Just switched to yz timing and..........

Hey John,

I'm ready to do this mod now, most everything else on the bike is about perfect. How long would you say it takes?

Not sure who John is, but here's some input if you want it. Now that I've been into the engine, I could probably do the mod in around 30 minutes. The most time consuming part is taking your time moving the exhaust cam. You need to be very careful when doing this as to not let the cam chain slip off of the crank. It is also a pain to try and keep the engine at TDC. Some have suggested keeping the bike in 5th gear. I didn't try it, but seems like it would help. Just make sure your timing marks on the intake cam stay where they're supposed to be, then set the exhaust cam off of that.

If you've adjusted your own valves before, you could easily do this mod in a half hour. If not, maybe an hour.

My tips. Don't remove the plug on the case in order to turn the engine over with a wrench. Just have someone use the kick starter while you watch for the "I" mark in the hole. If you take the lower plug out, you will lose some oil. Not all of it, but a significant amount. Also, I don't see why you would have to remove the cam chain tensioner. Just use a small screw driver (turn clockwise) to lock it. Also, be carefull removing the valve cover. You will want to re-use this gasket. Hope this helps.

jchantzWR400F, I'm John and Stefe9999 and I have ridden together and he lives fairly close to me.

I think if you have't ever checked the valves, it will take you 1-1.5 hours to change the timing. If you have, you already know how to get the valve cover off. Once that's done, it's a piece of cake to change the timing.

I also agree about not taking the cam chain tensioner out. I still can't figure out why this is needed? Just back it off and there is plenty of slack to lift the cam and rotate it.

I also agree about not taking the cam chain tensioner out. I still can't figure out why this is needed? Just back it off and there is plenty of slack to lift the cam and rotate it.

John you have a few extra hands that we dont know about. Once you unwind the tensioner, you remove the screwdriver and it snaps right back tight. So how do you hold the tensioner open with the screwdriver and remove the cams all at the same time??? Neat trick.

I did my cam swap twice on the 450 and John needs only 2 hands and he is right the tensioner will stay in the retracted position until you turn the screw slightly which must cam the spring back into action. So you dont have to keep a tool on it. :thumbsup:Job takes 1 - 1.5 hours taking your time. Safety wire the chain to the frame tube and watch out for that half round retaining clip that wants to drop into the engine. :)

I second that the cam chain tensioner will stay in the locked position until you turn the screw driver counter clockwise to unlock it.

Blah Blah Blah Blah. Bottom line is, you're POS blue ball still won't outrun me. :)

Dont forget to say you can outclimb Chantz as well Jason! :):D :D

Dont forget to say you can outclimb Chantz as well Jason! :):D :D

That's one of the things I like about Jason, he's got a great sense of humor. :D

Blah Blah Blah Blah. Bottom line is, you're POS blue ball still won't outrun me. :)

Hold on a second, I've got to work up to this one....

:D :D :D:D:D:D:usa::usa::usa::usa::usa::lol::jawdrop::jawdrop::jawdrop::jawdrop:

No really ..... :jawdrop::jawdrop::jawdrop::jawdrop::jawdrop::jawdrop::jawdrop::jawdrop::jawdrop::jawdrop:

Hey Chantz,

Glad you got your bike up. Have you de-octopussed your carb?

Inquiring minds want to know... :)

Nope...haven't done the De-Octopuss Mod yet. I was looking at it the other night thinking it didn't look so bad. I also haven't done the BK Mod/Wheel Collar Mod/Accelerator Pump/whatever it's called mod. That one I'm not sure of....

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