Checking the valves on a yfz

[Norris3710]

I am wanting to check the valve clearences on my yfz and just wondered if i could get some direction. thanks

[hontrx265r]

I guess I'll take a stab at it. I've done it many times, I do however assume you have some knowledge of how the engine works, and where everything is, a service manual is also only 30.00 bucks and will guide you in all your mechanical needs. MOTOR SHOULD BE COLD!
1. Remove plastic, and gas tank anything thats in the way of the valve cover.
2. Remove the cover so the cams and caps are exposed.
3. You will now need to remove both plugs in the stator cover, you'll need a 14mm socket wrench, with extension and a small flash light. with the socket wrench your going to roll the motor to top dead center TDC very slowly. You will be looking for the I on the flywheel to line up with the notch from where the small plug is missing.
SIDE NOTE: when at TDC the cams lobes will be facing away from each other and upward like a Y but very close to layed out flat. dots on cams level with top of head.
4. At this point you will need a feeler gage. I have hotcams and my exhaust is .015 intake should be .010, but check with your dealer.
5. Just slide the gage between the cams and the valve caps. It should feel snug, but you should not have to force it between the cams and caps.
6. If the adjustment is out, you will next measure what the distance is with the gage. record it for each indivdual valve because they will probably vary. write it down (and make a diagram for intake and exhaust)
8. zip tie the cam chain to the cams so they do not skip teeth.
9. loosen the bolt to the cam chain tensioner, take a small flat head screw driver and insert it inside and screw the flat head screw clockwise till it bottoms, your cam chain should have loosened up.
10. Unbolt the cams, remove the covers, there are C clip under them so becareful not to drop them inside the engine. cover the chain slot with a rag.
11. Lift the cams out and, carefully pull each cap on the valves to reveal the pucks. (the pucks will probably stick inside the caps from oil) keep these pucks in order so you now which valve they came from, its very important to not mix them up.
12. Next take your measurements for each valve and the puck that matches the valve, and bring it to your local dealer. They can look up a reference chart that tells you which puck to replace each one with, to compansate for the (too lose or too tight clearance)
13. Keep these in order also, bring them back to your bike and put them in each proper valve.
14. Replace the caps, cams, and cam covers(use a torque wrench and look up the torque spec.
15. After you have assembled that, double check your engine is at top dead center because surely it moved a little.
16. Recheck your work with your feeler gage. (everything should be A OK)
17. Turn the flat head inside the cam tensioner counter clockwise it should un-wind itself but make sure its tight again. plug it.
18. Plug the holes in your stator cover, replace your valve cover, tank and plastic.
Start your bike, listen for smooth bliss............SOUNDS GREAT now go rip ***!!

[crayfz]

Thats some thorough info.

[yfz450inMI]

Here's a step by step with pictures

http://www.yfzcentral.com/invision/index.php?showtopic=35079 (Checking valves)

[harescrambles]

Originally posted by yfz450inMI
Here's a step by step with pictures

http://www.yfzcentral.com/invision/index.php?showtopic=35079 (Checking valves)


The link no workie.
how about this one http://www.yfzcentral.com/invision/index.php?showtopic=35079

[Norris3710]

Thank you so much