valve shims, where get the X sizes?

[Redman]

- I gather that the GS shims are the 29.5mm diameter.

- I see bike bandit lists shims (Suzuki OEM I assume, and does not stat the diameter) for about $12 a piece.

- I see that Z-1 has the 29.5mm shims that state in description are for various Suzuki GS's. And I gather their shims are the an aftermarket brand (same as the kits I guess, dont recall at the moment the name) but are just under $5 each. I would assume they are acceptable.

-I understand that don't really need the X sizes to adjust within spec (the spec range is .05 wide, and the standard step of the shims is .05). Only really need them if want to have all the clearances adjusted to all be about the about the same portion of the range, say want them all "loose" in the upper part of the range, or maybe want them all in the middle part of the range, or want them all in tight part of the range so open valve that little bit more. (am not intending for this to be a disscussion of if should be loose or tight or either).

- And I understand that X means half size, that means for example; that a 255X is not 2.55mm but is about half way to the 260, so about 2.57mm (2.575 maybe).

All the above is not a question, but I state just for verification.

My question is: Where does one get the X or half size ones?

None of the several places I looked listed any X size. Although on the OEM fissche (82 1100G) there did seem to be two part numbers listed for each size, but the descriptions where the same for each of the two part numbers per size, maybe the X got truncated off the description of one of the two (or maybe I am missing something else).

Again, asking who carrys the X sizes (and for a good price to buy a handfull, not an entire kit).

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<<<Later note, or story of my ignorance:
I did not know about these X sizes a couple years ago when I did a valve clearance adjustment. Which might explain why I had some trouble when I measured my clearance(s), took out the existing shim(s), and ordered replacement shim(s), installed the new shim(s). And some of the clearances did not come out to what I was expecting (yes, I rolled the engine over a few times to squish out oil and settle things). Now I see that some of the shims I took out a couple years ago where the X's, and I did not know what that meant at the time.

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[mike_of_bbg]

Yeah, the x sizes are .02-.03mm larger than the non-x. Unfortunately, nobody that I know of sells the x sizes - and that's been pretty consistent across all the vendors and threads on the subject I've looked at. You can check with local mechanics or shops to see if they have any x's for exchange, or get in touch with the shim club.

I have a couple of 2.7x shims if you're interested (they mic out to 2.73). PM me if you want 'em.

 

[rustybronco]

http://www.thegsresources.com/_forum/showthread.php?t=122394

CURRENT INVENTORY

2.15=0 2.16=0 2.17=0 2.18=0 2.19=0 = 0
2.20=4 2.21=0 2.22=0 2.23=0 2.24=0 2.25=0 2.26=0 2.27=1 2.28=1 2.29=0 = 6
2.30=7 2.31=0 2.32=0 2.33=0 2.34=1 2.35=2 2.36=0 2.37=1 2.38=2 2.39=0 = 13
2.40=6 2.41=0 2.42=0 2.43=0 2.44=1 2.45=2 2.46=0 2.47=0 2.48=0 2.49=0 = 9
2.50=6 2.51=1 2.52=0 2.53=0 2.54=2 2.55=5 2.56=2 2.57=2 2.58=6 2.59=4 = 28
2.60=38 2.61=7 2.62=7 2.63=11 2.64=7 2.65=26 2.66=9 2.67=0 2.68=3 2.69=20=130
2.70=8 2.71=3 2.72=3 2.73=7 2.74=19 2.75=18 2.76=1 2.77=4 2.78=3 2.79=4 = 69
2.80=17 2.81=1 2.82=0 2.83=1 2.84=12 2.85=12 2.86=0 2.87=0 2.88=0 2.89=0 = 43
2.90=7 3.05=2 = 9
TOTAL SHIMS = 317

 

[Nessism]

If you have a micrometer (calipers are not accurate enough for this kind of check) and measure the shims you will find that they vary in thickness. Lacking X shims this is your best chance to get the clearance exactly where you want them.

 

[Steve]

As noted above, you can not order X shims from a store. You pretty much have to "luck" into them by watching eBay for shims, getting a new head that still has shims, finding a friend that has some, contacting the GS Shim Club, whatever.

I have used the shims from Z1 with no problem. Can't say they are of any less quality. In fact, the only thing I have noticed that is different is the edge of the shim. OEM shims have a bit of a chamfer, the Z1 shims have a square edge. The price is right (currently just over $5, at $5.28) and service is quick. Just can't beat that combination.

