04 CRF450 Starting mystery

[darrenposton]

I've always used the same starting procedure to start my 04 CRF450 no matter what the weather conditions and its always started first or second kick.....1) pull choke 2) Twist throttle twice 3) kick. All starts after initial start of the day required no choke or throttle...usually starts first or second kick.
This last weekend I followed my usual routine but it didn't start even after 5 kicks....twisted the throttle once more, fired right up. All the other starting attemps that day required at least one twist of the throttle to get it started. Had no problems running after starting....ran as strong and hard as always. I did experience one off idle hiccup when exiting a really tight off camber when I let the revs get too low and snapped the throttle wide open...but that was it nothing else or I should say everything else was good.

Any ideas what might have suddenly caused this?

 

[Rich Rohrich]

When was the last time you checked the intake valve clearance?

 

[darrenposton]

the weekend before last.....one was .010 in. the other was .011 in.

 

[Rich Rohrich]

the weekend before last.....one was .010 in. the other was .011 in.

Your valve clearance is set at 0.010 inch on the intakes? You sure about that?

 

[darrenposton]

Why? What should it be?

 

[Rich Rohrich]

Spec is .006" (+ or -.001" )

 

[mike black]

hey their
i got 6 h on a 2005 crf 450 and she is runing good but the first start of the day is aways hard. you guyws know why?

 

[fnengineer]

Check the intake valves like Rich said...when the intake tightens up it is a beast to start, and a valve job is in the near future.