Checking Valve Clearances

[john]

Hi all,

Following some study on how to do this I have come across 4 different methods from credible sources. On this forum there has been talk of methods for this too. Some methods I have come across are:

• Checking in firing position,
• Aligning cams by sight so they are perpendicular to cylinder head
• Using governer markings to align crankshaft
• and more...

What is the correct way to check the valve clearances on a Suzuki GS1000G? Can you please give a very brief description of the steps.

 

[BassCliff]

Greetings and Salutations!!

Greetings and Salutations!!

Hi Mr. john,

You'll find the correct procedure documented on my little website. Use the 8-valve procedure, not the 16-valve procedure.

Now let me dump a TON if information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

 

[john]

Hi BassCliff,

Thanks for the welcome. I have got the clearances sorted.

The method I ended up using was the Clymer Suzuki Manual method of rotating the cams by sight so each one is perpendicular to the cylinder head when it is being measured.

Thanks again,
John

 

[Steve]

The method I ended up using was the Clymer Suzuki Manual method of rotating the cams by sight so each one is perpendicular to the cylinder head when it is being measured.

Glad you think you have it "sorted", but that is NOT the correct way.

If you read the Clymer manual carefully, you will see that you start with Exhaust #1 (that's the one under your clutch hand), align that cam lobe so it is FORWARD and #2 Exhaust lobe is UP. While in that position AND WITHOUT ROTATING THE ENGINE, measure BOTH, #1 AND #2 exhaust valves. Rotate the crank 180 degrees, Intake #1 will be UP, Intake #2 will be BACK. While in that position AND WITHOUT ROTATING THE ENGINE, measure BOTH, #1 AND #2 intake valves. Continue another 180 degrees on the crank, measure #3 and #4 exhaust the same way, a final 180 degrees on the crank, and you can check #3 and #4 intakes.

Note that, once you have the cams set up for the first check, you only move the crank THREE TIMES before you are done checking.


The reason? If you look closely, you will see that in those positions, neither cam lobe on that side of that cam is pushing on a valve. That will keep the cam centered in the bearing for consistent readings. If an adjacent valve is being pushed down, the cam will be pushed a bit off-center (which is minimized when running, due to the pressurized oil film), giving you a false reading.

.

 

[Nessism]

Yes, Clymers is wrong...BUT it is a small omission on their part, not grand larceny. The clearances will be off a smig, but nothing that will cause undue risk to your engine.

Please use the Suzuki method next time you do the valves but I wouldn't worry for now.

 

[2BRacing]

Hi John

Yes, there is actually only 1 method of setting these valve clearances, and that is according to the method described in the official Suzuki workshop manual, as explained above by Steve and in BassCliff's "How To". However, as Nessism said, you are probably good to go as it is.

May I suggest that you make use of Steve's kind offer (see his signature)to obtain a copy of his spreadsheet for keeping all the information regarding shims handy in one reference. Knowing which shims are in there at the moment will make it easy to plan ahead and obtain correct shims for your next adjustment session.

 

[john]

If you read the Clymer manual carefully, you will see that you start with Exhaust #1 (that's the one under your clutch hand), align that cam lobe so it is FORWARD and #2 Exhaust lobe is UP. While in that position AND WITHOUT ROTATING THE ENGINE, measure BOTH, #1 AND #2 exhaust valves. Rotate the crank 180 degrees, Intake #1 will be UP, Intake #2 will be BACK. While in that position AND WITHOUT ROTATING THE ENGINE, measure BOTH, #1 AND #2 intake valves. Continue another 180 degrees on the crank, measure #3 and #4 exhaust the same way, a final 180 degrees on the crank, and you can check #3 and #4 intakes.

I have re-checked the valve clearances using this method and had to change 4 shims. Yes I can see this method will give much more consistent results. Thanks for the tip.

 

[Steve]

I have re-checked the valve clearances using this method and had to change 4 shims. Yes I can see this method will give much more consistent results. Thanks for the tip.

Not really a tip, it's the factory-specified method.

Did you happen to notice this tip? :-k

May I suggest that you make use of Steve's kind offer (see his signature)to obtain a copy of his spreadsheet for keeping all the information regarding shims handy in one reference. Knowing which shims are in there at the moment will make it easy to plan ahead and obtain correct shims for your next adjustment session.

.