Colder weather

2 replies to this topic
  • Yz400f Jeff

Posted November 14, 2013 - 05:11 PM


The yz400f had a hard time starting up the last couple of times out. In the summer months it's started first kick hot or cold thats was anywhere upto 110 degrees. Now that it's in the negatives and single digits it won't go without 1 or 2 twists of the throttle and stalls a couple times before staying lit. I will probably be riding all winter in negative double digits. Should I move the needle up a clip?? I'm sure I have big enough jets in already 48 65 and 180 main I believe my fuel screw is out 2 turns maybe 2.5. Maybe my oil is abit to thick? I have fresh rotella 15/40 in now, just started running it afew hours ago seems great so far switching from amsoil 20/50 it was to rich for my blood.

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  • grayracer513

Posted November 15, 2013 - 08:14 AM


Not the needle, no.  Go to another step larger pilot, or perhaps better, a number 70-72 starter jet, if the "65" is for that one.

  • Yz400f Jeff

Posted November 15, 2013 - 08:44 AM


Sounds good I'll put in a 50 pilot and 70 starter for the winter. Should I cover up one of my rads on the really cold days and get some 10w oil also??

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