Adjusting valves for the first time - need help

[legaleli]

I need some clarification - I went on to Bikecliff's website and read the valve adjustment references, but I am not clear on what I should be measuring.

Below is a picture of my #4 exhaust with the lobe facing forward. The shim is still in place. You can see my feeler gauge in the picture where I believe I should try to measure.

My question... what gap should be measured here? As my bike is now there is a direct connection between my shim and the cam... there is no space between the two that I can measure.

[tkent02]

Then that shim is too thick, there should be .03mm to .08mm between them.

Good thing you are checking it, when the clearances go to zero, valve damage happens.

How thick is that feeler gauge that won't fit?

See if you can spin the shim in the bucket with your finger, if you can there is still some clearance, if you can't there is none, bad news.

[legaleli]

HELP! Experienced GS knowledge required!

I need some real help here (again) . I am certain of the measurements and I don't know what my next step should be. My thinnest feeler gauge is .038 mm.

By the way... doing this work today was a lot of fun.

Here are the measurements:

#1 Cylinder
Exhaust = 0 mm clearance / shim 2.65 mm
Intake = .038 mm / shim 2.55 mm

#2 Cylinder
Exhaust = .038 mm VERY TIGHT clearance / shim 2.65 mm
Intake = .038 mm TIGHT / shim 2.50 mm

#3 Cylinder
Exhaust = 0 mm clearance / shim 2.55 mm
Intake = .076 mm / shim DID NOT INVESTIGATE

#4 Cylinder
Exhaust = 0 mm clearance / shim 2.60 mm
Intake = 0 mm clearance / shim 2.45

[azr]

The instructions from Cliffs site are pretty easy to follow so you're probably doing it right. It looks on your photo that you are measuring in the correct place. Just make sure the lobe is in the correct placement and put your feller guage inbetween the shim and lobe. Make sure you are using the correct feller guage. How was the bike running before you started this confusing project? the shims you've looked at already look pretty normal for a typical shim job. Why don't you replace your thinnest shim, 2.45 into one of the tight valves and see if it makes the proper difference. If it does then you'll know you are doing things right. You can even do that to the unmeasurable valves to get proper measurement but it's alot more work.

[Steve]

One of your next steps could include the suggestion at the end of my sig.

.

[Nessism]

For those valves without clearance the next step is to install a shim one or two sizes smaller than what's in there now and recheck. It helps to have a stock of appropriate sizes.

[legaleli]

For those valves without clearance the next step is to install a shim one or two sizes smaller than what's in there now and recheck. It helps to have a stock of appropriate sizes.

Hi Nessism, AZR and Steve:

Firstly thanks for your replies!

I have sent the request as per Steve's signature. And AZR... swapping shims is a great idea.

Nessism, I was wondering exactly what you suggested... I was wondering if I could just order shims a couple of sizes down from the shims in place now and replace the current ones... or would I have had to do something first...

It looks as if my next step really is just to make an order to Z1!

I AM WONDERING... "one or two sizes smaller"... if my current shim size is 1.65mm then would a 1.55mm shim be TWO sizes smaller?

[azr]

The shims are cheap, start at 130 and go up ordering 2 of each. It looks like you already have a bunch of the thicker ones. Throw that thin 145 in and see what reading you get. Maybe you want to go a bit lower than 130 if they are already that tight. See what you get after you swap for the 145. Let us know what you get. I'm still curious how the bike was running before you started this project, especially if the shims were that tight!

[Nessism]

The valve train is very stable on these GS bikes. The problem come in when people don't adjust the valves and then they start to burn. For your bike I'd order a handful of 2.55's and some 2.60's. No need to go lower than maybe a couple of 2.50's to have on hand.

[azr]

I've done mine and had to go as low as 2.40, is that indicative of something looming
?

The valve train is very stable on these GS bikes. The problem come in when people don't adjust the valves and then they start to burn. For your bike I'd order a handful of 2.55's and some 2.60's. No need to go lower than maybe a couple of 2.50's to have on hand.

[Nessism]

I've done mine and had to go as low as 2.40, is that indicative of something looming
?

I'd say yes, unless the valves have been cut before. Most bikes leave the factory with shims in the 2.75 range, although some are lower and I suppose some higher. There would have to be a bit of wear to be in the 2.40 range.

[legaleli]

I'd say yes, unless the valves have been cut before. Most bikes leave the factory with shims in the 2.75 range, although some are lower and I suppose some higher. There would have to be a bit of wear to be in the 2.40 range.

Got a bunch of shims ordered. The smallest I ordered was a 2.3, and a 2.35, and the rest up to 2.5.

I ordered the 2.3 and 2.35 because the #4 intake is currently at 2.45 and has NO clearance. I'm hoping 2.35 will be fine as the replacement shim.

AND BY THE WAY... I ordered the shims a few hours ago online at Z1 and noticed about 1/2 hour ago that it didn't yet update on their website. I called to ask if they received the order... and yes... they received it... processed it... boxed it... and it's going out in today's mail! Fantastic speed in their service.

On another note... I wonder how long I have until I need to swap out the valves...

Thanks to everyone for the help so far!

[bellucci]

I know that you would not do this, but make sure you have a shim in every bucket when you rotate the engine... sounds silly, but I just want to remind you...
Curt

[legaleli]

I know that you would not do this, but make sure you have a shim in every bucket when you rotate the engine... sounds silly, but I just want to remind you...
Curt

It's NOT silly... and I almost learned the hard way what happens... I did rotate the lobe onto the bucket without a shim in place and then spent 30 minutes trying to keep the valve compressed so I could move the lobe back out of the bucket without ruining the cam!

Thank goodness I looked at it REALLY carefully before trying to rotate it, and thank goodness for the "double zip tie method and 1/2mm feeler gauge" method devised me ME to keep the valve compressed!

[legaleli]

Compresion

OH OH... Keep in mind that I'm doing a valve job and carb job because I think #4 cylinder is not doing its job... it felt unbalanced (but there is ignition in the cylinder).

So I'm rotating the engine with a wrench and examining the cam chain (can't hurt)... the carbs are off because I'm cleaning them. For giggles I do "finger compression" check on #4 sticking my finger int he sparkplug hole and I rotate the engine slowly. I CAN HEAR ON COMPRESSION THE AIR LEAKING FROM THE INTAKE VALVE.

When I checked my valve clearances there was no clearance on #4... intake and exhaust. I have the shims on order.

Someone please tell me:

Compression issues can arise from the valve clearances closing AND a shorter shim might fix this...

or that rebuilding the top end is fun for a beginner!