Valve clearances.

I just checked my valve clearances on my 80 650 maxim. It has 49,568 on the clock. I have no idea when the last valve adjustment was. I use the zip tie trick to get the shims out. Here is what I have.

cyl. #1

INTAKE shim: 2.80mm EXHAUST: shim: 2.75mm

clearance: less than .05mm clearance: .08mm

cyl. #2

INTAKE shim: 2.70mm EXHAUST: shim: 2.70mm

clearance: .08mm clearance: .10mm

cyl. #3

INTAKE shim: 2.75mm EXHAUST: shim: 2.70mm

clearance: .08mm clearance: .13mm

cyl. #4

INTAKE shim: 2.80mm EXHAUST: shim: 2.80mm

clearance: .05mm clearance: .08mm

The smallest feeler gauge I had went to .05mm. Intake #1 is so tight that I could not even get .05mm to fit. I could tell the valves are in need of adjustment by the sound of the exhaust. From the charts I'm looking at the shims I need:

cyl. #1

INT 2.70mm EX 2.65mm

cyl. #2

INT 2.65mm EX 2.60mm

cyl. #3

INT 2.70mm EX 2.65mm

cyl. #4

INT 2.70mm EX 2.70mm

If someone would double check me for any mistakes. Is it possible to reuse some of the old shims on the ones that need that size and just order the ones I don't have?

 

from what I have heard reusing shims should only be a temporary thing. the aftermarket shims chacal sells are only $7 vs $17 oem.

can't verify your numbers as I'm on my cell in the car lol

 

Lol. I'm always on YIM on my blackberry everywhere I go. I just want to make sure that I order the right shims.

 

Numbers look good to me.

 

Looks like you used the chart, and they all look good to me.

Old shims are only good for testing; I would NOT recommend using them, especially with as many miles as your motor has. Using worn shims can result in cam lobe wear, not a good thing. Plus a spit shim can destroy your top end.

Remember no magnets! when pulling the shims.

 

Fitz,
Why no magnets? Just curious.

 

Very tiny iron particles are constantly being made by the chains and transmission gears. If the shims get magnetized, these particles would collect there, probably standing on end too!! Then the cam lobe comes down with 200 LBS of force, fifty times a second.
Now a couple powerful, tiny magnets in the oil filter housing would be a great idea. I've been sticking magnets to the outside of car oil filters for years.

 

haha I think fitz meant SPLIT shim not SPIT hehe.

magnets in the oil housing, now theres an idea I like!

 

No, I meant SPIT as in spit out from between the top of the bucket and the cam, at speed...

 

Wouldn't that SPIT cause the cam lobe to SPLIT it?

hehe

 

Doubtful. They're hardened. The aluminum head casting is not...

 

Thanks fitz. Yes I did use the chart and I read about not using magnets before I ever pulled the valve cover. Some of the shims I could not read the numbers on so I used my digital calipers. I bought it right before I stopped working as a machinist and have not had the opportunity use them much since. It is almost time to have them recalibrate again. Hopefully this will fix my idle after it warms up. It runs and idles great when cold but once it warms up the idle varies as much as maybe 300 rpm. And there is a difference in tone between the mufflers. One sounds just right while the other has a bit of a popping sound to it. I have been wanting to get these valves adjusted so I can finish my tuning of the mixture screws and syncing the carbs.

 

+1 Rob. With valves as tight as a couple of those are you won't have much luck carb tuning. You will be flabbergasted at the difference it makes. You THOUGHT your bike was powerful before; wait until you get the valves done and the carbs sync'ed. With that many miles, it was in sorry need. Glad to help.

Keep the flame---Fitz