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Main Area => General GS500 Discussion => Topic started by: vorBH on April 13, 2010, 02:52:51 PM

Title: Valve Clearance
Post by: vorBH on April 13, 2010, 02:52:51 PM
Hi Guys

07 GS500 - ~20,000km
I don't think the valves have ever been checked. Is this really bad?

So..from this page: http://www.gstwin.com/adjust_valves.htm
I dont understand some things, VERY abrupt instructions.

1. The part where to remove the right Suzuki cover and locate the R and R-T marks...I dont, understand, what do you do here?...even the Haynes up 97' manual is not clear...How come Kerry doesn't do it in his video

The steps:
a) Remove right "suzuki" cover and locate the R and R-T marks. Align pick-up with R-T mark with a 19mm wrench
b) The marks on the camshaft should be facing one to another. If they are one opposite to another, turn the crankcase 1 complete turn and realign pickup to R-T

I dont understand...:S

2. Now also the Cam tension (I think thats what its called), do I need to check this? My buddy has supersport 636 and looks after it....what should I be doing the 500?

3. The 9th picture down the column...now actually check valve clearance....so setting engine in that position allows you to check BOTH intake valves at the same time? Or do you need to rotate the engine a bit, so that the lobe sticks up on the other valve??

4. VERY IMPORTANT - since I will be going under there and opening the bike up, valve cover - what OTHER maintenance should I perform under there? Any torque checks on cylinder heads? How to do this? Or anything else?
Title: Re: Valve Clearance
Post by: romulux on April 13, 2010, 04:08:44 PM
Quote from: vorBH on April 13, 2010, 02:52:51 PM
Hi Guys

07 GS500 - ~20,000km
I don't think the valves have ever been checked. Is this really bad?

So..from this page: http://www.gstwin.com/adjust_valves.htm
I dont understand some things, VERY abrupt instructions.

1. The part where to remove the right Suzuki cover and locate the R and R-T marks...I dont, understand, what do you do here?...even the Haynes up 97' manual is not clear...How come Kerry doesn't do it in his video

The steps:
a) Remove right "suzuki" cover and locate the R and R-T marks. Align pick-up with R-T mark with a 19mm wrench
b) The marks on the camshaft should be facing one to another. If they are one opposite to another, turn the crankcase 1 complete turn and realign pickup to R-T

I dont understand...:S

Could you be a little more specific about what's unclear?  Have you opened the side cover yet?  There are 3 bolts, just pop them off and take a look if you haven't yet.  That might clear things up.  There's a 19mm bolt that you turn.  While you turn it, an alignment mark will turn with the bolt.  That's turning the engine.  Line it up with the valve cover off the engine, watching the lobes.  When you line it up correctly, 3 lobes will point away from the engine up into the air.


Quote from: vorBH on April 13, 2010, 02:52:51 PM
2. Now also the Cam tension (I think thats what its called), do I need to check this? My buddy has supersport 636 and looks after it....what should I be doing the 500?

Not a bad idea to do so...I forgot to last time and I'm not too worried about it.


Quote from: vorBH on April 13, 2010, 02:52:51 PM
3. The 9th picture down the column...now actually check valve clearance....so setting engine in that position allows you to check BOTH intake valves at the same time? Or do you need to rotate the engine a bit, so that the lobe sticks up on the other valve??

Setting that position allows you to check both intake and one exhaust.  Then you rotate the 19mm bolt again and line it up for the last exhaust valve, and you check that one.


Quote from: vorBH on April 13, 2010, 02:52:51 PM
4. VERY IMPORTANT - since I will be going under there and opening the bike up, valve cover - what OTHER maintenance should I perform under there? Any torque checks on cylinder heads? How to do this? Or anything else?

