• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • This forum is to be used by folks who sell parts or services for GS series motorcycles regularly, or as a business.

    If you are interested in providing parts and/or service to GSResource members it is expected that you will 1) keep customers informed on the status of their order, 2) you will reply to customer emails and PM's in a timely manner, 3) you provide what is agreed to in a timely manner. If personal circumstances prevent you from doing this, then you are expected to inform the customer before any transaction takes place. Failure to follow these basic business rules will force me to ban your forum account and list you in the Deadbeat forum.

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

GS Valve Shim Club

  • Thread starter Thread starter Guest
  • Start date Start date
220 is as thin as they go. The only way i know of to get things into using a THICKER shim is to top the valve stem itself. Every two thousands thats taken off ADDS 1 shim size. So if say your right at 220 now then taking two thousands off will make the shim needed a 225 and so on. Note that you CAN NOT take off so much you get down to the retainers. You need 10 thousands or more above the retainers so the bucket presses down only on the valve stem itself, If you look inside a bucket youll see the round mark the valve stem leaves.
 
I have a 2.15mm shim that is used in situations where I'm getting zero clearance. Then I can use thicker feeler gauges to get into the ballpark. You can get Suzuki OEM shims down to 2.15mm: https://www.onlinecycleparts.com/oem...-tappet-t-2-15

That said, if a 2.20 or 2.15 shim is still not thin enough, the head is coming off to see what's happening and address it. (You can also get a look into the cylinder with a cheap "endoscope" camera through the spark plug hole, and push the valve down to get a look at the edge.)

Clearance that small indicates a problem, or at least advanced wear, such as a burned valve, a valve that's too worn (the edge will be sharp instead of square), or perhaps even a "tuliped" valve. I don't think I've seen a "tuliped" valve in a GS, but I have seen the former two issues.

This can also happen after grinding or cutting the valve seats; it's pretty common to need to "tip" the valves as Chuck describes after this kind of work. Lapping the valves and seats doesn't cause much, if any change in the clearances, but grinding or cutting removes a lot more material.

On higher mileage bikes, the inner two exhaust valves see a lot more heat, and are the first to wear down to a sharp edge. New OEM valves are usually NLA, but it's not too terribly difficult to find good used valves from the outer two cylinders on a lower-mileage junkyard bike. The valve seats are extremely tough, and even if the valves are burned (usually because of leaking intake o-rings) the valve seats are usually fine.
 
Last edited:
bwringer said:
I have a 2.15mm shim that is used in situations where I'm getting zero clearance. Then I can use thicker feeler gauges to get into the ballpark. You can get Suzuki OEM shims down to 2.15mm: https://www.onlinecycleparts.com/oem...-tappet-t-2-15

That said, if a 2.20 or 2.15 shim is still not thin enough, the head is coming off to see what's happening and address it. (You can also get a look into the cylinder with a cheap "endoscope" camera through the spark plug hole, and push the valve down to get a look at the edge.)

Clearance that small indicates a problem, or at least advanced wear, such as a burned valve, a valve that's too worn (the edge will be sharp instead of square), or perhaps even a "tuliped" valve. I don't think I've seen a "tuliped" valve in a GS, but I have seen the former two issues.

This can also happen after grinding or cutting the valve seats; it's pretty common to need to "tip" the valves as Chuck describes after this kind of work. Lapping the valves and seats doesn't cause much, if any change in the clearances, but grinding or cutting removes a lot more material.

On higher mileage bikes, the inner two exhaust valves see a lot more heat, and are the first to wear down to a sharp edge. New OEM valves are usually NLA, but it's not too terribly difficult to find good used valves from the outer two cylinders on a lower-mileage junkyard bike. The valve seats are extremely tough, and even if the valves are burned (usually because of leaking intake o-rings) the valve seats are usually fine.
Click to expand...

That is some invaluable information. So my head was serviced my a shop, and now my exhaust side seems to be way off. I tried and ground one old shim down to 180-185 and it still seems as not thin enough. The shop did not mention any excessive wear on valves or valve seat. I am going to contact them next week and ask for more information or any advice. That’s really worrisome.
 
GS valves cant be ground far as ive bben able accertain. No info in service manual. As i stated above you can top the stems but be sure to stay 10 thousands or so above the keepers. And for every 2 thousands thats removed equals one shim size. Wish i had a part number for the seats but maybe someone here has that info. If so please pass it along.
 
chuck hahn said:
GS valves cant be ground far as ive bben able accertain. No info in service manual. As i stated above you can top the stems but be sure to stay 10 thousands or so above the keepers. And for every 2 thousands thats removed equals one shim size. Wish i had a part number for the seats but maybe someone here has that info. If so please pass it along.
Click to expand...

Suzuki doesn't sell valve seats. It may be possible to replace them with an aftermarket part, but the cost will exceed purchasing a serviceable head.

Jay, owner of APE, mentioned on the KZ site, that they tip valves and even keepers sometimes, to keep the head in service. I don't know the limits, but there are ways to keep even a worn head out of the scrap bin without changing seats.
 
