• 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...

  • 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.

Clearance issues! Tricky question! Need some help.

  • Thread starter Thread starter BigDaddyD
  • Start date Start date
B

BigDaddyD

Guest
So I finally tore into my top-end to check my valve-tappet clearances.
Here are the measurements I got... but there's a catch!

Cylinder 1 Exhaust: Feeler gauge= 0.038mm / Tappet 2.90
Cylinder 1 Intake: Feeler gauge= 0.051mm / Tappet 2.80

Cylinder 2 Exhaust: Feeler gauge= 0.038mm / Tappet 2.90
Cylinder 2 Intake: Feeler gauge= 0.063mm / Tappet 2.85

Cylinder 3 Exhaust: Feeler gauge= 0.038mm / Tappet 2.85
Cylinder 3 Intake: Feeler gauge= 0.051mm / Tappet 2.90

Cylinder 4 Exhaust: Feeler gauge= 0.038mm / Tappet 2.80
Cylinder 4 Intake: Feeler gauge= 0.038mm / Tappet 2.85

So... the catch is... my feeler gauges only went down to a .038mm
I looked all over town for smaller ones and couldn't find any.
BUT! The .038mm wouldn't fit, the clearance was too small. This mainly occurred with the exhaust valves, the intake valves clearances were between .038 and .063, so I should be ok there.
So if it says .038mm on my exhaust measurement, that means that the feeler gauge wouldn't fit.

So since the .038mm is close to being out of spec, should I replace those exhaust tappets with thinner ones to open up the clearance a little or am I safe??

I measured all the clearances twice, once at 90degrees and once parallel to the cylinder, just to be sure. I also measured the tappets with a digital caliper gauge since most of the numbers were wore off.

Thanks!
D.
 
Bikemaster sells a feeler guage set with the .010 increments. Maybe a local bike shop or dealer carries them. Maybe someone else can also chime in but I would change all of the exhaust shims and re-measure. Maybe change the #4 intake shim and re-measure and if it ends up over tolerance change it back unless you can get some of the half shim sizes. Looser is better than tighter, especially on the exhaust side.
 
Yeah, I checked around my area, went to autozone, sears, the suzuki dealership, and a few other local bike shops and NOBODY carried feeler gauges smaller then .03mm... it was ridiculous!
 
.03mm is .001", or half the thickness of a human hair. You won't find feeler gauges thinner than this and if you were to, they would tear in very short order.

Sounds like you need a thin "checking shim"; install the thin shim and then measure the clearance. After this you can calculate the proper shim thickness for your engine.

Regarding your checking method, the proper procedure is listed in the Factory service manual. If you do not follow the proper procedure the adjacent valve will be pushing up on the cam and skewing it in the journal clearance, thus leading to inaccurate readings. This is not a critical detail but worth paying attention to to assure the best results.
 
Last edited:
I used a Clymer's manual for the procedure, plus the GS750 manual found on Basscliff's website.
 
I ran into the same problem finding a proper feeler guage when I had my GS1000. I don't remember the clearance spec. (.001" sounds familiar) but I do remember that I acquired some machine shop shim stock of .001" and used it as a feeler guage. I would just cut another piece when the one I was using got beat up.

.038mm = .00149" .001" = .0254mm

I believe I could find some shim stock(free) and mail it to you if you would like.

Don
 
Hi Mr. BidDaddyD,

My feeler gauge goes down to .04mm. It that one doesn't fit, I pop in a smaller shim and re-measure. Simple as that. I got my feeler gauge at my local Pep Boys. You can also find them online very easily. I would get way too confused if I used an SAE feeler gauge. :-k

I'm sorry you missed my "garage day" last month. Mr. Gixxer Dan got a lesson on valve adjustments.

Thank you for your indulgence,

BassCliff
 
Nessism said:
Did you check the valves in adjacent pairs or one at a time?
Click to expand...

Both. I checked and re-checked them each a few times.
The manual on Basscliff's site explained how to check 2 at a time. And my Clymer's manual explained 1 at a time. So I checked both ways and got the same measurements.

So weather or not my feeler gauges go small enough, wouldn't putting a smaller shim in where it wouldn't fit bring it closer to spec with the intake valves?

I guess that's my question... even though my gauges only go down to 0.038mm the spec range is 0.03mm thru 0.08mm, so I'm at the tail-end of the spec range anyway.
So since my .038mm gauges won't fit the exhaust valves, putting in a shim the next size down will bring the clearance into the spec range, right?
 
BigDaddyD said:
I guess that's my question... even though my gauges only go down to 0.038mm the spec range is 0.03mm thru 0.08mm, so I'm at the tail-end of the spec range anyway.
So since my .038mm gauges won't fit the exhaust valves, putting in a shim the next size down will bring the clearance into the spec range, right?
Click to expand...

