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MountainMax

Just wanted to say Thanks (adjusted my valves today)

14 posts in this topic

Tonight I adjusted my valves for the first time ever, Thanks to you guys here in this forum it was a breeze, I found three valves out of spec and I was prepared by your tip on buying a hotcam shim kit, I found the proper shims using the yamaha chart and bam, I'm all back in spec again, they were tight, i guess this is the norm right? Anyhow Thanks again guys for a great wealth of knowledge here.........especially for a thumper newbie......

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Tight from your YZ cam? Tight but still in spec?

How does she start now with the magic button?

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Well, thanks for the reminder. I have right around 550 miles on my WR450F and need to get this shim kit also to do my valve adjust. Still runs and starts fine, but I know the valves will be on the tight end of the spectrum.

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Yeah, there was one exhaust valve that was tight after the yz cam, and two intake valves, She's still a bit cranky starting with the magic button, I just tried some jets late last night, will find out today if it's any better....... first kick every time with the manual starter though..... :excuseme:

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Still runs and starts fine, but I know the valves will be on the tight end of the spectrum.

Then why adjust? Better to be tight end than loose.

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three of my valves were too tight, they were out of spec actually, the others were right in between, now they are all in between, should be good for a while now.

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No to the valve guard - I was told to avoid it but dont have any basis for that.

Right - valve clearances will be tight after break in but if in spec just leave them or shim on the tighter side, as stated earlier.

Looks like I'd better get one of those shim kits - what shims do you get??

I also heard/read the CRF shims are the same size but offered in smaller thicknesses so easier to get close to the exact spec you want. :excuseme:

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I bought the HOT CAMS shim kit so I will heave whatever I need, when I need it, and could be cheaper in the long run as they are expensive from Yamaha , and yes the kit I have fits other models also with the same size shims.

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The BIG bonus w/ the SHIM KIT, is you have them in your tool box.

When shimming my WR, the parts guys was supposed to order it.

I asked if the SERVICE Dept would be willing to help.

The response, "I doubt it, but they're dowstairs."

Went to the Service Guy and he said, "SURE, I will swap what you need with what you have."

It worked that time, but for the future a kit would almost be invaluable.

A REFILL KIT is available also. It keeps you from buying the fancy-shmancy box it comes in, albeit it IS organized...

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Be carefull assuming tight valves are better than loose valves. It's actually better the other way around. Usually the problem, especially if you don't use a valve seat lubricant, is they pound up into the seats, closing the valve clearance up. If it's an inlet valve you will get backfiring through the carby. If it's an exhaust valve, it can lead to leakage past the valve, which overheats it because it can't transfer its heat to the seat and head so the edges of the valve burn away until you hear it backfiring in the exhaust or, more commonly on high revving motors, the head of the valve drops off - carnage and mayham. Loose valves are just noisy, or worst case you chew up your cam or valve stem.

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now you got me scared, lol. I will just check mine more often and try to keep them in the middle of the spec range........ I found my regular feeler guages are a bit wide to get in there proper, does someone make a smaller narrower set for these kind of things? What are you guys using?

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now you got me scared, lol.

No worries mate, you just need to look for a change or a trend. checking them more often until you get confident they are not changing is a good idea. If you just changed the cams, might be an idea to run the bike for 20 hours or so and check them again after everything settles in. I do mine every 500Kms, it's no hassle really, takes about 15 minutes. (One beer job). I use normal feeler gauges which only just fit too.

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Right on, (whew) thanks for the info. I will recheck mine after riding this weekend to see how they are doing.

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