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Main Area => General GS500 Discussion => Topic started by: Yoda on June 08, 2015, 06:39:44 AM

Title: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 08, 2015, 06:39:44 AM
A couple of the valves on my 2000 GS500E are out of spec and at least 1 of the shims is already down to a 200. So what does one do when they get to the smallest shim? I assume there is some sort of painfully complicated job to be done that "resets" the valve clearances? (replace the valves?)  :dunno_black:
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: bombsquad83 on June 08, 2015, 07:13:40 AM
How many miles are on the engine?  Easiest fix would probably be to get a replacement engine or head.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: bmf on June 08, 2015, 07:51:57 AM
Valves do stretch over time, all you need to do is to grind a few thou off the end of the valve. Probably a good time to re cut or reseat  the valves at the same time.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 08, 2015, 08:21:52 AM
@bombsquad83: Replace the engine?? I could probably buy another bike for the cost of doing that.

@bmf: Is that something that I should try doing myself? Or something that I should talk to my local bike shop about?
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: bmf on June 08, 2015, 11:48:23 AM
Any machine shop can do it you want a smooth job at the right angle.,  but head will have to come off.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Bluesmudge on June 08, 2015, 11:56:28 AM
You can usually find a complete and functional head for around $200. It might be easier to replace than repair.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: bmf on June 08, 2015, 12:19:13 PM
I bought new one to fix the buggered exhaust bolts on my old but being an anal retentive I then fixed the old as a spare. The new head tells me it is much happier in Montreal than it was in Texas ;-)
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: MeeLee on June 08, 2015, 07:14:50 PM
No new engine is necessary.
Some dealers can install new shims.
If not, they can install new cylinder heads.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: bombsquad83 on June 12, 2015, 10:02:03 AM
You didn't answer how many miles are on the engine.  If there are over 100,000 miles on it, then I would replace it due to wear on components like timing chains, piston rings, bearings, etc. that will catch up with you sooner than later.  If there are more like 60,000 on it, then replacing the head as bluesmudge mentioned would be the most cost effective.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: W201028 on June 12, 2015, 02:09:36 PM
You can always have the shims ground down by a local machinist, any auto place or production shop can do it.This is the easiest, cheapest thing to do.
I would say you could run those shims down at least until they no longer sit higher than the lip on the bucket, maybe further since the point of contact with the cam is so small.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 20, 2015, 01:12:32 PM
Thanks for the advice so far. Here is a little more information (including how many miles are on it):

It is a 2000 GS500E. It's my first bike (had it about a year now) and I have learned more and more that the previous owner was an idiot.

The bike only has about 27,000 miles on it (I know... too early to be having this issue, right?). It ran great for quite some time after I bought it and then started showing symptoms of needing a valve adjustment.

At the moment it is in my garage and my goal is to get the valves back in spec, clean the carbs, and do an oil change before getting back on the road with it.

I have a very limited budget to get it into better shape (and it has to happen now while I'm on summer break because I use it every day during the semester to get to college).

I am reasonably capable and more than willing to learn, so I hope to mostly put in hours rather than dollars here.  :technical:
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: gsJack on June 20, 2015, 03:10:10 PM
I would suspect that 27k milage figure.  Did my first shim change on my 97 bought new at about 40k miles and on my 02 at about 30k miles.  My 97 was down to a 215 minimum shim at 80k miles and I was pondering what to do, considering grinding off the valve stem w/o dissasembly or grinding down a shim, and before I did the bike was totalled and replaced by the 02.  Not a good solution.   :icon_lol:
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 20, 2015, 03:26:49 PM
I had considered that the 27K was not accurate, but now reading your post I am fairly sure it isn't.

So I guess at this point my only questions is: what can/should I do to get the valve clearances back in spec?
Grind down valve stems?
Grind down valve shims?
etc?

Any advice would be greatly appreciated.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: sledge on June 21, 2015, 06:12:21 AM
If you have run out of adjustment your valve seats are worn to their service limit.

2 options......

A) You take it to a shop, they replace the valve seats and recut the faces.
B) You find and fit a used head

Grinding valves and shims (if you think that is a good idea)  alleviates the problem but doesn't solve it. Think about it,......... your gap might be ok now but the seats are still worn!  :dunno_black:

Suzuki quote service limits for a reason. I cant say what will happen if you go beyond them but  Suzuki know far more than me and if they are suggesting its a bad idea......that's good enough for me  :thumb:
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: gsJack on June 21, 2015, 03:45:06 PM
If my 97 with the 215 shim hadn't been wrecked and replaced I would have gone to smaller shims most likely and got another 10-20k miles out of it.  The 215 is the smallest Suzuki made for the GSs but there are aftermarket ones down to 200.  With the broken K&L shims some have had damaging their engines I'm glad I didn't, best to use Suzuki shims only and grind them down.

