the water expands. It will do this before chucking it out of its overflow pipe. Again it's not recommended to let this happen. It probably does smell of burning as the engine is so hot it is possibly scorching something in close proximity to it - cables / electrics / plastics. If it runs hot on the trails, it may be worth checking your jetting and fuel mixture. Running a bike too lean will cause it overheat prematurely.

Just in case you didn't get it the first three times: don't let your bike sit and idle for 20 minutes! Liquid cooled or not, it has no fan like a car to cool it while standing still.

Check all around the exhaust for anything that might be sitting against it that shouldn't be. Also, check around the cylinder, particularly at the front of the motor - maybe you're leaking a bit of oil or coolant onto the header.

That all makes sense. Thanks for everyones help.

Also check to see that the water pump isn't leaking slightly at the weep hole , some of the WR's have problems with the water pump shaft and seal. Checking it is free. Has the reservoir been removed? Do you have to add coolant constantly? Is the oil a bit milky? No need at this point to mention that the idle time is approx. 15 minutes too long. :prof: WR Dave.

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