mustering the confidence to do my valve adjustment

[MikeS]

Growler said, "Can this be done during winter? It's right around freezing here these days....should I wait until spring?"

Uh oh. I didn't think of this. I'm getting ready to do my valves for the first time and I didn't consider just how cold it is here this time of year. Oil could be so congealed that it's hard to separate the shims to get them off, plus other temperature related unforseen problems? It just makes sense now that I think about it that static clearances are going to be different in the lower temperatures of winter than in the summer. (Although I've nowhere seen it mentioned, I'm assuming the clearances are measured with with an engine that hasn't been run in at least 12 hours.)

So . . . maybe I too ought to wait until Spring. Temps here are routinely falling into the 60's during the day and of course it's bitterly cold when the sun goes down - currently in the low 50's at night. Some people think it's warm all the time here in San Diego. Ha. My garage isn't heated. Can this job be done in such frigid conditions or is it foolish to try doing this job outside of a heated shop?

Mike
1982 GS850G
1979 GS850G 72K miles with bad head gasket parts bike

 

[Steve]

You MUST be kidding.

Many of the guys here would kill to have their workshop heated into the low 50s so they can work comfortably.

I thought you were talking about "bitter" cold. That is still t-shirt weather.

Really, NOW is the perfect time to do your valve adjustment. The oil is not so coid that it congeals. That is, unless you are running straight 80w, like the Harleys do. If you are using the proper 10w-40 that is recommended by Suzuki, the 15w-40 (dino) Rotella or the 5w-40 (synthetic) Rotella that many of us use, there is NO problem at that MILD temperature.

You are correct in assuming that you do not run the engine before checking valve clearances. Some will say 8 hours, others will say 12, but you definitely don't run it before checking clearances.

.

 

[growler]

Hah, noted! We have a warm day today (around 45 degrees Fahrenheit) and of course I don't have time to do it today.

But we are consistently in the 20s-30s these days. Now that I have my bike up on a stand I realize I have a leak (or two) to deal with. I may just wait until spring to do the adjustment.

You MUST be kidding.

Many of the guys here would kill to have their workshop heated into the low 50s so they can work comfortably.

I thought you were talking about "bitter" cold. That is still t-shirt weather.

 

[eil]

This time of year, I heat my garage up to the low 50's to work out there.

 

[mikerophone]

This time of year, I heat my garage up to the low 50's to work out there.

Coveralls, knitted cap and gloves for me in the carport, no garage here. One day I'll have one.

This week last year, over the holiday I swapped the motor in my Acura, this year its been in in the low 30's already. My bike is 4 miles away from turning 10k miles, and I really want it to tick over that mark before I put it in hibernation for the winter. Come on Utah weather!

 

[trippivot]

specs ? I think it is about the noise.

specs ? I think it is about the noise.

I loved immigration canyon when I lived in your area. we did it as long as it was clear - had a ratty old 82 750 GPz those days - yeah DOHC shim under bucket - and Plaza Cycle

you guys are overthinking the valve lash -- the only rule about temperature -- is the engine not operating temp. over 100 degrees hot - I have done it hot - you may get a ticking valve after it cools off -you might be able to hear them more than normal .. you can hear air cooled bikes internal parts moving more than other engines.

the biggest thing is there IS space when valve is closed .. .001" is tighter than spec and very quiet -- .008" is looser than spec and you can hear it especially right at a cold engine start up...

I like to say, "I'd rather hear them than smell them." wide lash and true duration can be debated but the flank of the camshaft and base circle are not perfect either, so don't lose sleep over 0.001" or 2 -unless they are too tight-

 

[mikerophone]

I loved immigration canyon when I lived in your area. we did it as long as it was clear - had a ratty old 82 750 GPz those days - yeah DOHC shim under bucket - and Plaza Cycle

Love all the canyons around here, especially the ones like Emigration and American Fork that you can loop, no need to turn around. Plaza's still around. Don't go there much these days though.

Funny, just a couple weeks ago I was up in your neck of the woods, passed the Mars Cheese Castle on the west side of the freeway heading from Milwaukee to Chicago...the company I work for buys some specialized CNC cutting equipment from a company in Milwaukee and Franklin and we have offices in Chicago proper and Elk Grove Viilage so I'm out there quite a bit. Will be there all next week too. Small world!

I like to say, "I'd rather hear them than smell them."....so don't lose sleep over 0.001" or 2 -unless they are too tight-

^^ Stated perfectly. Unlike some things, a little loose is better than a little tight.

 

[growler]

So I finally started this over the weekend. Got everything tied up out of the way, breather cover off, valve cover off without any issues.

However, I am thoroughly confused reading the tutorial and determining which lobes correspond to 1, 2, 3, 4, and should both lobes of one side of engine be pointing the same direction when taking measurements? So if i'm on the right side of the bike (if i was sitting on it), those are 3 and 4 right? When I have lobes pointing forward then I am measuring exhaust of 3 and 4? Ugh. I learn visually so it's hard for me to just read the tutorial and understand. Maybe I'm making this too complicated, but i've read everything and i'm just more frustrated than before.

