Valve shim question

mustangGT90210 · February 25, 2013, 07:32:27 PM

Just put new shims on all my valve. All are in spec except the left exhaust. I followed baltimoreGS's video on youtube, and even after dropping from a 2.45 to a 2.40 shim on the left exhaust, I'm still getting less than .02mm clearance. Could my valve have been that far out that I need to drop even further to a 2.35 or 2.30? Also, when manually cranking the engine during all this, I could hear a little hissing sound coming from the left exhaust shim area, would that mean the valve is still hanging open?

Twisted · February 25, 2013, 07:34:39 PM

It will hiss if you haven't pulled the plugs when you turn the engine manually.

craigs449 · February 25, 2013, 07:38:10 PM

Just keep swapping thinner shims until you get the proper clearance. It is possible for them to be that far out of spec. You are confused, BTW, the valves sink further into the head giving no valve shim clearance,......if it were hanging open, you would have plenty of unwanted valve clearance....

mustangGT90210 · February 25, 2013, 07:41:18 PM

Thanks for the hissing answer

Quote from: craigs449 on February 25, 2013, 07:38:10 PM
Just keep swapping thinner shims until you get the proper clearance. It is possible for them to be that far out of spec. You are confused, BTW, the valves sink further into the head giving no valve shim clearance,......if it were hanging open, you would have plenty of unwanted valve clearance....

Well looks like it's time to order a 2.35 and a 2.30. Unless someone on here wants to swap me for some combo of the (2) 2.55s and (1) 2.45 I have

Twisted · February 25, 2013, 07:42:51 PM

Dealers will sometimes swap shims with you.

Bluesmudge · February 25, 2013, 07:44:57 PM

Crank the engine by hand a few times to make sure the shim is seated properly. Also make sure that your feeler gauges didn't stick together. When I check my valve clearances I usually get at least one reading that doesn't make sense. When that happens I turn the engine over and re-do the valve check. If its still too tight then you might have to go down one more shim size but that shouldn't be the case.

mustangGT90210 · February 25, 2013, 07:52:29 PM

Quote from: Twisted on February 25, 2013, 07:42:51 PM
Dealers will sometimes swap shims with you.

Mine doesn't

Already tried

Quote from: Bluesmudge on February 25, 2013, 07:44:57 PM
Crank the engine by hand a few times to make sure the shim is seated properly. Also make sure that your feeler gauges didn't stick together. When I check my valve clearances I usually get at least one reading that doesn't make sense. When that happens I turn the engine over and re-do the valve check. If its still too tight then you might have to go down one more shim size but that shouldn't be the case.

I cranked it over multiple times thinking that was the case. Pulled the shim, put it back in, re-checked, cranked more, rechecked, double checked the how to, etc. I really think it still doesn't have any clearance

gsJack · February 25, 2013, 08:18:47 PM

After you have run a GS500 exhaust valve at the minimum Suzuki clearance spec of .001" (.03mm) for a long time the valve will begin to recede into the seat at a much more rapid rate. I changed shims on my 97 GS two sizes at a time repeatedly on one exhaust valve until it was down to a minuimum 215 shim before 80k miles.

When an exhaust valve started the same progression at a little over 30k miles on my 02 GS I bumped the clearance up to my new .003-.005" (.08-.13mm) setting and it then went another 40k+ miles before it needed another shim change. A loose exhaust valve is a happy exhaust valve!

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

mustangGT90210 · February 25, 2013, 08:20:47 PM

Thanks jack! I just want to get it back in spec first, and then run it loose. I'm starting to get scared I may have to pull a head if it's really bad

Kms254 · February 25, 2013, 09:38:41 PM

Ok after another try I think i got numbers
IL 0.07mm
IR 0.08mm
ER 0.08mm
EL 0.02mm

I am pretty sure the valve cover has never been off this motor, and it has 13K miles on it. I am kinda wondering about EL if my measurement is off since the other 3 are soo close... I just kept going up in feelers until it would not go between the shim and the cam. The 0.02mm feeler gauge barely fit the EL although the feeler gauge was so thin that could have contributed to it being hard to get in.

