ok so i checked my valve clearence today and all of them are to tight. i couldnt any of my feeler gauges in, but the shim bucket still rotates freely. this link says to just go down 1 size if it rotates. http://www.bbburma.net/Documents/ValveAdjustmentVideo/GS500_Valve_Shim_Selection_Chart.gif
my left intake valve currently has 2.5mm shim
my right intake valve currently has 2.2mm shim
my left exhaust valve currently has 2.7mm
and my right exhaust valve has 2.2mm shim
so i need to order two 2.15mm shims, a 2.45mm shim, and a 2.65 shim right?
also next time i need to adjust the valve clearence where can i get a smaller shim than 2.15?
Quote from: tiptonmustang24 on May 19, 2009, 04:00:08 PM
ok so i checked my valve clearence today and all of them are to tight. i couldnt any of my feeler gauges in, but the shim bucket still rotates freely. this link says to just go down 1 size if it rotates. http://www.bbburma.net/Documents/ValveAdjustmentVideo/GS500_Valve_Shim_Selection_Chart.gif
my left intake valve currently has 2.5mm shim
my right intake valve currently has 2.2mm shim
my left exhaust valve currently has 2.7mm
and my right exhaust valve has 2.2mm shim
so i need to order two 2.15mm shims, a 2.45mm shim, and a 2.65 shim right?
also next time i need to adjust the valve clearence where can i get a smaller shim than 2.15?
Are you sure you had the right set of feeler gauges and measured the clearance correctly? How many miles are on the bike? It seems unusual to need intake shims, and you needing all four shims might actually be you needing to measure differently. Also, 2.15 is the minimum shim size. If you go below that, you might get lucky and be able to grind some of the valve stem off to get more clearance, but after that you're going to need a new valve and guide, assuming your seats are good, which is a major operation.
Yeah if all of them are off, double check that you did it correctly. I did it last weekend, and wasn't getting anything to fit until I made sure I was doing it correctly. Particularly, that you measure when the notches on the camshaft are facing each other, for 3 valves then when they're facing outward for the 4th. Have you seen this (http://gstwin.com/adjust_valves.htm) paying special attention to step 8? Also, is your feeler guage SAE or metric? If you're trying to fit a .03 inch blade in a .03 mm slot that could cause trouble? :)
you could probably have your shims ground down a bit further on a surface grinder if it comes to that. Check the hardness before and after, and re-establish the chamfer.
the bike only has 12000 miles.....the way i measured was i made the cam lobe face away from the valve fore each valve
Quote from: commuterdude on May 19, 2009, 05:33:04 PM
you could probably have your shims ground down a bit further on a surface grinder if it comes to that. Check the hardness before and after, and re-establish the chamfer.
I'd only grind the underside of the shim if these are like other shim in bucket adjustment shims I have seen (watercooled VW). I think the side the cam sees would need to be smoother than what a surface grinder would make. IMHO.
It's a good idea to grind just the bottom surface since the shims are surface hardened. If you grind off the cam's contact surface you'll be strangely enough be risking wearing both the cam and shim out because you're bringing the hardness of both wear surfaces closer to each other.
Heh, same advice different reason. My gut tells me that grinding down one size wouldn't go thru a surface hardened layer, but I don't know for sure.
That's a 93 GS with about 12k miles on it and you're down to almost minimum shim thickness? Must have had a valve grind job or head/engine swap or something like that. First recheck those valve clearances like PachmanP suggests above by aligning the cam notches and timing marks like the book says.
About 10 years and 145k GS miles ago I started doing my first valve check like you did by putting the cam lobe away from the shim and got tight readings. Did it over like the book says and got clearances within tolerance all around. My 97 GS didn't require an exhaust shim change until 39k miles and my current 02 GS got it's first exhaust shim change at 31k miles.
All of my original factory shims were between 2.58 and 2.65 mm and the intake valve shims didn't need changed in 80k on the 97 and 70k so far on the 02 GS.
http://img.photobucket.com/albums/v443/jcp8832/valveclearances.jpg
I wont grind nothing on a shim, you take off even a couple 1000's and bye bye o ... Besides you will leave such serious grooves and crap in it it will be unbelievable.
Cool.
Buddha.
Not on a surface grinder in a machine shop.
On the back side it should be fine.
Quote from: The Buddha on May 20, 2009, 08:49:47 AM
I wont grind nothing on a shim, you take off even a couple 1000's and bye bye o ... Besides you will leave such serious grooves and crap in it it will be unbelievable.
