cam question

[Murmy26x]

Have a feeling this is one for Grayracer,

But is there a difference between the cams on 06-07 YZ 450 and 06-07 WR 450?

And also the same question from the 06/07 YZ 450 and the 06/07 YFZ 4 wheeler motor?

Looking to make one of my dirttrack motors more mellow down low. Already looking to have weight (lb and a half) added to the crank also and it's already low compression. There are a few guys bouncing cams back and forth on their honda's between the X model and the R model to tone them down some bit. Wondering if i can do the same with my Yam's.

- Steve Murray

[grayracer513]

There's several different cam combinations in the 6 engines you mention.

• '06 YZ450 (intake, then exhaust)
  
• 5TA-12170-10-00
  
• 5TA-12180-10-00
  
• '06 WR 450
  
• 5TA-12170-10-00
  
• 5TJ-12180-20-00
  
• '07 YZ450
  
• 5TA-12170-20-00
  
• 5TA-12180-20-00
  
• '07 WR450
  
• 5TJ-12170-00-00
  
• 5TJ-12180-30-00
  
• '06/'07 quad
  
• 5TA-12170-10-00
  
• 5TG-12180-20-00
  

The '07 YZF cams as a set would push the power range up a little, which would soften the low end a little at no real expense to the overall peak. Otherwise, I'd think that the exhaust from the '06 WR would be the next choice.

I have no precise grind info on any of these apart from the lift figures in the manuals.

[Murmy26x]

Thanks Gray!