Damn stumped on this yz450

Yamaha YZ450F

30 replies to this topic
  • jackiefresh69

Posted October 27, 2015 - 07:12 PM

#21

How tight were they?

Spec is exhaust .20-.25 intake .10-.15
I had thisImageUploadedByThumper Talk1446001884.391298.jpg

  • moto867

Posted October 27, 2015 - 07:14 PM

#22

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

  • jackiefresh69

Posted October 27, 2015 - 09:01 PM

#23

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.

  • moto867

Posted October 28, 2015 - 02:59 AM

#24

Oh

  • moto867

Posted October 28, 2015 - 03:08 AM

#25

Was it doing this before you shimmed the valves?

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  • grayracer513

Posted October 28, 2015 - 06:26 AM

#26

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? 



  • jackiefresh69

Posted October 28, 2015 - 12:33 PM

#27

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

  • jackiefresh69

Posted October 28, 2015 - 12:50 PM

#28

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

  • jackiefresh69

Posted October 28, 2015 - 08:40 PM

#29

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

  • jackiefresh69

Posted October 29, 2015 - 10:49 PM

#30

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

  • pomoco

Posted October 30, 2015 - 02:32 AM

#31

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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