04 Yz450f Valves

So yesterday i checked my vavles clearences. Both the Intake and Exhaust valves were out of spec. Two of the Intake were .08mm and one was .10mm. The Exhaust i could forcefully fit .32mm but a .25mm felt like it was pretty snug :moon:

Any advice would be great im probably going to pick up a shim kit today and some new tools. :p:ride:

anyone have an opinion? should i keep them how they are or should i adjust them?

First, the spec on the exhuast is .20-.25mm. I don't know what you're doing with the .32.

Second, since the book calls for .10-.15 on the intakes, and two of them are at .08, then obviously they need adjustment.

Shim kits are a waste of money unless you are in the business of working on these things. If you have two valves out, you'll probably be able to use the shim from one in the other, and get the second one from a dealer for $6. If your Yamaha dealer doesn't have them, check the Honda store. They most likely will. Shims for CRF450's and most other big Japanese MX 4T's are the same 9.48mm diameter.

Thanks gray. I just wanted a second opinion sence this will be the first time im acculy going to work on the bike, other then maintenance. So i should pick up 3 170 for intake and 2 185 for exhaust?

So i should pick up 3 170 for intake and 2 185 for exhaust?

Why? You only have two intake valves out of spec. The one at .10 is fine.

What shims are in the two intakes that are at .08?

What is the actual clearance of the two exhausts?

I just checked them again. The exhaust is fine. .20mm slid in .25mm was hard to get in. note-but i could fit a .45mm in but it sounded like it acculy moved the spring and valve, not sure if it matters.

All intake took a .08 but i couldnt get the .10mm in

havnt checked the shim sizes yet just checked the clearence.

I just checked them again. The exhaust is fine. .20mm slid in .25mm was hard to get in. note-but i could fit a .45mm in but it sounded like it acculy moved the spring and valve, not sure if it matters.

All intake took a .08 but i couldnt get the .10mm in

havnt checked the shim sizes yet just checked the clearence.

If you haven't checked the shims, you have no way of knowing what's in there. It will be a mix of several sizes, and as I say, you will probably be able to move one or more of them to a different location. for instance if one has a 188, and the one next to it has a 185, moving the 185 to replace the 188 will open up .03mm more clearance, and you will have .11, instead of .08. Then you'd only need to buy two.

alright i took the cams off and checked the shim sizes. 186 188 186. going to the yamaha dealership to pick up 2 new shims

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