2012 WR450 Baja Designs kitted died in the heat. Vapor lock?

Yesterday I road a single track trail that was new to me.   That trail should be marked for trials bikes.  I spent very little of the 25 minutes on that trail out of first gear.  The air temp was about 90.  I stalled just before getting to an open area where I could pick up speed.  I could hear the coolant boiling, but the sound stopped after about 45 seconds.  So I pushed on to the open area where the wind was blowing good and I could get into 3rd gear.  About a half hour later I was on a gravel road obeying the 25 MPH limit when the motor died.  The starter motor showed no life but the lights and horn worked.  At this time the motor was not making any kind of boiling sound, and when it was running sounded good.  After 5 to 10 minutes of sitting on the side of the road I turned on the key and heard the fuel pump.  I hit the fuel pump and the engine fired.  I road back to my pickup.

 

I've had this Baja Designs kit on for a couple of weeks and have been riding it a few times around town.  Now I don't feel so good about riding in the back country because I always ride alone.

 

Any suggestions on what I should do next?

What BD kit are you talking about? A lighting kit? I don't see how a lighting kit is causing your problems.

I would make sure the fuel tank is venting properly. If you have one of those stubby vents valve things on your fuel cap, ditch it.

Are you running a coolant additive like Water Wetter? If not, you should be.

It's the Baja Designs dual sport kit.  I changed the coolant to WaterWetter, antifreez, and water.  Took the vent off.  Bike warms up rides for 2 or 3 minutes and quits.  It has a fresh tank of fuel.   If it quits going downhill I tried bump starting.  It turns over won't run.  Let it cool off for 15 minutes and it runs.

 

Any suggestions on what is wrong here.

 

Thank you, Doug

Have you changed the ECU and mapping.  How about the CO level?  These bikes are ridiculously lean from the factory.

Do you have a suggestion on ECU setting?  Not sure how to mess with the CO level.

Yes, FMF map or MX map - richens the mixture and runs cooler.

The throttle body has a temp sensor that can shut off the ECU, and can also fail.

All the above. I once had a similar problem which turned out to be a bad stator. I'm curious as to whether your stator was modified for the Baja Designs kit.

It's the Baja Designs dual sport kit.  I changed the coolant to WaterWetter, antifreez, and water.  Took the vent off.  Bike warms up rides for 2 or 3 minutes and quits.  It has a fresh tank of fuel.   If it quits going downhill I tried bump starting.  It turns over won't run.  Let it cool off for 15 minutes and it runs.

 

Any suggestions on what is wrong here.

 

Thank you, Doug

 

He's eliminated the cap vent as a problem. It's starts from cold, runs a couple minutes then dies. Wont bump start.

 

I'm familiar with the BD kit, I think that's not it.

 

Reads like a fuel vapor lock. Pinched hose?  The Tank to FI Body hose is kinda long, and if the tank is not set down correctly, it will pinch hoses. But, this first occured after a long operating time, so... prolly not that.

 

Fuel pump or power?  Blocked fuel filter?  You can check for correct fuel pressure to the FI Body.

 

Weak / Near Dead battery, or charging system? Break out the volt meter and measure the charging voltage.

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