Valve shims

[Guest]

I have a 1981 suzuki gs550t and I am in serious need of valve shims so i can adjust my valve clearances. please let me know of where I can buy these shims, I've e heard theres kits that contain all sizes which id prefer. But I am also aware of the shim club among forum users. Sadly I am not familiar with how it works. Any info on anything is greatly appreciated.

 

[fastbysuzuki]

Look at post #1 here https://www.thegsresources.com/_for...-GS-Valve-Shim-Club/page6&highlight=Shim+club

pm Ghostgs1 first to check things are still the same. Being in the uk unfortunately we don't have access to this great service :upset::upset::upset:

 

[Steve]

First of all, do NOT get a kit. :-k

Yes, they contain a couple of each size shim, but at least half of them are useless. As the miles go on, the valves and/or head wear a bit and clearances tighten up. That means you will always need thinner shims, so any shims in the kit that are larger than what you already have are useless. When these bikes left the factory, the shims were at about 2/3 through the size range. The only time you <might> need them is if you have some head work done AND trim a bit off the ends of the valves.

Contact ghostgs1 to see how the shim club works. If this is your only GS and you don't plan on getting another, this is a great, low-cost way to go. If you plan on another bike (or three), you might want to consider buying shims and building your own reserve. Shims are available for about $5 each from Z1 Enterprises.

Which sizes to order? Do NOT order any until you know what you need. And, you may be able to move some around to a different valve to reduce the number you need. First, you need to determine what your clearances are and what sizes you have now, so you can calculate what you need. To help with that calculation, feel free to take advantage of the offer in my signature.

It is not just 'important', it is CRITICAL that you follow the correct procedure for checking clearances. The pictures in all three manuals (Suzuki, Clymer, Haynes) are confusing, but the text in the Suzuki manual explains it quite well.

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[alke46]

And just to add to Steve's advice, never under any circumstance should you rotate the engine without a shim in the bucket. If necessary to do this, place a quarter in the bucket so you don't damage the finish on the cam lobe.

 

[Guest]

you can try PM to Ray but I had better luck with sending him an email, which can be found by viewing his email address...'send email'
I have several shims to send back to him but I suspect they will all be too big for your uses.

From what I gather it's not the shims wearing thinner (although they do get thinner with use) that is the reason for changing shims, but the wearing of the valve seat surfaces that cause the valve stem and thus the bucket to move 'up' that causes the clearance to get thinner. putting in a thinner shim optimizes the contact time between the lobe and the shim and keeps the valve open the optimal time, but the wear of the surfaces of the valve seat are unavoidable and not corrected by changing shims.

it's kind of a 2 week process of taking the tank off...taking the valve cover off....going through the process of checking the clearances you currently have, likely you will not have the feeler gauge thinner than .04mm, so you will have to guess about true clearances. You can get creative by finding a thin shim in a bucket and then experiment by moving it around to other buckets and getting some idea of what changes happened with the clearance so you can deduce what clearance you had. But that's not perfect since the shims haven't totally seated when all you do is rotate the engine by hand.

So, you have to figure out the exact clearance you have...plus the exact shim width you have in each bucket (imprinted on the back of the shim). Then your goal is to find a shim thickness that gets you in the ballpark of 0.03-.08mm up to .10mm+- .02mm by changing shim thickness. and since you are ordering through the mail any mistake will cost you a week to correct.

Those shims are the ones you are going to order from Ray, my local Suzuki dealership wanted $15 each...Ray got me in the door for half that and I had to replace 8 of 8 shims since they were original and I had zero clearance (.00mm) on 7 of 8.

Ray was prompt in shipping but it still takes time and you have to decide if you want to reassemble the valve cover to ride it for the intervening time...which means securing the valve cover with the old gasket, etc...then taking it all apart again to replace the shims when they arrive. It would be easier to own a huge shim kit but like others said, it's not worth it unless you own 10 Suzukis from the '80s.

I elected to leave the cover disassembled since the clearances were zero and it was obviously heat scorching the cam lobes whenever I had it running.