No idea where you are at with your engine that probably has more miles than indicated or at least the head does.  A compression check both cold and hot would give some idea and be a good place to start.  Can you turn the buckets with your finger with  the cam lobe turned away?

Title: Re: What do you do when you can no longer do valve adjustments?
Post by: W201028 on June 21, 2015, 06:59:19 PM
Im really trying not to sound like an ahole, please keep that in mind. After re-reading this thread, your original post is pretty vague. Exactly how many valves are out of spec? Exhaust only? Also, you said at least one is down to a 200, that tells me you either measured one or could read the etching on it. Jack says 215 minimum for factory parts, so you either have aftermarket, or previously ground shims.
If the only problem is exhaust, the seat wear was most likely caused by a lean condition for a long period of time. If you want to go budget, have the shims ground again (if <200 clears the bucket, or you like to gamble), then clean the carbs or richen up the mixture if the bike is modified. You might get a lot more life out of it before the seats need redone, or replacement of the head.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: gsJack on June 21, 2015, 09:10:14 PM
Quote from: W201028 on June 21, 2015, 06:59:19 PM......................If the only problem is exhaust, the seat wear was most likely caused by a lean condition for a long period of time................

I've always attributed the receeding of the exhaust valves into the seats on the GSs to be due to the factory setting of .001-.003" (.03-.08mm) being too tight for exhaust valves, not enough cooling seat time.  One exhaust valve running at .002-.003" all the way required only one shim change and the other running at .001" a good deal of the time required repeated shim changes and was down to a min 215 shim at 80k miles on my 97 GS.

When the 02 GS started the same pattern at about 30k miles I increased my exhaust valve clearances to .003-.005" and after a couple changes they went 40-50k miles between shim changes on their way to 100k miles.

http://img.photobucket.com/albums/v443/jcp8832/GSvalvelogs_zps7kdr1yyh.jpg

The carbs remained untouched on both bikes for their entire lives.  Factory jets and settings all the way.

Title: Re: What do you do when you can no longer do valve adjustments?
Post by: W201028 on June 22, 2015, 02:21:53 PM
Wow jack, that log is excellent. It certainly looks like you logged more miles with a 3 or 4 thou gap between shim changes on the 02 than the 97 with factory tolerance. I assumed that suzuki set the tolerance so tight in an effort to gain all the power they could at higher rpm. Did you ever feel that the 02 was slightly down on power near the top after running 3-4?
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 22, 2015, 04:52:37 PM
Sorry for being so vague in my OP.

3 of the valve clearances are out of spec (all low)

Current shim sizes:
L Exhaust: 240
R Exhaust: 200 (Etched 200, so must be after market)
L Intake: 265
R Intake: Don't remember, but this one is in-spec

I don't have the valve cover off right now, I will try to get into it tomorrow if I have time. I don't believe I could turn the buckets (except on the valve that is in-spec).

Thanks again for all the help so far.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: W201028 on June 22, 2015, 05:44:46 PM
Tough call there, if you find you cant turn the buckets, theres a good chance you have negative lash, meaning the valve is not closing the whole way. This wears valves and seats, especially exhaust side. I had one of my exhaust like this at about 16k, it was about .001" open if I remember. I ground the shims and took a chance, hoping it would run good without replacing valves and seats. Been about 6k miles since then, runs nice but definitely lacking some high rpm power. Next time the valves get tight, it will be reseat time for me.
My advice is consider the options and your funds; grinding shims or valve stems will get you back into running order cheapest, but its more of a band aid. If the 200 shim doesnt sit higher than the top lips of the bucket, I dont know If I would grind it. Best choice there might be to take some off the stem and go up to a bigger, hopefully suzuki shim.
Im not sure the cost of new or reground valve seats, might be cheaper to get a known good head. There is always the option of grinding the seats yourself, but if you dont have much metal working experience this might not be the best choice. You could always check the valve seating area with dykem, find out if they did indeed burn to the point that they will not seal with the seats. If so, then try to lap them in a bit with some valve grinding compound, and see if you can get them all to seal decently. They wont have the "proper" angles for smoothest flow and seal, but backyard mechanics (like myself) have been building motors like this for years.
I just went through this with my old v8 ford, as I didnt want to put any more money into it than absolutely necessary. Runs great right now, but I dont drive it much or rely on it to get to work.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: gsJack on June 24, 2015, 03:12:39 PM
Was thinking about this today so went out to the barn to get a bucket and down to the basement to get shims to look at, my stuff is all over since last years move.   :icon_lol:  Smallest shim I had was a 230 so got pictures of bucket with and without shims.  There is a nice groove around the bottom of the shim c'bore in the bucket so shims ground flat would not need a chamfer or radius with ground side down.  The 230 shim sticks up about .012" above the bucket so it figures a 200 shim would be flush with bucket top.

