New to me 04 YZ450f

28 replies to this topic
  • jeffvian

Posted January 09, 2016 - 10:54 AM


Whoops double post

Edited by jeffvian, January 09, 2016 - 10:55 AM.

  • grayracer513

Posted January 09, 2016 - 01:10 PM


Have you tried a fresh plug?  If it's been through all of this, and it wasn't new to start with, it could be wet fouled. 

  • grayracer513

Posted January 09, 2016 - 01:18 PM


Since the bike is new to you, let me point out also that even though it has auto decompression, there is still a best procedure to follow.  To begin with, you need to learn NOT to twist the throttle as you start the bike.  When they are cold, they do like 1-3 twists of the throttle before you kick, but not while you're kicking.


Whether hot or cold, bring the kick starter down until you hit the compression stroke (the "hard spot") and stop.  Reset the kick starter back to the top and kick it smoothly all the way through the starter stroke.  Just kicking from random places doesn't work as well, and even worse is trying to out think the system by pushing just past TDC and compression.


'03/'04 models sometimes like a VERY SMALL amount of throttle when starting cold, but I mean very small, just off of idle, and be sure you're wearing good solid shoes.

  • jeffvian

Posted January 09, 2016 - 02:46 PM


I was just thinking it could be the plug. I give it one or two pumps usually. I dont mess with the throttle when im kicking but i do just usually kick from any random place. Ill try the new plug and those tips you gave me.

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  • jeffvian

Posted January 11, 2016 - 10:03 AM


Well tried a plug and still dont have anything at all. Ill see if i have spark and go from there.

  • jeffvian

Posted January 11, 2016 - 01:19 PM


And it seemed to kick over a lot tougher than it should even when i didnt have the spark plug in it

  • jeffvian

Posted January 15, 2016 - 08:34 AM


How hard does your bikes turnover when theres no spark plug in them

  • grayracer513

Posted January 15, 2016 - 10:29 AM


Not much resistance, and there should be no "catch points" or "tight spots". 

  • jeffvian

Posted February 28, 2016 - 07:37 PM


Well i i tore it apart and put it back together and i think one of the plastic cam chain slides wasnt in there right. It starts and runs great now. Thanks for the help.

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