2012 wr450 starting problems after overheating

My 450 has always ran and started perfectly. One or two pushes of the electric start and it always fires up, know matter what the temp. FMF Powercore and ecu are the only engine upgrades. I have owned this bike since new.

Last week in 30 degree temps I didn't realize my friend put a footpeg through my radiator and I rode for a couple, to a few more hours before I noticed. Guys behind me smelt oil while I was in 5th gear open, that's how I discovered the hole. After changing the radiator, I did an oil change. About 3 oz of oil came out of the bike, OUCH!

Did a fresh oil change/filter, and the bike appears to idle and run fine. I had to test in snow with spikes but it seems to run fine. Here's the problem, it doesn't start right up anymore. Have to try all different methods to start: cold start button/ holding throttle slightly open/ battery charger all these seem to help get it started but no definitive start. Kicking does not help and it seems to lock at TDC a lot when using the electric start. Any ideas?

Did the oil smell burnt? Does it have any/ similar power? I'd do a compression/leak down test and report back. Or just pull the motor and check cams and journals for wear/meltdown and your cylinder piston rings for scaring.

Not sure if the small amount of oil I removed smelled burnt, don't think so, but it certainly smelled from the exhaust which is how I realized something was wrong.  After I changed the radiator and oil, I went for a ride but it was with spikes in 3 inches of snow. the power seemed fine.  Tomorrow I will check compression and take it for another test ride for power loss. Maybe remap my ECU. With all the oil I burnt, do you think the packing In the FMF Powercore was affected? I assume my oil loss was out the exhaust.

I bet you burned a piston.

Tried finding the compression rating, and I found out you cannot do a valid comp test because off the auto decompression.  So a leak down test will have to be done. Will buy one Monday and do the test. In the mean time I put a full charge on the battery and it has started 1st push of the button 5x within a 48 hour period.

CHANGE YOUR PLUG !

 

Then pull the throttle body and make sure the sensors are not carbonized

Thought I was looking good after bike started so many times on the first press. well, it's not looking good. Haven't started the bike in a few days. Went to start it today and it would not start. Pulled the original  NGK CR8e and it was heavily black. changed it with a NGK CR8 iridium, cleaned the throttle body sensor and still no start. Did a compression test out of curiosity(auto-decompression) and it pinned at 30.  Tried to convert my compression tester into a leak down but I need an adaptor to make it work. Should have an adaptor at work. Plan on pushing 40lbs of air into the cylinder at TDC and listening for leaks via exhaust or head. Will do that by this weekend. I have a feeling I will be pulling the motor as "Guru" suggested.. Will keep you posted.

Edited by comp123

You can't do a peak compression test with an autodecomp motor....but 30 is very low. Should be double that.

 

Have you confiremed the FI system is working, but removing the injector and seeing if it sprays?

Swapped out the iridium plug and put  new CR8E and the bike fired up but very hard to start. once started it seems to run and idle OK. I don't think you can use an iridium plug on the WR.. Hopefully I get the leak test done tonight.

Swapped out the iridium plug and put  new CR8E and the bike fired up but very hard to start. once started it seems to run and idle OK. I don't think you can use an iridium plug on the WR.. Hopefully I get the leak test done tonight.

 

I have been running iridium plugs without any issues on my 2012 WR.

Iridium isn't 'different', it just lasts longer.

Just put 40 lbs of pressure into the cyl at TDC and there are no leaks.  Took the bike for a ride and it runs great. WTF. It is just incredibly hard to start. Before this problem , if the Estart didn't start bike, one or two kicks would start it up. I kick the hell out of it now and it never starts. It seems to start the best on a fully charged battery. Battery is less than 2 old and tests fine.    When I cleaned what I assume is the throttle body sensor, I removed the cover held on by 2) T25 torx. I was then able to see the throttle action behind the cover so I cleaned that whole area. Is that the Throttle body sensor I should clean? Other than that I will be pulling the motor. Is there any way to do an accurate compression test before l pull the motor?

It won't be terribly "accurate" but testing compression for a baseline then squirting motor oil in cylinder and retesting may give you a clue. If the # goes up significantly with oil then you are loosing compression past piston/rings. The leak down result you got says to me that your valves are good. You could also check that your valves are in spec. That's great news.

I still think low compression is why it is so hard to start. Good luck.

Did you pull the TPS

It exposes a shaft connected to the butterfly.

If you did, you messed up, and will have to re-calibrate it.

There is a MAP and TEMP sensor in the throttle body (or airbox, can't remember) that you clean the harnesses and add contact enhancer, and  clean the sensors (no strong solvents).

 

Hard to start but runs well (idles steady, no flame out, etc) means your mapping is off, your TPS is off, or your meter knob (idle) is set too low.

 

I would bet that your TPS  is the issue. 

 

Get a service manual, spec check it.

Just put 40 lbs of pressure into the cyl at TDC and there are no leaks.  Took the bike for a ride and it runs great. &%$#@!. It is just incredibly hard to start. Before this problem , if the Estart didn't start bike, one or two kicks would start it up. I kick the hell out of it now and it never starts. It seems to start the best on a fully charged battery. Battery is less than 2 old and tests fine.    When I cleaned what I assume is the throttle body sensor, I removed the cover held on by 2) T25 torx. I was then able to see the throttle action behind the cover so I cleaned that whole area. Is that the Throttle body sensor I should clean? Other than that I will be pulling the motor. Is there any way to do an accurate compression test before l pull the motor?

Did you check your valves?

Edited by RRM707

Thanks for posting this video for me Rick. This shows my starting woes. Took this Vid today.

Well hell, it's freezing out, you have to re map for conditions that extreme

 

Have you tried advancing your TPS a few degrees, and turning up your idle?

Before I pull the head I am going to try a couple more things. Put my stock ECU in, and or, remap my COMP ECU.  If you have a mapping suggestions I could use advice. Right now I am on the FMF Powercore mapping  recommended by GYTR. Also want to find the sensors in the throttle body and clean them.

I don't think you have any mechanical problems

I believe your problem is trying to start a motor in sub 40 degrees without pullin the fast idle knob, which it is not designed to do without modifications

Have you adjusted your idle higher 

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