Nothing high priority that I'm aware of.
Title: Re: Valve Clearance
Post by: vorBH on April 15, 2010, 07:41:10 AM
So understanding the mechanics here...that 19mm bolt behind the Suzuki cover...if ie) turning it clockwise tightens...like does it tighten it? Can it be overtightened...how much can I expec to be turning it...I'll have to open and see, but its weird to me that the slight turns there will actually turn the engine....And when go back to check the 1 left exhaust valve...should loosen it or something? (the 19mm)....and then after checking the left exhaust..line up the pick-up with R-T mark (or is that only done once)??

So is it as simple as, taking off the Suzuki cover...1) Align pick-up with R-T mark with a 19mm wrench..which will line up the marks on the camshaft...but if they are not it says "turn the crankcase 1 complete turn"...whats the crankcase? Just put in higher gear and turn rearwheel 1 turn maybe?  2) now that aligend at pickup and R-T mark..check valve clearances in intake and right exhaust 3) turn engine 1 turn (is that 1 complete turn of the wheel or something? How do you see the cycle of the engine?) 4) check left exhaust valve clearance
Title: Re: Valve Clearance
Post by: CliffHanger on April 15, 2010, 07:55:29 AM
Quote from: vorBH on April 15, 2010, 07:41:10 AM
So understanding the mechanics here...that 19mm bolt behind the Suzuki cover...if ie) turning it clockwise tightens...like does it tighten it? Can it be overtightened...how much can I expec to be turning it...I'll have to open and see, but its weird to me that the slight turns there will actually turn the engine....And when go back to check the 1 left exhaust valve...should loosen it or something? (the 19mm)....and then after checking the left exhaust..line up the pick-up with R-T mark (or is that only done once)??



You aren't tightening anything.
You are turning the engine over by turning the 19mm head.
Turning the engine also turns the camshafts... it is simply easier to do this than leave it in gear and turn the wheel.

Don't worry about the ignition pickup for the alignment, go with the camshafts.

Title: Re: Valve Clearance
Post by: vorBH on April 15, 2010, 07:23:40 PM
Hmm ok..But what is the second part? The ignition pickup? - I understand line up the camshafts..but what is the ignition pickup?

Is there somewhere I can read abotu all this...missing out on some terms...
Title: Re: Valve Clearance
Post by: Paulcet on April 15, 2010, 08:22:31 PM
Quote from: CliffHanger on April 15, 2010, 07:55:29 AM

Don't worry about the ignition pickup for the alignment, go with the camshafts.


He said:  "Don't worry about the ignition pickup for the alignment"

I think you will be fine if you just get into it.  Once the covers are off (the valve cover and ignition pickup cover) and you turn that 19mm bolt you will see what is going on.  Turn it.  When the notches on the camshafts are facing each other, stop.  Measure.  Turn the 19mm bolt one full turn (the notches will be facing away from each other), stop.  Measure.
Title: Re: Valve Clearance
Post by: Allen on April 16, 2010, 01:50:45 AM
First get everything off, also remove the spark plugs as it makes it easier for you to turn the engine.  As you turn the crankshaft with the 19mm, you will notice the camshafts rotating; the ends of the camshafts have a rectangular cut-out like a keyway, rotate the engine until these are facing each other, the left exhaust lobe should be facing directly down, and now you can measure the clearance on the right exhaust as well as the two intake clearances.  Now rotate the engine so the keyways are facing away from each other and measure the left exhaust.  If your bike was running poorly prior to this, you may have zero clearance on one or both exhaust valves, try to fit your slimmest feeler, if it doesn't fit try to rotate the bucket with your finger, if it rotates then it has at least some clearance. Good luck, hope it helps.
Title: Re: Valve Clearance
Post by: Allen on April 16, 2010, 01:56:34 AM
I think the ignition pick up that you are refering to is the metal disc that you are using the 19mm wrench to turn, when you position the camshafts to check clearances take a look at the orientation of that disc, as it turns there are times when it touches a metal prong and times when it doesn't, I think this has to do with the timing of the spark, (I think). Run your bike in the dark with that cover off and you will see what I mean. :cool:
Title: Re: Valve Clearance
Post by: vorBH on April 16, 2010, 09:27:19 AM
Thanks Thanks guys! - it is so much more clearer now - especially with this: http://gstwins.com/gsboard/index.php?topic=49127.msg562620#msg562620
and your instructions above  - I just have to get down to doing it - will let you know how it goes, I have a feeling she is going to be tight....and at that point when nothing fits in the clearance area...how do you know which smaller shim size to get?
Title: Re: Valve Clearance
Post by: romulux on April 16, 2010, 10:27:46 AM
You have a couple options if a gauge doesn't fit in the gap.  If you can turn the shim bucket with your finger or a screwdriver or something, then the shim is not in contact with the cam lobe.  In other words, you still have at least some clearance.  This is good.  You can swap to the next smaller size, then, and you will almost certainly be in spec.

