Shims for valve ajustment

[jon]

I have an 1983 gs850L .Can anyone tell me what shims are the most likely shims I may need when checking and adjusting the valve clearance. I would like to have an assortment on hand before taking it apart. Also where can I purchase these. Aside from z1. Thanks.

 

[salty_monk]

There is a "shim club" here where you might be able to get supply. What I would suggest is that you buy one of the thinner shims such as a 2.35 or something as a spare. You can then use it to calculate the shims you'll actually need by rotating that shim in and back out of any valves that are tight.

There is no "normal". The most likely range is 2.45-2.65 in my experience but I've also seen valves outside of that in both directions.

Other than Z1 you really only have dealer supply or Ebay. Every now & again a full dealer "shim kit" comes up but usually for $250+

 

[cowboyup3371]

First check your clearances and verify what’s you have in the bike THEN order them if necessary. Depending on what is needed you may be able to move a few around and reduce the cost. However, DO NOT TURN THE MOTOR WITHOUT A SHIM IN EVERY LOCATION.

The Shim Club thread is here under GS Parts and Services: https://www.thegsresources.com/_forum/showthread.php?122394-GS-Valve-Shim-Club

 

[Guest]

Given that the bike is going on 40 years old, it is impossible to predict even within a range of several sizes what shims you should need. Although a given bike will need progressively thinner shims as the valves mash up into the head with use, anything could have happened between 1983 and now. For example, if the head has been off for service, a machinist who does not have a stockpile of Suzuki shims will just grind the tips of the valve stems down until he reaches the correct lash.

On top of that, there is no telling the sizes of the shims that the bike left the factory with or how much the valves have mashed into the head.

Anything anybody could say would be a blind guess. You just have to measure your lash, pull the shims, do the arithmetic, and get the shims you need.

 

[Steve]

Most of these bikes left the factory with shims in the 2.65 to 2.80 range. As the valves and seats wear, the clearance will go down, requiring thinner shims. The number of miles the engine has been run might give you an idea how many sizes down from original, but since you don't have any idea what "original" was, you simply need to open it up, measure your clearances, then remove each shim ONE AT A TIME, record its size, then order replacements as necessary.

AND, ... to help you keep track of what is in your engine and also give you an idea what shims you will need, feel free to take advantage of the offer in my signature.

.

 

[jsandidge]

I have an 1983 gs850L .Can anyone tell me what shims are the most likely shims I may need when checking and adjusting the valve clearance. I would like to have an assortment on hand before taking it apart. Also where can I purchase these. Aside from z1. Thanks.

Another option (which I have used) is to see if a local shop will swap shims with you. Bring in what you won't be using, and swap for the sizes you need. Usually, you can move some shims around. Then you'll find you may only need 1 or 2. The times that I have swapped shims with the shop, they just blew the dust off their kit (they never have a need for it anymore) and made the swap at no charge. As stated, never rotate the motor without a shim in every bucket.

 

[Redman]

I called a big multi-line shop to ask if they stock the shims for 82 Suzuki, he said, "Yah, we got all kinds of them for all bikes".
So I went in, guy at the counter says "oh, those old quarter sized ones, naw, we dont stock those."

Other thing to be aware of, if a shop does have a supply of the "quarter sized ones", be sure it is the old Suzuki ones not the old kawasaki ones, they are about half millimeter diameter different, but would look a lot alike.

 

[chuck hahn]

Suzuki's are 29.5 MM. Another option is ....if you have access to a surface grinder they can be skimmed. They are fully hardened. BUT.....they must be ground with coolant flowing on them.

I have a bunch of thicker ones I was gonna send to Ray but he doesn't have a surface grinder. Would be nice to have someone grind me some "off" sizes like 263, 252,267,268.

 

[Steve]

Why go for the "off" sizes? :-k

They are going to change, anyway, so stick with stock sizing.

.

 

[chuck hahn]

Some times you drop one size and your past the prescribed .08 mm. So an off size will be optimal. Don't tell me you haven't had it happen .lol

 

[Steve]

OK, it's happened, but I'm not going to tell you about it. :-\\\

That is one reason that many of us willingly go up to 0.10mm.

It also helps to have a few "X" shims in stock. :encouragement:

The only 'bad' thing about the "X" shims is that you can't order them, you have to find them.
I have bought shims on eBay only because they had a few "X" shims in the bunch.

.

 

[Brendan W]

Yamaha are also 29.0. Got one in a bag of shims from a closing down sale.

 

[chuck hahn]

yes......but zook shims are 29.5

 

[jon]

Thanks. I'll see what they have

 

[jon]

Why go for the "off" sizes? :-k

They are going to change, anyway, so stick with stock sizing.

.

I dont understand what that means. I was under the impression that I would need to change them as needed or when the gas closes.

 

[Steve]

I dont understand what that means. I was under the impression that I would need to change them as needed or when the gas closes.

That was a response to Chuck Hahn, who was suggesting grinding them to custom thicknesses.

Yes, you will need to change shims occasionally.

Have you opened up your engine yet to measure clearances and inventory your shims?

.

 

[jon]

No I haven't. I am planning to ride the rest of the season then do the job . Possibly have the whole motor gone threw. I was just hoping there was a kit or a certain number of shims I could purchase that would cover most cases. Also I did try my local dealer and they dont have any. In fact they brought out 4 boxes of very small in diameter shims like 7.3 or something and when I questioned the sizes said shims are shims. After a a quick conversation we came to agree that they just didn't have what I needed.

 

[jon]

Also is hitting quick reply the best way to reply to specific people ,as in these replys?

 

[Rich82GS750TZ]

Also is hitting quick reply the best way to reply to specific people ,as in these replys?

Quick Reply keeps the conversation going, but if you want to be specific about whom you are addressing, it sometimes help to use the Reply with quote on the bottom of the post you want to respond to. That's what I did here.

 

[Steve]

Also is hitting quick reply the best way to reply to specific people ,as in these replys?

Hitting the "Reply" button is pretty much the only way to respond. However, if the thread is really busy, with many different posters, you might want to go back to the post you are replying to and hit the "Reply With Quote" button. That will copy their post, then you can enter your reply. NOTE: if the quoted post is very long, possibly with several other points, you can edit out the irrelevant stuff and leave just the point to which you are replying.

Back to your valve shims: go back and re-read the replies in posts 2, 3, 4 and 5. There were no "standard" shims in the engine when it left the factory. Due to production tolerances, there were variations in the clearances, which required different shim thicknesses. It was common to find shims in the 2.65 to 2.80 range, but there is also no way to know if they have been changed since new. As an engine wears, the required shim thickness will decrease, but until you open up your engine, measure your clearance, then remove the shim to see its size, you will have no way to know what shim needs to be in there.

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