07 YZ450 starting issue(HELP!!)

2 replies to this topic
  • danimal95

Posted January 06, 2012 - 06:50 AM


Ive got an 07 YZ450 that has gotten progressively harder to start over the last couple months,heres the situation:

the bike is stock other than a full FMF 4.1 Ti exhaust and a no toil filter,used to start on the 1st to 3rd kick in weather weather ,and in cold weather it would start with 2 pumps of the throttle and full choke in 2 kicks no matter how cold it was out.The valves have been checked and adjusted every 20 hours and the oil changed every 5-10 hours depending on riding conditions,spark plug changed every 20 hours as well.

recently the bike has been getting harder and harder st start,it will back fire through the exhaust several times before it actually starts,no matter what process i go through to start it.I cant remember the exact timing but the only thing that may have changed since this problem started was at the end of my (car)race season I had some left over 110 fuel,so I started to run that through the bike,would have been bad by the time spring came around so I wanted to use it up.Is it possible the fule is causeing the situation?I am going to drain the carb and the tank tonight and put some fresh 93 in it,but I really dont think that is the problem.It should be said that I am a mechanic by trade so I have a good understanding of engines,any help would be appreciated

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  • grayracer513

Posted January 06, 2012 - 07:13 AM


Try the fuel first. If that's not it, check the stator.

  • danimal95

Posted January 06, 2012 - 09:08 AM


is the stator a common issue with these bikes?only 50 hours on it would be dis-appointing

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