wr450 2007 cams in yz426


4 replies to this topic
  • dg400sm

Posted February 21, 2016 - 01:29 AM

#1

i understand that this topic has been covered quite a bit but maybe not with this combo. my yz426 is standard in everyway. there is a set of wr450 2007 cams on ebay going cheap, both exhaust and inlet. could these cams be bolted straight into my yz426. that way i would have the auto decompression feature and a much smoother power delivery. i've never liked the power delivery on my yz so would be more than happy to shed some HP in favour of more usable power delivery



  • grayracer513

Posted February 21, 2016 - 07:12 AM

#2

You can't use the intake cam because you will have no way to time ii.  The intake cam was the same on both the WR and YZ426 models anyway.  You should be able to get the WR exhaust to work, however.   Instructions below are for the YZ450 cam.  You may need to adjust things a bit to get it to work. 

 

http://www.thumperta...49#entry2979654

 

http://www.thumperta...53#entry4458141



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  • dg400sm

Posted February 21, 2016 - 07:57 AM

#3

thankyou for the links. i'll study them as best i can. i am sort of new to this forum so still have a lot to learn. still not fully understanding of why i can't time the wr450 inlet. if it has timing marks on the cam can't i put my own timing marks on the yz426 cylinder head as in copy the wr450 cylinder timing marks or does this not work too due to the longer stroke, if that doesn't work could a degree wheel be used



  • grayracer513

Posted February 21, 2016 - 01:34 PM

#4

Different head, different valve angles in the head, different height of the cam cover deck, longer stroke, all sorts of reasons.  The cams simply weren't made for the head in the first place.  

 

I can't think of a single reason to even try to use the WR450 inlet cam anyway.  It's very little different from yours.  The exhaust cam is the big difference between YZ and WR cam timing.



  • dg400sm

Posted February 21, 2016 - 06:15 PM

#5

Different head, different valve angles in the head, different height of the cam cover deck, longer stroke, all sorts of reasons.  The cams simply weren't made for the head in the first place.  

 

I can't think of a single reason to even try to use the WR450 inlet cam anyway.  It's very little different from yours.  The exhaust cam is the big difference between YZ and WR cam timing.

ok that makes a lot of sense thankyou. i wanted to use the wr450 inlet as i was under the impression the 2007 model is quite a bit milder than my yz inlet cam but its starting to seem much simpler to spend the little bit extra on the hotcams exhaust cam. thanks again :)







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