2004 Yamaha TT-R 125 L Logo
Posted on Jul 08, 2009
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Hard start cold

From the day at the dealer in 04 this bike has been hard to start cold! hot It start great. It will only start cold if the choke is on with starting fluid then only run for a few seconds then die. Do that 8 or 10 times then have a great day riding. The problem has gradualy become worse over time. I have been through the carb several times. It has always run lean so I went a little biger with the main jet. didnt help. spark is always good. I have checked valve lash and checked compresion.Any help would be great thanks.

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Murtaza Akberali Versi

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  • Yamaha Master 767 Answers
  • Posted on Jul 08, 2009
Murtaza Akberali  Versi
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Joined: Jan 31, 2009
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You will have to check the float level of the carburator, try too, to blow out with compressed air the primary jet.
You will also have to reset the air-mixture screw and its better to have it a little on the rich side.
Also check the spark plug gap.
Hope this helps!

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