If my 97 hadn't been totalled I would have gone down to a 200 shim for a fix before grinding the valve stem.  If it was already down to a 200 like Yoda is on one exhaust valve think I would have gone ahead with grinding the valve stem right off.   Think I'd call it quits at 200 on how far I'd go.  :dunno_black:  I was thinking of grinding it in place without pulling the head, if it didn't work out could then pull head and lap in new exhaust valves.

[attachment deleted by admin]
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 24, 2015, 04:55:30 PM
I think grinding a 200 shim is too much of a gamble for me, so that option is off the table.

I'm still considering grinding the stems, but I've got an opportunity to get my hands on a used head this weekend. Depending on the condition of that head my problem *might* be solved. (fingers crossed).

Hopefully I can simply swap out the head and then spend some time repairing the old one after the bike is running.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: W201028 on June 25, 2015, 03:54:39 PM
Cool deal jack, thanks for looking into that. While we might in theory be able to grind it down below the bucket, and still have the cam clear the lips, I dont think I would risk it either. Once it gets too thin, one could imagine the shim deforming under high rpm impact.
Yoda, you might be on the right track getting a spare head. Its alot easier to do a good job on a motor when you arent in a rush to get it together and go ride! Let us know how it looks, and dont be afraid to bring a straight edge and feeler guages to check the head for flatness. Even if its in spec, you can tell the seller its not and you would need to have it resurfaced, but you would be happy to give them half the asking price  ;)
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 28, 2015, 06:31:09 AM
The new head didn't cost me anything, drnickriviera sold his GS and was getting rid of spare parts. He said the guy that he got the head from said that it was off a running engine. Anything in particular I should check before I try putting it in my bike?

All but one of the buckets can be rotated by hand, I need to figure out why the last one is stuck (I assumed they only stuck when pressing too tightly on the cam).
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: The Buddha on June 28, 2015, 06:55:41 AM
I've been thinking about this. I'm pretty sure we could get a machinist to make 200-300 shims if we ordered 5-10 of each size. They should be speced to the old hardness and have numbers written on em, but otherwise its not that big a deal.
If someone has contacts - try em, I will see if I can find a couple I know around here.
Cool.
Buddha.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 28, 2015, 02:15:07 PM
One of the buckets in the new head was stuck. Took a bit of time + WD-40 to get it out. Not really sure why it was stuck yet.   :dunno_black:

I checked all the shim sizes, two of them where marked 265 and the the etching was gone on the last two so I measured with a micrometer (265 and 270). One of them doesn't look like a stock suzuki shim (missing the little bevel), but I think I have another 265 around here somewhere that is stock, so no big deal.

3 of the valves look good but the left exhaust valve looks a bit burnt. Gotta take my current head off and see what mine look like.

If I have a good exhaust valve in my old head would be be completely idiotic to just swap it with the burnt valve in the new head? (obviously it would have to be ground to to seal in the new head... but I can do that with valve grinding compound and a power drill  :thumb:)
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: W201028 on June 28, 2015, 02:17:56 PM
Probably could, we would need to know the specific grade of steel too. I know from experience these are not very magnetic, but I would be guessing at the metallurgy. My shop wouldnt take on a small job like that, but Ill ask around to see if any of the older guys know what type to use. Theres on old man in the shop that made his own two stroke motor, and I mean everything. He has some con rods and pistons he made in his toolbox!

Edit; looks like we posted at the same time. As long as the valve is in good shape and straight, I see no reason you cant swap them if needed.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 28, 2015, 02:57:10 PM
I gotta check the condition of my valves first, but I'm definitely leaning towards that option.

I've never had any trouble finding shims (last time I needed some I just talked to one of the guys out in the shop at my local dealer, he gave me 4 shims for like $9).

If y'all really want to get new shims made I'll ask around. I've got some contacts through work that might do it (or at least know who would).

Anyone know what these shims are made of and what hardness they are?
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: The Buddha on June 28, 2015, 07:31:29 PM
Quote from: W201028 on June 28, 2015, 02:17:56 PM
Theres on old man in the shop that made his own two stroke motor, and I mean everything. He has some con rods and pistons he made in his toolbox!



Old man = the best machinist. LOL. My favorite guy (made the case covers, braces, and kat stems - died a few yrs ago) Wasn't ever able to find another.