 

[JTGS850GL]

Download the manual from here:
http://www.mtsac.edu/~cliff/storage/gs/GS850_Manual_HiRes.pdf

Jump to page 25 and it shows the pictures of how everything should be oriented in figure 3-6.

Start with cylinders 1 & 2. Rotate the crank clockwise until the exhaust cam lobe on #1 is pointing forward and level with the top of the head's gasket surface. The #2 lobe should be pointing almost straight up. At that time you can measure/adjust the clearance on 1 & 2 of the exhaust.

Rotate the cam so that the #1 intake cam lobe is pointing straight up. The #2 lobe should now be pointing back toward the rear of the bike and be level with the rear gasket surface. Now you can measure/adjust 1 & 2 intake valves.

Go to the other side of the bike and rotate the crank so that the 3 and 4 exhaust lobes are in the same position as was on the other side. Measure/adjust 3 & 4 exhaust.

Turn crank until the intake lobes were in the same position on the other side with the #4 lobe pointing up and the #3 lobe pointing back. Now you can measure/adjust 3 & 4 intake.

Done.

 

[Steve]

Yep, JT has it. :encouragement:

The FACTORY manual explains it properly, Haynes and Clymer only say "position the cams this way to check clearances". Only the factory manual says what JT said, "Position the cams like this, measure BOTH valves on that side of the engine".

.

 

[growler]

I must be making this way harder than it is. So let's say i'm measuring exhaust clearances of #3 and #4. When #4 is in the correct lobe forward position and ready to be measured, #3 will be in a different position (as in the below photo). When I'm ready to check #3 exhaust do I then turn engine so that the #3 lobe is now forward and then measure that exhaust clearance?

 

[growler]

Or if I make enough turns both the #3 and #4 lobes will line up in the forward pointing position as illustrated in the manual?

 

[Wingsconsin]

I agree -- valves are part art and part black magic - and I WATCHED when Steve looked after mine when he helped with the top end refresh last year.
I KNOW I have to do it in the near future - and I have done valves on other bikes, but never a shim in a bucket like these.
Always before a lock nut and adjuster screw ... easier in my opinion because there is no math ..but Steve's spreadsheet does the math for you...




Double, double toil and trouble;
Fire burn and caldron bubble.
Fillet of a fenny snake,
In the caldron boil and bake;Eye of newt and toe of frog,
Wool of bat and tongue of dog,
Adder's fork and blind-worm's sting,
Lizard's leg and howlet's wing,
For a charm of powerful trouble,
Like a hell-broth boil and bubble.

 

[JTGS850GL]

I must be making this way harder than it is. So let's say i'm measuring exhaust clearances of #3 and #4. When #4 is in the correct lobe forward position and ready to be measured, #3 will be in a different position (as in the below photo). When I'm ready to check #3 exhaust do I then turn engine so that the #3 lobe is now forward and then measure that exhaust clearance?

View attachment 38735

You don't turn the engine. When the #4 is pointing forward you measure both #4 AND #3 in that position. You only turn the engine when moving onto the next pair. Just remember to NEVER turn the engine over while there is no shim in ANY of the shim holders. Some have used a coin as a place holder but I'd just use an extra shim for that.

 

[growler]

I think I understand. So when #4 is in that forward position, it doesn't matter if the #3 lobe is pointed forward, or up, etc....just measure the clearance? So all that matters overall is the outside lobe positions?

Sorry for my ignorance, just wanna get it right.

 

[growler]

I'm close to getting it. I know once it clicks I'll be quite embarrassed.

I agree -- valves are part art and part black magic - and I WATCHED when Steve looked after mine when he helped with the top end refresh last year.
I KNOW I have to do it in the near future - and I have done valves on other bikes, but never a shim in a bucket like these.
Always before a lock nut and adjuster screw ... easier in my opinion because there is no math ..but Steve's spreadsheet does the math for you...

 

[growler]

I also just ordered another feeler gauge set. The smallest on the set I have now is 0.04mm. Grabbed a set off of eBay that has 31 blades, .038mm to .889mm.

 

[Steve]

Grabbed a set off of eBay that has 31 blades, .038mm to .889mm.

Ignore those metric APPROXIMATIONS, you have a set that goes down to 0.0015".

Just to help you with some reasoning behind the cam lobe positions: you obviously don't want a lobe pushing on a valve when you are trying to measure clearance. With the lobes in the specified positions, not only is that one not pushing on a valve, the one next to it isn't, either. That keeps the cam somewhat centered in the bearing on that side of the engine. You should note that the valve goes down in the head at about a 45 (or so) degree angle, and the two cam lobes are at about 45 degrees to the valves.

Does it make more sense now? :-k

.

 

[Allie]

Steve's spread sheet is the mystic hoodoo magic that allows me to do my valves. It also serves as a record of the last time my lazy asp last did the valves. Everything else is pretty straightforward and methodical once you get used to it. Well juggling shims around can be a little creative so you order the least amount of shims necessary.

 

[growler]

Unfortunately, Steve's spreadsheet isn't my issue. The positioning of the lobes is what I need help with.