Otherwise, if you're really worried, see if you can get your dealer to lend you 4 small shims that are significantly smaller than the ones you currently have.  Take all 4 of your existing shims out, put the 4 small ones in, and measure the actual clearance.  Calculate the shim sizes you need and take the small shims back to your dealer and get the ones you need.
Title: Re: Valve Clearance
Post by: vorBH on April 16, 2010, 10:38:34 AM
Ah makes sense - I gota get under there - will update on the clearance of the valves, I am interested to know
Title: Re: Valve Clearance
Post by: Allen on April 19, 2010, 08:12:17 PM
Here was my case, I ran my bike til it stopped working about 19,000 miles, when I opened it up, the left exhaust had zero clearance and I could not freely rotate the bucket.  On the right exhaust, I could not fit the smallest feeler, but could rotate the bucket so one size down was perfect for that side.  I did two sizes smaller for the left exhaust and still could not rotate the bucket, then two more sizes down I was in spec.  The symptoms prior to this was stalling when comming to a light and a super long warm up time.  The bike runs great now.
Title: Re: Valve Clearance
Post by: vorBH on April 19, 2010, 08:15:42 PM
Thank you. This information is very useful.
I am wondering if oil consumption is also related to valve clearances?...no visible oil leaks around gaskets..
Title: Re: Valve Clearance
Post by: Markca on April 28, 2010, 06:50:40 AM
Quote from: Allen on April 16, 2010, 01:50:45 AM
First get everything off, also remove the spark plugs as it makes it easier for you to turn the engine.  As you turn the crankshaft with the 19mm, you will notice the camshafts rotating; the ends of the camshafts have a rectangular cut-out like a keyway, rotate the engine until these are facing each other, the left exhaust lobe should be facing directly down, and now you can measure the clearance on the right exhaust as well as the two intake clearances.  Now rotate the engine so the keyways are facing away from each other and measure the left exhaust.  If your bike was running poorly prior to this, you may have zero clearance on one or both exhaust valves, try to fit your slimmest feeler, if it doesn't fit try to rotate the bucket with your finger, if it rotates then it has at least some clearance. Good luck, hope it helps.
When I measured mine, if I followed the instruction as above, I could not fit the smallest feeler (0.034mm) in to both the intake valve.  However, if rotate the engine so that the lobe is pointing away from the bucket then I could fit even the 0.05mm feeler in.  Should I be worry about the valve clearance too tight?  My bike only has 4000 miles.  I would hate to open it up and do it all over again, specially replacing the bucket, hopefully I can delay that for next year you think it's not too serious :).
Title: Re: Valve Clearance
Post by: pandymai on April 28, 2010, 07:02:28 AM
Quote from: Markca on April 28, 2010, 06:50:40 AM
Quote from: Allen on April 16, 2010, 01:50:45 AM
First get everything off, also remove the spark plugs as it makes it easier for you to turn the engine.  As you turn the crankshaft with the 19mm, you will notice the camshafts rotating; the ends of the camshafts have a rectangular cut-out like a keyway, rotate the engine until these are facing each other, the left exhaust lobe should be facing directly down, and now you can measure the clearance on the right exhaust as well as the two intake clearances.  Now rotate the engine so the keyways are facing away from each other and measure the left exhaust.  If your bike was running poorly prior to this, you may have zero clearance on one or both exhaust valves, try to fit your slimmest feeler, if it doesn't fit try to rotate the bucket with your finger, if it rotates then it has at least some clearance. Good luck, hope it helps.
When I measured mine, if I followed the instruction as above, I could not fit the smallest feeler (0.034mm) in to both the intake valve.  However, if rotate the engine so that the lobe is pointing away from the bucket then I could fit even the 0.05mm feeler in.  Should I be worry about the valve clearance too tight?  My bike only has 4000 miles.  I would hate to open it up and do it all over again, specially replacing the bucket, hopefully I can delay that for next year you think it's not too serious :).


