Did I do the YZ cam conversion correctly?

11 replies to this topic
  • kincade

Posted May 06, 2005 - 08:19 PM


Just put the 2004 YZ450f cam in my 2004 WR 450 tonight; Clearances came out all right; but on the new exhaust cam, the 'punch marks' are placed differently than the old WR cam. The question is, do I use the lower punch mark and line up up with the top of the case, or do I make sure the upper punch mark is in the same place on the chain as the last was.

If I place the upper punch mark on the same place in the chain the old one was located, the lower mark is not placed correctly on the case.

Here are some photos of what it looks like installed.

Posted Image

Posted Image

Can anyone advise me on this?

  • MX_Ryda_192

Posted May 06, 2005 - 08:25 PM


i think the mark is supposed to be aligned with the case....im sayin just try it at the mark with the case and check the measurements again, if there off, then i guess it goes how ya have it :) cant hurt anything by tryin it

  • kincade

Posted May 07, 2005 - 08:05 AM


Both lower marks ARE aligned with the case... I don't understand what you're saying?

  • kincade

Posted May 07, 2005 - 08:58 AM


Crap; now I'm really confused. I've read there should be 12, 13, and 14 marks between the upper (12 oclock) marks. Can anyone clarify what the cam timing should be when putting a YZ cam in a WR? I don't wanna start this thing up and bend my valves!

Thanks for any help you can give!

  • WheelsUp

Posted May 07, 2005 - 10:26 AM


The YZ cam marks are different than the WR marks... they are rotated by "one" tooth.
When installing the YZ cam, there should be the same number of pins between the top marks, and the marks on the case should line up the same way as stock.

As far as the number of pins between the marks, the 250 has 13. I'm not sure about the 450. When re-timing an '01 or '02 to YZ timing, you move it from 13 to 12, but that is when you are not changing the cam itself.

  • kincade

Posted May 07, 2005 - 11:24 AM



Thanks for the advice; I guess what I'm saying is that I have to choose; they marks on the case can either line up, or the upper marks on the pins can line up. Not both.

Did my photos look like it was correct? Or Incorrect?

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  • kincade

Posted May 07, 2005 - 12:32 PM


Just took some photos of the other side for reference:



Little confused still ; this post says 14 dots:


And this one 13:


Anyone know what the stock count between pins are on the YZ450?

  • kincade

Posted May 07, 2005 - 12:33 PM


Arrrgh, and this one says 12 pins!


  • clark4131

Posted May 07, 2005 - 12:36 PM


Make sure they're not talking about different things. Changing the WR cam to "YZ timing" is not the same thing as putting in a YZ exhaust cam...SC

  • kincade

Posted May 07, 2005 - 03:31 PM


Well, I'm even more confused now, if that's possible.

I just looked at a manual from a 2004 YZ450f; in the diagrams in valvetrain and cams it shows 14 pins between the two marks. Unless they just use generic diagrams for all the manuals, then that would put my exhaust cam lower pin below the case...


  • flatnacker

Posted October 23, 2005 - 02:42 PM



  • ISBB

Posted October 23, 2005 - 02:48 PM


from the looks of it the exhaust cam is off... but dont take my word for it... i remember readign somewhere as long as the lobes were opposite each other or straight out... instead of how you have it - / they need to be - - if that makes sense...


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