Cool.
Buddha.
Why grind down shims when they are relatively cheap? I had one shim ground down to 2.0mm when I had my 78 GS750, but that was just so I could get a reading on the clearance and figure out the right shim to buy.
Quote from: jp on May 20, 2009, 09:25:57 AM
Why grind down shims when they are relatively cheap? I had one shim ground down to 2.0mm when I had my 78 GS750, but that was just so I could get a reading on the clearance and figure out the right shim to buy.
To get one thinner than normally available.
I still think it would have too many rough spots. They need to micro polish it after maybe.
The final risk is, past certain thickness a shim that size when pushed down, sideways and what not with the cam, will buckle, or curl or crumple like if you put a spinning tire against a sheet of paper on the floor ... prolly OK till you get into the sum 2mm range.
Cool.
Buddha.
Quote from: intergalactic on May 20, 2009, 09:04:38 AM
Not on a surface grinder in a machine shop.
On the back side it should be fine.
Quote from: The Buddha on May 20, 2009, 08:49:47 AM
I wont grind nothing on a shim, you take off even a couple 1000's and bye bye o ... Besides you will leave such serious grooves and crap in it it will be unbelievable.
Cool.
Buddha.
well i took the gs apart again today, measured it the way pachman suggested, using this link
http://gstwin.com/adjust_valves.htm
my smallest guage is .04mm and i couldnt fit it in between the shim and cam on any of the valves. Am i still doing something wrong? why do i have such a small clearance at only 12k miles? maybe the odometer was unplugged for awhile from previous owner? Am i still doing something wrong? Is there a trick to getting the gauge to fit?
Quote from: The Buddha on May 20, 2009, 08:49:47 AM
I wont grind nothing on a shim, you take off even a couple 1000's and bye bye o ... Besides you will leave such serious grooves and crap in it it will be unbelievable.
Cool.
Buddha.
^Plus whatever credibility I've got here.
I agree with Buddha.
Oh yeah just to add sanding shims is standard practice in the rarefied world of Ducati.
Quote from: tiptonmustang24 on May 20, 2009, 02:53:57 PM
my smallest guage is .04mm and i couldnt fit it in between the shim and cam on any of the valves. Am i still doing something wrong? why do i have such a small clearance at only 12k miles? maybe the odometer was unplugged for awhile from previous owner? Am i still doing something wrong? Is there a trick to getting the gauge to fit?
Yeah I've been looking for a metric guage that goes to .03 mm, and they're none too common. If your buckets are still turning freely, you're not too bad off. If you have the patience, you could get a 2.15 mm shim, put it in, and measure the gap to get the correct new shim.
I didn't seem to need any tricks to get my guage in, and if you align the notches on the camshaft, you're doing it correctly. Your guage blades aren't corroded at all are they? My smallest had some corrosion and wouldn't fit, but the next size up would go in.
Quote from: PachmanP on May 20, 2009, 04:40:52 PM
Quote from: tiptonmustang24 on May 20, 2009, 02:53:57 PM
my smallest guage is .04mm and i couldnt fit it in between the shim and cam on any of the valves. Am i still doing something wrong? why do i have such a small clearance at only 12k miles? maybe the odometer was unplugged for awhile from previous owner? Am i still doing something wrong? Is there a trick to getting the gauge to fit?
Yeah I've been looking for a metric guage that goes to .03 mm, and they're none too common. If your buckets are still turning freely, you're not too bad off. If you have the patience, you could get a 2.15 mm shim, put it in, and measure the gap to get the correct new shim.
I didn't seem to need any tricks to get my guage in, and if you align the notches on the camshaft, you're doing it correctly. Your guage blades aren't corroded at all are they? My smallest had some corrosion and wouldn't fit, but the next size up would go in.
Here is where I got mine:
http://www.use-enco.com/CGI/INSRIT?PARTPG=INSRAR2&PMAKA=990-2365&PMPXNO=3011568
They have many sizes, I ordered one of each. The gauge is a foot long, which is overkill, but the .03 mm one is really easy to put dents and stuff in, so being able to cut some off when it gets to worn is probably a good thing... You could also cut one into a few pieces and share the cost with someone else if you felt like it....
hey I didn't mean to open a can of worms with the shim grinding. I'm guessing that is how they are finished to size from Suzuki....ground in a group and after a pass or two one is removed, miked, marked, then a pass or two and the next one pulled and checked. They may sample the hardness of a few from that batch and toss them....can't have hardness test marks on your shim after all. I'm not a metallurgist but my guess is they are hardened through and ground to size. Some steels may be hard enough as is? Interesting topic, maybe I'll take one to work and check it....during breaktime of course.