when checking valve clearances, you need to make sure the lobes on the cams are pointed away from the shims. if not, they will be pressing against the shims/buckets and you wont get anything under them.  when you could fit the .05mm in after you rotated the engine, that's probably where you should have checked the clearance for that cylinder. i could be wrong though, seeing as how im not quite sure where in the rotation of the cams you were actually gauging.
Title: Re: Valve Clearance
Post by: Markca on April 28, 2010, 07:13:42 AM
I hope you are right Pandymai.  Kerry video show that he measure the clearance the same way.  However, in the service manual book, it measure it like what Allen described in his post.
Title: Re: Valve Clearance
Post by: Paulcet on April 28, 2010, 07:18:16 AM
Quote from: pandymai on April 28, 2010, 07:02:28 AM
Quote from: Markca on April 28, 2010, 06:50:40 AM
when checking valve clearances, you need to make sure the lobes on the cams are pointed away from the shims. if not, they will be pressing against the shims/buckets and you wont get anything under them.  when you could fit the .05mm in after you rotated the engine, that's probably where you should have checked the clearance for that cylinder. i could be wrong though, seeing as how im not quite sure where in the rotation of the cams you were actually gauging.

Not much difference in the two methods, but there is a difference.  Here's the manual: Click (http://www.familyjones.org/paul/valve_adj.pdf)
Title: Re: Valve Clearance
Post by: pandymai on April 28, 2010, 08:55:00 AM
the way Kerry shows you how to do it in the video is visually by each cylinder. meaning: he rotates the cams until he see's the lobe face away from the valve/shim he wants to check. by doing this, he rotates to the position necessary for him before checking each valve.

In the manual, it shows you how to line up the cams in order to check 3 at once, then the last after a full rotation of the cams.  this works because of the placement and angle of the cam lobes. when looking at the cams, they wont all be 90 degrees away from their valve/shims, but the clearance will still be at the maximum allowing for the clearance to be checked.  both ways work. depends on personal preference.

either way, the important part is: the cam lobe has to be in a position that allows for the greatest distance between the shim and the cam. that's where you check the clearance.
i hope that helps.
Title: Re: Valve Clearance
Post by: Markca on April 28, 2010, 09:01:22 AM
Quote from: pandymai on April 28, 2010, 08:55:00 AM
the way Kerry shows you how to do it in the video is visually by each cylinder. meaning: he rotates the cams until he see's the lobe face away from the valve/shim he wants to check. by doing this, he rotates to the position necessary for him before checking each valve.