Cool.
Buddha.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on June 30, 2015, 09:33:46 AM
Tried to get my cylinder head off last night but it's pulling the cylinder up with it (can't get both out of the frame at the same time, so that's a problem). I can't get the dang thing un-stuck  :technical: and it's driving me nuts. I've undone the nuts on the 8 studs and the little upside down bolt in the front that holds the two together. Any ideas what else could be holding the two together?

I'm thinking about re-doing my piston rings and re-honing the cylinders while I'm in there... but this all hinges on being able to get it out of the bike in the first place.  :mad:
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: cWj on July 02, 2015, 09:44:01 AM


:dunno_white:

Title: Re: What do you do when you can no longer do valve adjustments?
Post by: W201028 on July 02, 2015, 09:52:54 PM
Be careful; do NOT pry on the fins, this can result in damage that will affect cooling. Use a rubber mallet and a piece of wood to tap upwards on the head, while holding the block down. Get help from a friend if needed. Its not worth the damage to pry on a fin or gasket surface.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: noworries on July 03, 2015, 05:59:54 AM
Good old fashioned  Aussie engineering....the A$ is down in the cellar.......overseas post at $33 for 500g.....give 'em a try....

http://www.precisionshims.com.au
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: The Buddha on July 03, 2015, 07:02:09 AM
Quote from: noworries on July 03, 2015, 05:59:54 AM
Good old fashioned  Aussie engineering....the A$ is down in the cellar.......overseas post at $33 for 500g.....give 'em a try....

http://www.precisionshims.com.au

They stock 29.5 mm dia shims in .05mm increments.

I submitted an order for - 2mm - 3 mm in .02 mm - which may be overkill. But its 50 sizes and I asked for 10 of each.
I dunno if its wise to exceed the 2.15-2.85 mm range Suzuki has ?? Atleast, I could drop those outsized ones and go to .05mm and maybe same me some $$$.

Cool.
Buddha.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: Yoda on July 03, 2015, 01:02:53 PM
Finally got the head off. I went with a mallet + a block of wood + a little help from my brother-in-law. just need another pair of hands to hold the cylinder down while I smacked it.

The valves in my old head look very burnt so I wont be scavenging any of those for the new head.

I'm trying to decide if I want to replace the valve seals and re-seat them or if I just want to leave them alone. I filled the new head with WD-40 to see if it holds or leaks out.

Before I put it all back together I think I'm gonna replace my Piston rings and re-hone the cylinders. Anything else I should do while it's opened up?
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: The Buddha on July 03, 2015, 07:42:08 PM
Here is the reply from the Australian site posted by noworries -

I have these shims, looks like there is 21 thicknesses x 10 each so that's 210 shims, that's a lot of shims.

For this many I'll do a good price for you at $6.50 each plus postage as below.


So - 
AU $6.50 - X 210 - maybe I was over eager to ask for 10 each in .02 mm increments. Over AUD 1400 - what's that is real $$$ ??? Someone ???

Factory sizes are .05mm apart and 2.15 to 2.85.

Anyway, It looks like there is an option. We now just bite the bullet and do a group buy ...

Cool.
Buddha.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: The Buddha on July 03, 2015, 07:53:34 PM
I've been thinking - 210 shims are a drop in the bucket compared to our yearly need for shims as a group.
However I don't have $1400 lying around.

I'd be in for 2-3 of all sizes 250-280 ... about 30-35 shims.
Maybe the vast majority of shims in our bikes are 250-280 (assumption - cos every gs I ever opened up had nothing 250-280) ...

Maybe I should collect up a list ...

Anyway Australian $$$ is running 75c to USD, shipping is $33 ...

I'll open up a thread but I'll take orders ... look in your bikes and order 1-2 sizes out from the thinnest and thickest ... 1-2 each ...

So then I'll round and total ...

Now would an aussie take the lead on this ??? make sure their shims wont break etc and work with them and have it made right ???

Cool.
Buddha,
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: The Buddha on July 05, 2015, 05:53:13 AM
They added this -

Yes the Chinese shims are just rubbish from the start, ie wrong material , not even close, wrong hardness not even close, but they are cheap.

The more people can know that Chinese ones are just rubbish the better, on the other hand some people just don't learn. !

I'll stand by for your order.

Thanks.
Srinath.
Title: Re: What do you do when you can no longer do valve adjustments?
Post by: noworries on July 16, 2015, 02:32:53 AM
More nice GS500 bits from an Oz supplier......dollar's down and some of this kit could get the GS's mass down...

http://www.probolt-australia.com/vaf/product/list/?Manufacturer=83&Model=1571&Type=8&Year=1574&category=%3F&p=1&x=25&y=12