Hi,

Yes, that's the principle. Your .038mm feeler is near the tight end of the spec. The .051 and .063 are about in the middle. I even run a little looser than spec sometimes, up to 0.10mm, because I'd rather run loose than right at the bottom of the spec.

It sounds like you've just about got your valve check licked. Nice work.


Thank you for your indulgence,

BassCliff
 
Sometimes the valve seating further into the valve seat will require you to use a smaller shim. It depends what wears. Ideally, the shim wears and everything else stays the same.
 
You may have to go down two sizes, no way to know until you can get a thinner shim in there and measure again.
 
Nessism said:
You may have to go down two sizes, no way to know until you can get a thinner shim in there and measure again.
Click to expand...

Would using the method Basscliff explained help, popping in one of my smaller shims to get a measurement?
 
BigDaddyD said:
Would using the method Basscliff explained help, popping in one of my smaller shims to get a measurement?
Click to expand...

Without smaller feeler gauges that's the way it has to be done (to be done right)...Whenever your smallest gauge doesn't fit, there's no telling what the clearance is--could be .03mm or 0mm or even -2mm.
 
Do the clearances need to be the same between all the valves or just with in spec?
 
Within spec is fine for your clearances. As Basscliff mentioned looser is better than tighter on the clearances within the spec range.
 
BigDaddyD said:
So since my .038mm gauges won't fit the exhaust valves, putting in a shim the next size down will bring the clearance into the spec range, right?
Click to expand...

Correct only if there is at least some clearance. With the cam in the position that you would check the clearance see if you can easily rotate the shim and bucket, if you can that means you are somewhere between .000 and .038. Installing the next size shim would put you somewhere between .05 plus what ever your clearance is. If the clearance was .03 or higher it could put you slightly loose but you should check the clearance when finished anyway, but you'll probably be OK. If the the shim and bucket is tight and won't turn you need at least 2 sizes smaller or more just get a measurement, this is where it would be good to have a thinner reference shim.
 
Last edited:
zathros said:
Ideally, the shim wears and everything else stays the same.
Click to expand...
If the shim wears, you have problems. :eek:

The shims are heat treated and are harder than the cams or the bearings, so they should NEVER wear.





BigDaddy,
Now that you have done all the work, how are you going to record your results? :-k

Send me an e-mail (not a PM) (click on my name for e-mail address info) with a request and I will send you a copy of my spreadsheet that will help you figure out what size shim you need and will also help keep track of what you have in there from one service interval to the next. 219 satisfied users so far, you could be #220. :o

.
 
New Problem! Which way is right??

New Problem! Which way is right??

Ok...
So today I used Basscliff's method of replacing my shim with a smaller one to measure since my gauges don't go low enough.
And my measurements were all over the place! So I went back and re-measured everything!

I'm probably over-doing it... but I've been measuring each valve with the lobes at 90-degrees to the cylinder AND 0-degrees (aligned with the cylinder)..

So what is the correct way to measure?
The Clymer's maunal says to measure with the lobes at 90-degrees, but the manual I downloaded from Basscliff's site says to measure 2 lobes at once. Exhaust 1 and 2 when 1 is at 0-degrees and 2 is at 90-degrees and so on.

I've followed both techniques and have gotten different measurments.
So now what?

Please help!
Thanks!
 
BigDaddyD said:
Ok...
So today I used Basscliff's method of replacing my shim with a smaller one to measure since my gauges don't go low enough.
And my measurements were all over the place! So I went back and re-measured everything!

I'm probably over-doing it... but I've been measuring each valve with the lobes at 90-degrees to the cylinder AND 0-degrees (aligned with the cylinder)..

So what is the correct way to measure?
The Clymer's maunal says to measure with the lobes at 90-degrees, but the manual I downloaded from Basscliff's site says to measure 2 lobes at once. Exhaust 1 and 2 when 1 is at 0-degrees and 2 is at 90-degrees and so on.

I've followed both techniques and have gotten different measurments.
So now what?

Please help!
Thanks!
Click to expand...


No disrespect intended Daddy, but if you would go back and read post #4 above, I tried to spell it all out for you then...

As stated above...

1) you need a thin "checking shim" (which you apparently got). Good work.

2) you need to check the valves per the Suzuki manual procedure. It is not as simple as setting the cam lobe at either 180 or 90 degrees. The cam needs to be appropriately positioned per the manual and the valves need to be set in pairs so the adjacent valve is not pressing up on the cam.

Crack out the Suzuki manual and use that thin shim of yours to get the true clearance. After you get the new shim installed, rotate the engine and double check the clearance. Keep going...
 
Last edited:
You must log in or register to reply here.
Back
Top