In the manual, it shows you how to line up the cams in order to check 3 at once, then the last after a full rotation of the cams.  this works because of the placement and angle of the cam lobes. when looking at the cams, they wont all be 90 degrees away from their valve/shims, but the clearance will still be at the maximum allowing for the clearance to be checked.  both ways work. depends on personal preference.

either way, the important part is: the cam lobe has to be in a position that allows for the greatest distance between the shim and the cam. that's where you check the clearance.
i hope that helps.
The problem is using the Manual method I could not get 2 of the valve clearance to pass the 0.034mm gap.  Should I be worry?
Title: Re: Valve Clearance
Post by: pandymai on April 28, 2010, 09:12:50 AM
Quote from: Markca on April 28, 2010, 09:01:22 AM
The problem is using the Manual method I could not get 2 of the valve clearance to pass the 0.034mm gap.  Should I be worry?

theoretically, manual method or kerrys method, either way should give you the same result. so if somehow you got different results, sadly but surely you should double check your work.  both ways are designed to look for one thing only - clearance between the cam lobe and valve shim.  both ways work.

if you couldnt fit your smallest gauge (seemingly .034mm) but the bucket would spin under the cam than you should probably pull the shim out, measure it, and go one size down. if anything, trial and error goes a long way, unless your bike is your primary source of transportation (as it is for me) than i'd say you should take any free time to get it right.

im no pro, but i'd like to say i understand what i do when i do it =P
Title: Re: Valve Clearance
Post by: Markca on April 28, 2010, 09:26:41 AM
Quote from: pandymai on April 28, 2010, 09:12:50 AM
Quote from: Markca on April 28, 2010, 09:01:22 AM
The problem is using the Manual method I could not get 2 of the valve clearance to pass the 0.034mm gap.  Should I be worry?

theoretically, manual method or kerrys method, either way should give you the same result. so if somehow you got different results, sadly but surely you should double check your work.  both ways are designed to look for one thing only - clearance between the cam lobe and valve shim.  both ways work.

if you couldnt fit your smallest gauge (seemingly .034mm) but the bucket would spin under the cam than you should probably pull the shim out, measure it, and go one size down. if anything, trial and error goes a long way, unless your bike is your primary source of transportation (as it is for me) than i'd say you should take any free time to get it right.

im no pro, but i'd like to say i understand what i do when i do it =P
They should give the same result, but if I can rotate and able to get the 0.05mm clearance, then that would mean that the maximum clearance is at least 0.05mm right?  So what I did wrong is unable to follow the manual, but as far as the clearance go, it should be OK, shouldn't it???
Title: Re: Valve Clearance
Post by: pandymai on April 28, 2010, 09:32:25 AM
everyone's feel is a little different, so it's hard to tell. but since youre pretty sure you got to within spec for each valve, than i see no reason to worry. :thumb:

glad to be of assistance.
Title: Re: Valve Clearance
Post by: gsJack on April 28, 2010, 09:35:57 AM
If you can turn the bucket with your finger tip with the cam lobe turned away from the shim your bike will run OK and probably do so for many more miles.  Nothing to panic about but if you want to get 100k miles from your engine without valve work you better run more exhaust valve clearance.  If you want to do it right you should check clearances with the cams set like the manual shows.  Using Kerry's method will give slightly different usually tighter values.

About 11 years ago with my first GS I let an exhaust valve go with minimum clearances for 20k miles and that valve needed frequent shim changes after that until it was down to a minimum 215 shim by 80k miles.  On my current 02 GS I've increase exhaust clearances and am now approaching 80k mile still running mid size shims and expect them to go 100k miles with little or no more shim changes.  Still, I didn't change my first shim until about 40k miles on the 97 and about 30k miles on my 02.  That's when I began increasing clearances on the exhausts on the 02.  Will be doing my 80k mile check next month on the 02 with about 79k miles on it now.

http://img.photobucket.com/albums/v443/jcp8832/valveclearances.jpg
Title: Re: Valve Clearance
Post by: Allen on April 29, 2010, 11:45:38 AM
Watch Kerry's video, thats how I learned it, but the book's way allows you to check both intakes and the right exhaust at the same time. In general the lobe needs to face away from the shim/bucket, then measure clearances.  What you worry about is when the lobe is facing away and the back end of the lobe is still touching the shim (ie. zero clearance).  Don't worry you are doing fine, as long as you have clearances the bike should run fine, you may have to readjust your idle or other things afterwards.