As far as clearance, yeah, technically anything within the stated specs is good. After all, that's why the specs exist. In practicality, adjusting toward the looser end or just barely outside spec will give longer service intervals. If you are racing, keeping them at minimum specs will maximize valve lift for more air flow, meaning more power. Loosening the valves a bit will reduce peak power ever so slightly, but will move the torque peak a little lower in the powerband, which makes it a bit friendlier for street use.

One other possible source of X shims is your local Suzuki shop. See if you can sweet talk the parts person or the old mechanic into checking their parts box. They usually have a box of "old" shims that they sometimes use when doing a tune-up on a bike.

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[salty_monk]

I have no probs getting accurate measurement on these with calipers...

but then I have a very expensive set of Japanese calipers not your $9 Harbor freight jobs...

Dan

 

[rustybronco]

I have no probs getting accurate measurement on these with calipers...

but then I have a very expensive set of Japanese calipers not your $9 Harbor freight jobs...

Dan

I 2nd that.
I have an older set of these http://ep.yimg.com/ca/I/pgiinc_2086_34114381

 

[salty_monk]

Snap. Mine are Mitutoyo too but mine are the digital ones. I acquired them from a previous job.

Dan

 

[mike_of_bbg]

I have a cheap, chinese-made digital caliper - but it was dead on with the micrometer when I measured all my shims. They were both within .01mm of the printed size.

 

[Redman]

-
...
...
asking who carrys the X sizes
...
....

So, if I Understand properly: the answer to "where" to order the X size shims is "nowhere".
They are not sold thru suppliers. Appartently Can be found only by someone who has taken one out of an engine. So, then, it seems that any X size shim must be a factory stock installed shim.

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[Steve]

Yep, yep, and you're right.

.

 

[lurch12_2000]

So, if I Understand properly: the answer to "where" to order the X size shims is "nowhere".
They are not sold thru suppliers. Appartently Can be found only by someone who has taken one out of an engine. So, then, it seems that any X size shim must be a factory stock installed shim.

.

I've had more than a few X sizes in my hands for the 8 valve bikes I've adjusted, but have freely traded some of them off for regular sizes either at the dealer or here on the forum.
If they're discontinued and "collector's items" then maybe I should have asked for 2 in return?
Anyway, I usually can match regular sizes up fine with a little shuffling to get somewhere between .038(my smallest feeler gauge) - .09mm (slightly over spec).

 

[bwringer]

So, if I Understand properly: the answer to "where" to order the X size shims is "nowhere".
They are not sold thru suppliers. Appartently Can be found only by someone who has taken one out of an engine. So, then, it seems that any X size shim must be a factory stock installed shim.

.

Yup, that's it -- they were installed only at the factory. I suspect it's mostly Suzuki's way of using up out-of-spec shims. But if you have a good selection of them, they're nice to use sometimes. As you saw in my shim kit, I've collected quite a few over the years.

On later engines, like the GS500, these shims are marked with a measurement instead of an "x"; for example, "2.78" instead of "2.75x".

When in doubt, go with the smaller shim/bigger clearance. I've set clearances as high as .13mm (about .005") before (didn't have the size I needed at the moment) with no detectable added noises or problems. Keep in mind that GS valve clearance specs are extremely small compared to most engines.

 

[Redman]

....
.....
As you saw in my shim kit, I've collected quite a few over the years.
....
....

Yep, Brain, I saw that, the kit was nice. And I thank you. I would have mentioned it more specifically sooner, but was not going to advertise this kit. Sure was nice to just have what size was needed right there on the spot, rather than have to order and wait several days (like I did a couple years ago).

Saturday, I added the 5 or 6 (that I had from a couple years ago) to the kit.

And then later I (should say "we") swapped out 3 from the bike that needed to be adjusted. And in doing so depleted the kits supply of two different sizes, and are two other sizes that the kit did not have.

And, of the four sizes missing, two are the X size. BUt now that I review my notes, it was not the X sizes that I took out of the kit. Okay, I feel better now.


.

 

[Redman]

Yep, yep, and you're right.

.

Thanks.

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[Steve]

Keep in mind that GS valve clearance specs are extremely small compared to most engines.

Well, at least they are at the temperatures where we measure them.
What is the actual clearance at operating temperature? How does that compare with other bikes? Kinda hard to say.

I know that the clearances on the Kaws that I had were .008" for the intakes and .012" for the exhausts. How much that changed at operating temperatures, I don't know, but I do find it interesting that the clearances were the same for the air-cooled bikes I had and the water-cooled ones.

Is it possible that, due to metal expansion, the angles involved and the amount of material, that the clearance on Suzuki valves grows to be about the same as the Kaw valves when they are both at operating temps?

I have no idea, but it's nice to know that others also operate at the larger end of the clearance specs.

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