Does any one have any thoughts? I think I should just order a 0.05mm thinner shim to make it 0.07mm clearance for EL.

Twisted · February 26, 2013, 02:16:39 AM

Quote from: Kms254 on February 25, 2013, 09:38:41 PM
Ok after another try I think i got numbers
IL 0.07mm
IR 0.08mm
EL 0.08mm
EL 0.02mm

I am pretty sure the valve cover has never been off this motor, and it has 13K miles on it. I am kinda wondering about EL if my measurement is off since the other 3 are soo close... I just kept going up in feelers until it would not go between the shim and the cam. The 0.02mm feeler gauge barely fit the EL although the feeler gauge was so thin that could have contributed to it being hard to get in.

Does any one have any thoughts? I think I should just order a 0.05mm thinner shim to make it 0.07mm clearance for EL.

BTW you have 2 EL measurements there. Did you measure EL correctly as it is the one you have to have the notches on the cams facing away from each other to measure. If your measurement is correct you could go 0.10mm thinner and still be in spec.

wayne242 · February 26, 2013, 03:23:43 AM

don't mean to jump in with a question in your topic mustang, but don't want to make a new one for a related question.

What's a ballpark price range to have valve shims check and if needed corrected in a good shop? I like to have mine checked/done be for riding starts mid march/april.

Twisted · February 26, 2013, 03:29:49 AM

Quote from: wayne242 on February 26, 2013, 03:23:43 AM
don't mean to jump in with a question in your topic mustang, but don't want to make a new one for a related question.

What's a ballpark price range to have valve shims check and if needed corrected in a good shop? I like to have mine checked/done be for riding starts mid march/april.

It is really easy to yourself. Hardest part is removing the tank and valve cover and thats not hard. There are numerous walkthrough vids to - http://www.youtube.com/watch?v=j4vRm9xADa8

Kms254 · February 26, 2013, 08:21:15 AM

Quote from: Twisted on February 26, 2013, 02:16:39 AM
BTW you have 2 EL measurements there. Did you measure EL correctly as it is the one you have to have the notches on the cams facing away from each other to measure. If your measurement is correct you could go 0.10mm thinner and still be in spec.

Your right I updated my post. Think it would be better to go 0.10 thinner and have it "extra" loose? Vs 0.05 and have having them match? Or maybe loosen up the ER 0.05mm and the EL .10mm.

gsJack · February 26, 2013, 08:36:24 AM

Quote from: Kms254 on February 26, 2013, 08:21:15 AM
Think it would be better to go 0.10 thinner and have it "extra" loose?

Good enough.

Quote from: Kms254 on February 26, 2013, 08:21:15 AM
Or maybe loosen up the ER 0.05mm and the EL .10mm.

Even better.

mustangGT90210 · March 02, 2013, 03:02:51 PM

Valves are finally in spec! Haven't yet had a chance to ride though

Left exhaust valve was really out of spec. Had a 2.45 shim before, had to drop all the way to a 2.30 to get a .08mm clearance. Now all should be well

Twisted · March 02, 2013, 04:23:13 PM

That valve must have been really tight. You could have gone to a 225 and still been in spec. What did you go from a 245 to a 230? I would say it will start much better now.

rharding91 · March 02, 2013, 09:05:37 PM

I am like afraid to touch my valves, I need to do them its just that I am not sure what the specs exactly are? What are the clearances your looking for?

Twisted · March 03, 2013, 01:54:05 AM

Watch one of BaltimoreGS's videos in the video tutorial thread. Intake valves .03 - .08 and exhaust are the same but you can run them as loose as .13. As GSJack would say a loose exhaust valve is a happy valve.

mustangGT90210 · March 03, 2013, 01:15:47 PM

Quote from: Twisted on March 02, 2013, 04:23:13 PM
That valve must have been really tight. You could have gone to a 225 and still been in spec. What did you go from a 245 to a 230? I would say it will start much better now.

Yeah it was crazy tight to say the least. And yes, dropped from a 2.45 down to a 2.30. I've only started it once since I put the shim in... started up the same, but I noticed a major increase in power from before the valves to now.

Major to the point I almost pulled the front wheel off the ground without trying to!

It's never been even close to that before

News:

Valve shim question