Valve Clearence - advice please

[fatnfast]

I am about to adjust the valves on my 77 GS750 for the first time.

The Clymer states that the cam lobe points directly upwards to check each valve clearence. i.e turn the engine over for each of the 8 valves until the cam lope is pointing up, take the reading, adjust the shim size as required.

My old Suzuki manual states the the lobe can be pointing forward or upright.

Does it matter which method I use?

Thanks in advance.

[Nessism]

The Suzuki method places two adjacent valves on the cam base circle, unlike the Clymer method which allows the adjacent valve to press up on the cam and skew it within the journal clearance. I don't think it makes a whole lot of difference but I recommend the Suzuki method since chances are the clearance will read as lower using this method, and avoiding tight valves is the goal of valve adjustment on these bikes.

[fatnfast]

Many thanks for the quick reply . I will run with Suzukis method.

[fatnfast]

Well, its a good job I did this. Every clearance bar one has closed up to 0.03 or less (my smallest feeler guage is 0.03mm). This is on a bike that starts and runs very well. I have managed to swap some shims about so only need to order 4 replacements (not cheap, but cheaper than sorting out a burnt valve!).
If you have a very quiet valve train (like mine) and havent done the clearance/shims recently, nows the time!

[Steve]

I just checked the Clymer manuals that I have for 650 and 850. They both say to position the lobe pointing up, measure, repeat as necessary.

My Suzuki manual (for 850) says to position the exhaust cam so the outer lobe (1 or 4) is pointing UP, the inner one (2 or 3) is pointing FORWARD, measure BOTH clearances without moving anything. On the intake cam, the outer lobe will be pointing UP, the inner lobe will be pointing REARWARD.

I have found it easiest to start with EX 1&2. After measuring them, rotate the crank 180 degrees, measure EX 3&4. Rotate the crank another 180, measure IN 1&2, rotate a final 180, measure IN 3&4.

Since you have just done this, the information is still fresh in your mind, so let me take this opportunity to invite you to ask for my valve adjust spreadsheet. It's a handy tool to keep track of your valve clearances from one service interval to the next, and will help you figure out what size shim you need. Details are in my sig.

.

[fatnfast]

Thanks Steve, I have sent you an email.
Whilst I was checking them I tried both methods out of curiosity (doesnt take long, so why not).
On one valve (no1 cyl. exhaust) I was just able to measure 0.03mm with the lobe pointing up (clymer method), but I could'nt get the feeler in using the Suzuki method with the lobe pointing forward. I guess it will run quieter with the clymer method, so I think your theory is right Nessism .