Damn stumped on this yz450

How tight were they?

Spec is exhaust .20-.25 intake .10-.15

I had thisImageUploadedByThumper Talk1446001884.391298.jpg

I mean before you adjusted them. Were they very tight or just a little? Just wondering about the condition of the valves

I mean before you adjusted them. Were they very tight or just a little? Just wondering about the condition of the valves

Yeah that was the clearance before I adjusted them . There all in the middle now.

Oh

Was it doing this before you shimmed the valves?

Yeah that was the clearance before I adjusted them . There all in the middle now.

 

Keep an eye on that "intake 1".  Check it again in one or two rides to see if it increases again.  

 

Did you find a reason for it being looser than spec? 

Anyone got anything else to try ? I suppose I should pull the head off ???

Keep an eye on that "intake 1". Check it again in one or two rides to see if it increases again.

Did you find a reason for it being looser than spec?

Okay will do . No I havnt yet but I'll check again and see if it's loosened up again

Okay will do . No I havnt yet but I'll check again and see if it's loosened up again

yep intake 1 is all good

So I'm not sure if any one cares or not but it might help someone . I pulled my head off and filled it up with petrol and it all leaks through very quickly past the valves so I'm guessing I'm up for a valve job

That's what a leakdown test does without taking the motor apart. Many people forget that valve clearance can be OK, but the valves may not be making a good seal. At least you've got it figured out. Get the head done right. Don't just throw some valves in or.

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