Valve Shim Experts Help!

[djscottymiami]

Alright, I decided to plunge into my 80 GS850 today since I had the day off and check the valves.

PITA #1 : Getting the valve cover off. I had to go buy a rubber mallet and it still barely came off. It was on there GOOD.

PITA #2: Valve Shim Tool. Man can that thing spray oil

PITA #3: Shims that were sliding around


Now to my problem.. I've got 5 valves that I couldn't get a 1/1000 feeler gauge under.



#1 Exhaust: 0.04mm clearance, 2.55 shim
#1 Intake: 0.04mm clearance, 2.60X shim

#2 Exhaust: <0.03mm clearance 2.60 shim
#2 Intake: <0.03mm clearance 2.60X shim

#3 Exhaust: <0.03mm clearance 2.60 shim
#3 Intake: <0.03mm clearance 2.70 shim

#4 Exhaust: 0.04mm clearance 2.60X shim
#4 Intake: <0.03mm clearance 2.65X shim



Can someone help me with what sizes of shims I need to try and find?

I'm also having one hell of a time getting the old gasket off. Right now it's been over an hour and a half and i've only got half the old gasket scraped off... its only 10degrees celcius outside right now too so its pretty cold in the garage.

Would these clearances being out maybe explain why I'm only getting 29mpg with the bike?


Thanks in advance for the help!

[Steve]

Please allow me to insert a shameless plug here.

Toss an e-mail in my direction (click on my name for the address) and I will send you a copy of my valve adjust spreadsheet. It will help you determine what shims you need and will keep track of your shims for future adjustments.

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[psyguy]

ask "steve" for a spreadsheet that calculates shim sizes for you

that'd be the easiest if you have probs working it out

yup, poor valve clearances contribute to excessive fuel consumption

use gasket remover can spray to disolve th old gasket goo

[psyguy]

damn steve you re fast!

[djscottymiami]

Please allow me to insert a shameless plug here.

Toss an e-mail in my direction (click on my name for the address) and I will send you a copy of my valve adjust spreadsheet. It will help you determine what shims you need and will keep track of your shims for future adjustments.

.

I've got your spreadsheet already I just couldn't find it actually until 2 seconds ago.


My only problem is that if the 0.03mm feeler gauge doesn't fit, should I just enter it as 0.02 or 0.01mm in the equation sheet?

[dwvoss]

My only problem is that if the 0.03mm feeler gauge doesn't fit, should I just enter it as 0.02 or 0.01mm in the equation sheet?

If you have a spare shim, you might try replacing your 2.55 with a spare, and then moving the 2.55 into each of the other positions that are too tight to see if you can get a gap that is too big. Then you can easily determine the shim size you actually need.

I picked up a 2.15 shim (smallest available) to use for this purpose when I encountered a clearance that was way too tight. It was a good idea, but unfortunately the outcome was that even by 2.15 didn't provide enough clearance -- diagnosis - costly valve job to consider . But that's another thread.

[Steve]

I've got your spreadsheet already I just couldn't find it actually until 2 seconds ago.


My only problem is that if the 0.03mm feeler gauge doesn't fit, should I just enter it as 0.02 or 0.01mm in the equation sheet?

If you are using metric feelers, enter anything you want that is less than .03. Anything less than .03 will trigger the alert to let you know that it's too tight.

Before you change out the shims, try something. Go to one of your 'tight' valves, point the cam lobe away from the valve and see if you can spin the shim and/or bucket. If you can, you know there is some clearance, so one shim size should be OK. If it's too tight to spin, you might want to go two sizes.

I see that you have some X shims, you might want to take those into account, too. My instructions do not address how to handle X shims. What I have done for my bikes is to add .02 to the measurement when I log it. For example, your 2.60x shims would be entered as 2.62 and your 2.65x shims would be entered as 2.67. It will suggest a shim that is .05 different, so the suggestion for your 2.60x (2.62) would be 2.57. You will have to interpret this as a 2.55x if you want to go a full size. You might also try a 2.60 if you have one available. Either way, be sure to record the shim that you leave in there and also enter the final clearance measurement. These values will be carried to the next page for your next adventure in shim swapping.

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[Steve]

damn steve you re fast!

Whaddya mean? There was a gap of four whole minutes between his post and mine.




By the way, most people think I'm only half-fast. (Careful how you say that.)


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[djscottymiami]

Thanks... ill try that out after supper.

Looks like all i'll have time for tonight is to scrape the rest of the gasket off and put the cover back on just for tonight. Tomorrow i'll put the new gasket on and clean it all up and put it back together... i'm just too exhausted to keep going... plus the girlfriend wants some attention too lol

[Steve]

... plus the girlfriend wants some attention too lol

Suggest to her that if she comes out and helps you with recording the numbers, you will get done quicker and have more time for her.

.

[Joe C]

I see you have a couple exhaust valves at .04 mm. When I stopped in at CRC2 in Indy several weeks ago to get my shims, they said to stay .03-.08 mm on the intakes, but to use .05-.10 mm on the exhaust. It might not be a bad idea to go ahead and open up the .04 mm exhausts while you're in there.

[psyguy]

Suggest to her that if she comes out and helps you with recording the numbers, you will get done quicker and have more time for her.

.

that'd be a super-brave move... but put your helmet on before uttering those words

[BassCliff]

Hi Mr. djscottymiami,

It takes a little practice with the tappet tool. When it slips you get splattered.

In your case, basically what I would do is go down a size on every shim (-0.05). You don't have to buy 8 shims. You can put the 2.65 where the 2.70 is now. Then put the 2.55 where the 2.60 is now, etc. You'll still need to buy a 2.50 (to replace the 2.55) and about 4 of the 2.55s to replace the remaining 2.60s.

I've run my intakes at .09 with no problems. I've run my exhausts at .10 with no problems. I try to "fine tune" my clearances all to .08, but sometimes you just can't. I'd rather run a little too loose than a little too tight. Keep us informed.


Thank you for your indulgence,

BassCliff

[djscottymiami]

Suggest to her that if she comes out and helps you with recording the numbers, you will get done quicker and have more time for her.

.

Ya see the funny thing is I asked her that when i started and i wondered why she gave me such a dirty look

Side note, when I was checking the tight ones, i do remember being able to move the bucket around to get the notch where I needed it. So there's gotta be some clearance in there.

I've got the valve cover just resting on top of the head for tonight. I'll finish it all up tomorrow.

[GS750]

Ya see the funny thing is I asked her that when i started and i wondered why she gave me such a dirty look

Side note, when I was checking the tight ones, i do remember being able to move the bucket around to get the notch where I needed it. So there's gotta be some clearance in there.

I've got the valve cover just resting on top of the head for tonight. I'll finish it all up tomorrow.

I dont have to worry about that with my missus, she loves to get in and help me with the bike, and kinows it leaves more time for me to spend with her!

I just rebuilt my top end and managed to score a beaut bargain in the way of a genuine suzi shim set, brand new and only paid Au$200 for the wad of 130 shims.

I went about reshimming my whole setup and allowed .08-.14 clearances to allow for settling in since I had the valves and seats re-faced and had to include 2 new valves.

It has only done 300Km now and will be re-checked at 500Km to ensure that the clearances are still good.

I would much rather allow more than have them tight, and lets face it, its only .05mm so its certainly less likely to burn a valve and cause critical injury if you have the clearances upto .15mm.