Timing a wr426 from wr timing to yz timing inc picture, to help others.

I have done a engine rebuild to my wr 426 and have noticed there are several forums asking how to time a wr to yz timing... I have put a couple pictures up to help the few that need it... hope this helps you fellow riders good luck. :excuseme:

IMG_0372.jpgIMG_0376.jpgIMG_0378.jpg

Edited by djrevz

I received a private message asking What the wr timing is... If you look back at the cams the exhaust cam (left cam) this cam wants to turn anti clockwise 1 tooth so the 'E' punch mark is level with the head instead of the 'I' punch mark. (IMPORTANT DO NOT LOOSEN THE CAMS UNTILL YOU HAVE SLAKEN OFF THE CHAIN TENTIONER)

Wr timing is 13 pins between cam marks and yz timing is 12 pins between cam marks. make sure your flywheels 'l' in the 'Hl' lines up with the timing marks as shown in my first thread above. to check if the cams sit correct either make sure the chain tensioner is removed so you can put your finger in the hole to put tension on the chain slide arm or if you chose to keep the chain tensioner on.... make sure the cams are held down and loosen the tensioner so its taught to see were the cams sit.

Edited by djrevz

Chain tensioner? Yes I know probably sounds like a dumb question. But first rebuild on a bike like this.my son 16 thought he was doing me a solid. Changing out my spark plug and broke it off at the threads. So I'm getting ready to pull the head to see what can be done to salvage it. But while I'm at it would like to do any mods while I'm at it. So any help would be greatly appreciated. All I know is I have it at TDC. Valve cover is off and that's when I realized. I need help.

Edited by Christian Jennings
On 03/08/2017 at 1:27 PM, Christian Jennings said:

Chain tensioner? Yes I know probably sounds like a dumb question. But first rebuild on a bike like this.my son 16 thought he was doing me a solid. Changing out my spark plug and broke it off at the threads. So I'm getting ready to pull the head to see what can be done to salvage it. But while I'm at it would like to do any mods while I'm at it. So any help would be greatly appreciated. All I know is I have it at TDC. Valve cover is off and that's when I realized. I need help.

If the insulator and centre electrode came out with the top half of the plug, and there's just the steel threads stuck in the head, try jamming a large flathead screwdriver into the hole and undoing it. It works if the threads aren't damaged

Ok I got my chain tentioner removed cams in place but still feels like chain is to tight to adjust cams to set timing. Wr to yz is there something I'm missing?

And does anyone know torque specs for cams?

7 hours ago, Christian Jennings said:

Ok I got my chain tentioner removed cams in place but still feels like chain is to tight to adjust cams to set timing. Wr to yz is there something I'm missing?

You need to download a factory service manual from Yamaha's web site.

You DO NOT remove the cam chain tensioner......

I had the head off that's why I took off tentioner. Had to do some other repairs. Ie take broken spark plug out and replaced all gaskets and o rings. So now I have head on cams in timing set to yz. And have downloaded oem repair manual. So have all my specs. Appreciate the help.  One more question, why not take off chain tentioner?

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