If you surface grind one you will know in a minute if it has curled or whathaveyou. I'm sure there is a reason that thicknesses stop at 2.15mm but I'd sure try a few thou off to get me another 4000 miles or so, if I am looking at pulling the head anyway.
Quote from: commuterdude on May 20, 2009, 05:22:12 PM
hey I didn't mean to open a can of worms with the shim grinding. I'm guessing that is how they are finished to size from Suzuki....ground in a group and after a pass or two one is removed, miked, marked, then a pass or two and the next one pulled and checked. They may sample the hardness of a few from that batch and toss them....can't have hardness test marks on your shim after all. I'm not a metallurgist but my guess is they are hardened through and ground to size. Some steels may be hard enough as is? Interesting topic, maybe I'll take one to work and check it....during breaktime of course.
If you surface grind one you will know in a minute if it has curled or whathaveyou. I'm sure there is a reason that thicknesses stop at 2.15mm but I'd sure try a few thou off to get me another 4000 miles or so, if I am looking at pulling the head anyway.
I'm willing to bet Suzuki grinds them before hardening them. It would be way easier that way...
Quote from: fred on May 20, 2009, 06:54:57 PM
I'm willing to bet Suzuki grinds them before hardening them. It would be way easier that way...
No, it wouldn't - because the hardening process would muck them up. Grinding has no problem with hardened steel, and things hardened, then ground, stay as ground. Things ground, then hardened, do not.
Quote from: DoD#i on May 20, 2009, 07:17:12 PM
Quote from: fred on May 20, 2009, 06:54:57 PM
I'm willing to bet Suzuki grinds them before hardening them. It would be way easier that way...
No, it wouldn't - because the hardening process would muck them up. Grinding has no problem with hardened steel, and things hardened, then ground, stay as ground. Things ground, then hardened, do not.
If you take micrometers to them, they aren't really that flat, enough so to make me think they worked them soft then hardened...
so how many miles do yall think are really on my gs? its in pretty good shape, but with me needing the smallest available shim already at 12000miles? doesnt seem right to me. what am i going to have to do once i need to adjust them again other than grind the shim?
would it be cheaper to just buy a used engine once my valve clearence needs adjusted again?
Quote from: tiptonmustang24 on May 22, 2009, 03:15:49 PM
would it be cheaper to just buy a used engine once my valve clearence needs adjusted again?
No, not even close. You can grind the end of the valve for very little money, and when that stops working, you can replace the valve and guide. Once you've gone through that valve and guide, you'll probably have to replace the head. After that, rinse and repeat. You should never replace the engine just because you've got a valve that's tight... You might destroy things by leaving it tight, but as long as you're on top of maintenance, you'll be fine...
Also, your valve might just be tight because the factory made that valve a bit on the long side and put it in a head that had a seat a bit on the deep side. They can't make them all the same all the time, so you might just have been unlucky and got a really bad combination... You could also have had some problem, like that cylinder was running super lean and hot for a while and fried the valve... What does the plug on that side look like?
hey fred, how much would a bike shop charge to grind the valve?
You could do it for very much ... free.
Just get in there with a dremel tool ... and make sure you get it nearly straight and flat.
If you pulled them out ... might as well do the whole head and I know one place that would do for 100 ... they did the head I sold to ry_guy and to lopee.
That will actually be so precise, you can put these parts all in they will check the clearances are doing the 3 angle etc etc and then grind it that exact amount.
I think though they harden after grinding. You can grind anything of any hardness ... yea, but they dont through harden them. Surface only.
Cool.
Buddha.
Dremeling off the end of the valve in the head is a bad joke.
Even if you could get the end of the valve square, where does all the grinding grit go.
Don't do this.
Quote from: The Buddha on May 22, 2009, 06:19:24 PM
You could do it for very much ... free.
Just get in there with a dremel tool ... and make sure you get it nearly straight and flat.
If you pulled them out ... might as well do the whole head and I know one place that would do for 100 ... they did the head I sold to ry_guy and to lopee.
That will actually be so precise, you can put these parts all in they will check the clearances are doing the 3 angle etc etc and then grind it that exact amount.
I think though they harden after grinding. You can grind anything of any hardness ... yea, but they dont through harden them. Surface only.
Cool.
Buddha.