'09 450 Hard to Start When Hot


7 replies to this topic
  • buzzfin

Posted April 21, 2009 - 07:34 PM

#1

I'm having a heck of a time starting my '09 450 when hot. I also get some popping on decel. Did lots of searching, but most of the threads are guys who have changed their pipe. My bike is completely stock (except for heavier flywheel) and it starts first or second kick when cold. Elevation here is between 500 and 1000 ft. Temps this time of year have been in the 70s. Should I concentrate on adjusting the fuel screw or do I need to change the pilot too?

  • gbalias

Posted April 21, 2009 - 09:42 PM

#2

how many turns out on the fuel screw are you now?

  • buzzfin

Posted April 22, 2009 - 05:22 AM

#3

Fuel screw is 1-3/4 turns out.

  • gbalias

Posted April 22, 2009 - 03:01 PM

#4

if its starting issue, id start with the pilot circuit. sounds lean to me based on your symptoms. have you followed the pilot circuit tuning procedure?

http://www.thumperta...ad.php?t=327405

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  • Kawirider37

Posted April 22, 2009 - 09:25 PM

#5

couldn't hurt to try turning the fuel screw out 1/4 to half a turn. try that first, then go from there. As long as you know where your start point is, you could always revert back.

  • TD-3

Posted April 23, 2009 - 03:24 AM

#6

If it starts good cold.....but not hot......I would say it is a rich condition. Some popping on decel is fine...IMO If you jet to rid a bike of decel pop, then it will more than likely be on the rich side.

buzzfin: Are you using the hotstart? Is it hard to start after it stalls, or all the time?

I tend to go leaner on the pilot (Rekluse likes it this way), which makes the bike less apt to stall in tight low speed conditions, and as a by product easy to start hot.

My 2 pennies.

  • buzzfin

Posted April 23, 2009 - 05:32 AM

#7

if its starting issue, id start with the pilot circuit. sounds lean to me based on your symptoms. have you followed the pilot circuit tuning procedure?


Haven't followed this procedure yet. Will try and see.

Are you using the hotstart? Is it hard to start after it stalls, or all the time?


Yes, I've tried both with and without the hot start. It's hard to start whenever it's hot - whether it has stalled or been shut down normally.

  • buzzfin

Posted April 28, 2009 - 01:04 PM

#8

Adjusted the fuel screw according to the pilot circuit tuning procedure:

http://www.thumperta....d.php?t=327405

Starting MUCH better when hot now and the decel pop is gone. Thanks guys!





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