2003 450f won't start

2 replies to this topic
  • Norcalyz

Posted November 26, 2011 - 04:46 PM


Background on the bike is I bought it from a guy who had it sitting in his garage for the last three years.

I brought it home and pulled the carb to clean it out and found that a couple of the jets needed cleaning but that everything else looked pretty good. I also pulled the valve cover to check clearances and found that one of the intake valves and both exhaust valves were slightly out of spec so I reshimmed. All valves are now at the tight end of the spec range but are in spec. I just finished putting it all back together with high hopes of being able to kick it over but I was disappointed. I pulled the plug and checked for spark and it definately has spark.

Is there something else I need to check? Will it just take some time since it's been sitting for so long? Should I buy a carb rebuild kit and go through the whole thing? Any advice would be a huge help. I'm about to just bring it to the dealer and pay them to get it going.


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  • grayracer513

Posted November 26, 2011 - 05:23 PM


Double check:

  • Flywheel location: Pull the plug and probe for TDC with a long Phillips head or? Once you find it, see if the flywheel agrees. If it doesn't, the key is sheared or out of place.
  • Cam timing.

Put a new plug in it, too.

When cold starting, start by giving it 3-4 good twists on the throttle, then push it through once, then kick with no throttle (choke on). If it fails to do anything, try it with the throttle VERY SLIGHTLY opened (you might also just turn the idle speed up a half turn).

If it tries to light but won't catch and run, it's most likely still a carb problem. Sitting in long term storage messes with the pilot circuit pretty hard. Fuel dries, leaving a thick layer of hard varnish that won't dissolve easily in carb cleaner and won't blow away. Read:


  • Norcalyz

Posted November 26, 2011 - 05:47 PM


Awesome thank you! I will check those things tomorrow!

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