True enough ED. There has to be a good 30 thou above the top of the keepers so for each 2 thousands vequalling one shim size you can take a heck of a lot off before getting to keepers. The idea is to keep the stem above the top of the keepers so the bucket doesnt hit them and throw them out. I CRINGE at the thoight of hearing that happen!!!!!
 
Please pardon my ignorance but I am not quite familiar with the glossary here:
what is keeper? What means tipping valve?
also, is there a way to measure the clearance between an empty bucket and cam? Running the engine with exhaust side out of specs - what are the consequences?
 
keepers are the half moons that fit into the groove at the top of the valve stems... a wedge that KEEPS the top cap locked in place trapping the springs. TIPPING OR TOPPING is removing material from the top of the valve stem making it shorter, Thus making bit shorter increases the gaps when measuring between a shim and the cam shaft. So if youre already at the lowest shim made then tipping the stem will now allow the use of a thicker shim. And as i stated, every 2 thousands taken off adds 1 shim size. Example... If say your at ,03 MM clearance with the 2,15 shim in the bucket. So you take 2 thou off the stem..you now have the clearance to put in a 2.20 shim
BUT whenever i have a stem ground i usually take 10 thou off which lets me now use a really thick shim and this then allows me to just resume normal clearance checks and know i have plenty of other shims that will fit when te time comes. make sense to you?
 
chuck hahn said:
keepers are the half moons that fit into the groove at the top of the valve stems... a wedge that KEEPS the top cap locked in place trapping the springs. TIPPING OR TOPPING is removing material from the top of the valve stem making it shorter, Thus making bit shorter increases the gaps when measuring between a shim and the cam shaft. So if youre already at the lowest shim made then tipping the stem will now allow the use of a thicker shim. And as i stated, every 2 thousands taken off adds 1 shim size. Example... If say your at ,03 MM clearance with the 2,15 shim in the bucket. So you take 2 thou off the stem..you now have the clearance to put in a 2.20 shim
BUT whenever i have a stem ground i usually take 10 thou off which lets me now use a really thick shim and this then allows me to just resume normal clearance checks and know i have plenty of other shims that will fit when te time comes. make sense to you?
Click to expand...

Yes, understood. What it the process of tipping the valves? How is it typically done?
 
Surface grinder, lathe, or a valve grinding machine like my buddy has. They gotta be ground at an exact 90 to the stem itself.
 
There's a larger point here: if you're out of shim room, SOMETHING AIN'T RIGHT. Tipping the valves isn't going to fix anything; you need to figure out what's going on here.

You can start by taking a look at the entire perimeter of he valve with a bore scope and/or pulling the head off to see what's going on.

The only circumstance where tipping the valve would make any sense is if the engine has been apart before and someone went too far with a valve seat grinder. (And that's assuming the grind was otherwise done competently... often not a safe assumption.)

You can't tip the valve in situ, so you're really not in for any more work to go ahead and pull it off and see what's wrong. Again, SOMETHING IS WRONG. Tipping is a workaround for a very specific and frankly unlikely situation.

My bet would be that this valve is burned; its probably got a gully worn into one edge by hot gasses. At the very least, it's worn to a knife edge. Either way, it will need to be replaced, the valve seat carefully inspected, and the valve and seat lapped.
 
Is the Shim Club dead? It seems that Ray hasn't been back to GSR for a year. Does anyone have any recent experience?
 
I PMed him about a year ago willing to donate about 30 shims i have on hand but never got a response. I wish i had the time to take up the club as it was a great resource i had used countless times. I now have access to a surface grinder so i can pretty much make what i need. Has anyone ever texted the rockwell on a shim befor and after surface grinding to determine if the grinding affects them?? Just curious about that aspect
 
I could be mistaken but I believe I read here somewhere that Rapid Ray was removed from the forum a few months ago. My apologies to Ray if I’ve got my facts wrong.
 
Rich82GS750TZ said:
I could be mistaken but I believe I read here somewhere that Rapid Ray was removed from the forum a few months ago. My apologies to Ray if I’ve got my facts wrong.
Click to expand...

Different Ray. Shim club Ray = Ghostgs1. Rapidray = banned dude.
 
bitzz said:
Pretty sure they're case hardened, otherwise they'd shatter
Click to expand...

Steve (IIRC), posted a pic of a shattered one which seems to tally with them being through-hardened.
Under normal conditions they're not seeing an impact, just a steep rise/fall in pressure.
 
Grimly, im no metal expert but if they were just case hardened wouldnt it stand to reason that given the cam lobes sweep across the face that the shim would start to take on a dished (think banana) shape over time???
 
I usually measure my shims with a digital caliper, but if i measure using an outside micrometer i do find small differences in outside rim and the contact area with the lobes.
 
chuck hahn said:
Grimly, im no metal expert but if they were just case hardened wouldnt it stand to reason that given the cam lobes sweep across the face that the shim would start to take on a dished (think banana) shape over time???
Click to expand...

If just case hardened that would be fairly disastrous at some point, when the case hardening wore through.
I wonder if the aftermarket ones are fully hardened or case hardened. Just another thing to worry about, but next time I'm setting them I'll do like Rijko and perform some accurate measurements.
 
You must log in or register to reply here.
Back
Top