04 yz450 valve adjustment with hotcams

3 replies to this topic
  • dwnlowx

Posted February 16, 2007 - 04:25 PM


im putting in a set of hotcams and i see a couple different valve adjustment settings,hotcams info says that exhaust valve is to be set at .20mm and intake at .15mm is this correct

also is there any jetting changes i might need to make

is there any break in tips from experience


  • grayracer513

Posted February 16, 2007 - 04:35 PM


Intakes .10-15mm

Exhausts .20-25mm

Cam grinders generally want the engine to be run at more than 2000 rpm for the first 15 minutes of operation to make sure that the cam lubes well during that time.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • dwnlowx

Posted February 16, 2007 - 08:20 PM


thanks gray

is tighter better our if there around there dont touch em
im just curious and i need to do it right

  • grayracer513

Posted February 16, 2007 - 08:51 PM


In looking at any such clearance specification, either of the two numbers given, or any number in between them, is within the specified tolerance range, and therefore good. It's well to bear in mind that the entire range of the spec is slightly less than .002" wide, so choosing between the tight and loose edges of the spec is quite literally splitting hairs.

"If they're around there," isn't acceptable. Any measurement within the specified range is. If you could set them to a particular exact clearance, you would choose the tighter of the settings.

Also, While Yamaha OEM and Hot Cams shims are only available in increments of .05mm, Honda sells them in increments of .025mm, so you can be more precise if you've a mind to. Be sure to get the 9.48mm diameter shims, such as those used in a CRF450, if buying from Honda.

Related Content


James Stewart back on a YZ450F by YamaLink

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  47 replies

Should I buy this bike? help....... by Numsa Hul

Dirt Bike   General Dirt Bike Forums   What bike should I buy?
  • * * * * *
  • 10 replies

Is it worth it? (Cam and High compression piston) by macgi77

Dirt Bike   Make / Model Specific   Honda   CRF 150/230 F/L
  • Hot  36 replies

Yamaha YZ450F 2017 by Chris.GVS

Yamaha YZ450F 2017
  • * * * * *
  • 1 review
  • Last review by Tommyk_55
  • On January 15, 2017

The "going back to the other darkside" adventure... by Monk

Dirt Bike   Make / Model Specific   KTM   250/350/450/505 SX-F & XC-F (4-Strokes)
  • Hot  113 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.