Yz450f blowin smoke....

8 replies to this topic
  • DoctorRzed

Posted June 11, 2005 - 09:42 AM


I left my bike outside for the past week while I finished up the garage. All week it has been raining and temp around 80. Today I went to start it and it would not start. Would not even attempt. Usually it takes bout 2 kicks. I removed my air filter and noticed some condensation in the boot. About 40 kicks later I started it. However it was burning oil for about 3 min. I let it run and it went away. Never smoked before on startup. Could this had been because it was left outdoors???
Or should I tear it down?

  • John_Lorenz

Posted June 11, 2005 - 09:46 AM


Bad news, you have to tear it down and rebuild it

  • curtains23

Posted June 11, 2005 - 09:49 AM


Leave it alone and see what happens the next few times you run it, as an indicator
to give you an idea blue smoke is oil, black is too much fuel(flooded) I would suspect it has been flooded by the ammount of kicking required but time will tell, Good Luck

  • DoctorRzed

Posted June 11, 2005 - 09:55 AM


Yeah some black smoke. I rode it no loss of power no loss of compression. Let it sit for a few hrs started no problem w/no smoke???

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  • 99wr400

Posted June 11, 2005 - 09:58 AM


It was probably steam from the condensation in your engine. If not, Your valve seals may be worn out, and then you will find out that they wore out because your valve guides wore out, and you will get to pay around (I payed $475 with a huge discount for my WR head to be rebuilt) $500+ to have your head rebuilt. While you have the head off, might as well check out the piston and rings, if they are out of spec. replace them. If the cylinder is out of specifications, have it bored over so you can save your money from buying a new cylinder. If it smokes more at high throttle positions, and a lot at start up, its probably a valve seal.

  • 99wr400

Posted June 11, 2005 - 10:00 AM


Yeah some black smoke. I rode it no loss of power no loss of compression. Let it sit for a few hrs started no problem w/no smoke???

You got lucky. Sounds like you just flooded it.

  • DoctorRzed

Posted June 11, 2005 - 11:28 AM


Yeah It must have been condensation but I could of swore it had a hint of blue but it could of just looked like that because of it was flooded. Come to think of it I washed it last week and never bothered to start it. Ill let it sit a couple of days and start it again, If its the valve seals I sure thats enough time to see if it leaks.

  • crf450f

Posted June 16, 2005 - 09:00 AM


Do not leave it outside next time!!!!!!!!!!!!!!

  • mxaction

Posted June 16, 2005 - 03:16 PM


if it was windy while the rain was coming down and you had no plug in your exhaust, then bad news. sounds like way to much water got into your engine. rebuild it.

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