I got good with two small hooks in retrieving the shims, but it did feel a bit ridiculous trying to fish them out of a pool of oil under a cam lobe in the shadows with two hooks. I felt using a magnet was too risky because it 'could' magnetize the shim. It was NOT easy with the first shims I got out, and the thickness markings were obliterated on several of them which made it even more difficult to figure out what thickness shim I needed since I didn't know what I had (this involved shuffling around shims that I knew the thickness of). Just one spare shim would've helped to start.

The valve depressing tool was essential and one trick that I learned was that the tool holds the shim down perfectly well without me holding the tool. At first I was trying to retrieve the shim with one hand because I thought the pressure would toss the tool off, but it's not true. If the tool is seated well on the edge of the bucket it will stay depressed and you can use two hands to get the shim, and you will need both hands.

Refer to the manual for the proper position of the lobes and then use the tool.

I did get careless once and started to rotate the engine with the depressing tool still under the cam shaft...trying to work too fast.

I reused the valve cover gasket but I have a spare if it had leaked. I also reused the half moon cam plugs since they weren't leaking, but I have spares if they do leak.

It's a process but definitely essential infrequent maintenance. From what I've read, they keep their clearance for a long time. I was waiting on other parts so it took 3 weeks to get it running again.

If you haven't done this before feel free to explain how you are getting the clearance numbers and the thickness of your current shims so someone here can double check your process. A couple of videos out there are pretty bad. There is a cylinder order you go in to reduce extra labor with rotating the cam lobes. I aimed for .10mm clearance and that's about what I got but I agonized over it since I had zero clearance and if I skipped one shim size I wasn't sure if I would get it and if I just went one size thinner then I could easily get .04mm which is the lower end of in spec. and would require maintenance sooner.

 

[Grimly]

I got good with two small hooks in retrieving the shims, but it did feel a bit ridiculous trying to fish them out of a pool of oil under a cam lobe in the shadows with two hooks. I felt using a magnet was too risky because it 'could' magnetize the shim. It was NOT easy with the first shims I got out, and the thickness markings were obliterated on several of them which made it even more difficult to figure out what thickness shim I needed since I didn't know what I had (this involved shuffling around shims that I knew the thickness of). Just one spare shim would've helped to start.

A pair of these, makes it a breeze.

 

[Steve]

This is a perfect example of why you need to pay attention to details. :-k

..., likely you will not have the feeler gauge thinner than .4mm, so you will have to guess about true clearances.

I'm sorry, but if you don't have a feeler gauge thinner than point four mm, you have no business even thinking about doing this job. The clearance you are looking for is one-tenth of that, or point ZERO four. Actually, it's point zero three to point zero eight, but the four is in that range.

Then your goal is to find a shim thickness that gets you in the ballpark of 0.3-.08mm up to .10mm+- .02mm by changing shim thickness.

Again, zero point three mm is WAY too large a clearance, you are looking for a maximum clearance that is about one fourth of that. Yes, it is possible to go up to .10mm of clearance, but I would be leary of that ?0.02. The minus part of that would put you right at the upper end of the specified clearance, but the plus part starts putting it almost one full shim size out of the proper range.

The details I am pointing out above are the number of zeros that were mentioned. It gets even more interesting if you have Imperial (Inch) feeler gauges. Using those, your clearance range is 0.0015-0.003". What is critical here is that 0.003 is the maximum, but in metric measure, 0.03 is the minimum. PAY ATTENTION TO THE NUMBER OF ZEROS AND THE MEASUREMENT SYSTEM (especially when offering advice).

.

 

[Guest]

I have a 1981 suzuki gs550t and I am in serious need of valve shims so i can adjust my valve clearances. please let me know of where I can buy these shims, I've e heard theres kits that contain all sizes which id prefer. But I am also aware of the shim club among forum users. Sadly I am not familiar with how it works. Any info on anything is greatly appreciated.

GS500s were in production until 2009. I've had no trouble getting those shims from Suzuki dealers. There's no difference that I know of. Plus I know where they've been.