Yz 426 runing to rich ???

3 replies to this topic
  • kubamtx

Posted August 19, 2007 - 01:51 PM


My bike always started better with hot-start when hot/warm (not after crash...). Today I saw few more things. End of my exhaust is black after few rides and my bike is killing the plugs, not during a ride but after, when I'm going to start it next day, usually changing plug helps.

Please tell me if these are common problems when bike is running to rich?

  • Ga426owner

Posted August 19, 2007 - 01:55 PM


yes way way too rich....
what is your jetting?
needle clip

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  • kubamtx

Posted August 19, 2007 - 02:16 PM


I'll check my jetting tomorrow now I've got night in Poland;-)
The previous owner said that it has factory jetting.
I ride 200m over see level and humidity 75-80% and temperature over 24 degrees Celcius.
I'll check the jetting and we'll see.

  • kubamtx

Posted August 21, 2007 - 01:54 PM


I've checked my jetting today and I think I found the problem.

MJ: 162
PJ: 42
needle: 4
Which is ok for 700 ft, 80 F.

But mu fuel screw was 1 3/4 turn out and manual says that it should be 1 1/4 turn out, is this a problem?
Do I found the problem or fuel screw is not responsible for my problems?

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