'07 450 dies when hot


10 replies to this topic
  • rockieman

Posted June 29, 2011 - 08:27 PM

#1

Have an '07 450 that dies after the bike gets hot. I have an aftermarket stator to drive the head and tail light. After the bike cools down I can start it and run it again until it gets hot. It does not hestate sputter or anything while its running which leads me to believe its electrical. My first thought it was the aftermarket stator that I have maybe 20-30 hours on a rewind. After putting the OEM stator on ....the bike went through the same symptoms, started right up, ran great.....died after it got hot. After this happened I checked the valves which were all on the "loose" side (.15 and .25).
Tomorrow I'm going to trouble shoot the electrical back from the plug.
Anything else I need to check?
Thanks

  • brentn

Posted June 29, 2011 - 09:11 PM

#2

Just to make sure that it is electrical, does it bog when you give it gas but still idles then dies? Or does it just die straight up?

To rule out the kill switch, you never know, disconnect it and see if she still stalls.

  • rockieman

Posted June 30, 2011 - 05:07 AM

#3

Yea it just dies......as if the plug wire disconnected. It also acts as if there is "no spark" when I kick it after dying. After I let it cool down, it starts back up.
I'll give the kill switch a try....hoping it's something that simple and cheap.

  • rockieman

Posted July 02, 2011 - 12:42 PM

#4

Diagnosing my problem here..... should I start at the connection coming off the stator? And work my way out to the plug. The bike runs great for about 30 minutes, after it gets
warmed up it starts to bog, wants to die and eventually does.

  • grayracer513

Posted July 02, 2011 - 01:39 PM

#5

Next time that happens, loosen the gas cap before it dies and see if it clears up.

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  • rockieman

Posted July 02, 2011 - 03:17 PM

#6

I did try that ....doesn't appear to be vapor lock. The challenge in testing the stator, coil ect.... is once it cools off, everything checks out...and the bike starts.

  • rockieman

Posted July 02, 2011 - 03:20 PM

#7

I tried a different stator.....wondering if I should buy a new CDI, harness and coil. Looks
like I can get a used one for $75. That might be cheaper then taking it to a dealer to fix.

  • rockieman

Posted July 04, 2011 - 12:47 PM

#8

Just short of brain damage here :ride: I've checked and rechecked everything electrically. Here are the readings on the coil, cdi and tps and what the manual provides as the specification.

Primary coil: .1 with the ohmeter set at 200 .08~.1 ohms
Secondary coil: 5.73 with the meter set at 20K 4.6~6.8K ohms

CDI pick up coil resistance: .292 at 2K setting 248~372 ohms
CDI source coil 1 resistance: .871 at 2K setting 720~1080 ohms
CDI source coil 2 resistance: 54.2 at 200 setting 44~66 ohms

TPS coil resistance: 4.36 at 20K setting 4~6K ohms
TPS variable coil resistance: closed .44 at 20K setting 0~2K Ohms

Both the kill switch and the neutral switch check okay as well.

Am I wrong in being adamant that my problem is electrical :thumbsup:
I checked all these readings when the bike got hot and started to act up. What I wonder is all the specifications given by the manual are at 68 degrees, do these figures change when at operating temperature?

Any input is appreciated as I am this close to scheduling a visit with the dealer for them to figure it out.
Thanks

  • grayracer513

Posted July 04, 2011 - 01:27 PM

#9

The bike runs great for about 30 minutes, after it gets warmed up it starts to bog, wants to die and eventually does.


Am I wrong in being adamant that my problem is electrical :thumbsup:

I think so, but you could have a faulty CDI.

I checked all these readings when the bike got hot and started to act up. What I wonder is all the specifications given by the manual are at 68 degrees, do these figures change when at operating temperature?

Yes, heat in metal conductors increases resistance. 68 ℉ is an electrical testing standard.

My problem with the assumption that it's electrical is the part of your symptom description in bold. Electrical faults normally are more on/off in nature, rather than fading/bogging. Normally, fuel related problems would act like that. Something that would have a variable output and an effect on timing could do that though. It's a bit of a stretch, but maybe try disconnecting the TPS next time the bike acts up.

  • rockieman

Posted July 04, 2011 - 07:08 PM

#10

Thanks for the reply Gray....I think I'll need to do another diagnostic ride. The last time out it behaved a little differently then previously. Instead of just dying it would run erratic and eventually die. It also would start right back up after dying. I also noticed that one of the wires (brown) coming off the magneto had exposed copper as it goes into the plug. Can't think that would be causing this....especially after I swapped stators.
I'll also give a shot at unplugging the TPS.
Thanks again:thumbsup:

  • rockieman

Posted July 09, 2011 - 03:52 PM

#11

Bought (eBay) a slightly used CDI unit and Coil.....turns out my coil was what was causing the problem. Put the new coil in after it was already hot....ran the bike for about an hour and it ran great.





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