1980 GS850G valve adjustment

[longgreensilverado]

here's a dumb question: if my valves are too tight due to warn out tappet shims wouldn't they be tighter if i put in thicker shims??

[Billy Ricks]

here's a dumb question: if my valves are too tight due to warn out tappet shims wouldn't they be tighter if i put in thicker shims??

It's not worn out shims normally, it's the valves that are wearing and clearances tighten up.

[longgreensilverado]

ok so if i insert my feelre guages (.03mm -.08 and it is tighter than .01mm what do i do? sorry if this sounds dumb

[Billy Ricks]

ok so if i insert my feelre guages (.03mm -.08 and it is tighter than .01mm what do i do? sorry if this sounds dumb

Pop the old shim out and remeasure the gap to see what size you need.

[Billy Ricks]

When you remove shims cover the cam chain tunnel. You don't want to be losing things down there.

[Nessism]

If there is not enough clearance to get a feeler gauge in there you are going to have to pop out the shim and go TWO sizes (or more) smaller. After installing the thinner shim you need to go back and measure the clearance again. In some cases you will need to do a further adjustment to get the clearance right. Kind of a pain but there is no other way. It would be much easier if the clearances increased with wear, but alas that's not how it works.

[rustybronco]

ok so if i insert my feelre guages (.03mm -.08 and it is tighter than .01mm what do i do? sorry if this sounds dumb

Put in the next size or two thinner shim and re-measure.
when your done adjusting the valves do yourself a favor and do a compression test.

[Steve]

ok so if i insert my feelre guages (.03mm -.08 and it is tighter than .01mm what do i do?

What do you do? PRAY. Pray hard that you have not already burned a valve. After adjusting clearances, do a compression check to make sure that cylinder is up to par with the others.

The best way to measure the valve clearances is to make a grid on a piece of paper. You need four columns for a four-cylinder bike. I like to put eight rows under those four columns.

Label row one: 1 EX.....2 EX.....3 EX.....4 EX (Remember that #1 is under your clutch hand, #4 is under your throttle hand.)
In row two, put your clearance measurements.
In row three, put the shim size.
Leave row four blank for now.

Label row five: 1 IN.....2 IN.....3 IN.....4 IN
In row six, put your clearance measurements.
In row seven, put the shim size.
Leave row eight blank for now.

Once you see what your clearances are, you can identify which ones need to change. By seeing the shim size that is already in there, you have a good guess at what needs to be there. Look around at all the clearances that need to be changed to see if any of them have the shim you need. Swap shims as necessary. I use the fourth and eighth rows to keep track of these swaps. Chances are, you won't need more than two or three shims.

When you put the shims back into place, be sure the number is facing down so the cam does not wear it off. The shims virtually never wear, so if the clearance has changed, it is most likely the valve or the seat in the head. They always wear in a manner that reduces clearance, so a thinner shim is necessary. Do not use a magnet to pick the shims out of the buckets. A magnetized shim will attract other metal pieces, accelerating wear. Better to let the metal filings flow with the oil and get trapped in the oil filter.


.

[longgreensilverado]

I'd like to start off with a thousand thank you's to all of your responses to my question.. although i am very frustrated. i measured each cylinder with a .038mm feeler and every cylinder is tight. (i made sure it wasn't sticking to the oil). also i tried removing a shim and it won't even come loose. i used a small straight screw driver and nothing. i rotated the crank so i was getting the full play i think in order to remove the shims. any ideas????

[bwringer]

I'd like to start off with a thousand thank you's to all of your responses to my question.. although i am very frustrated. i measured each cylinder with a .038mm feeler and every cylinder is tight. (i made sure it wasn't sticking to the oil). also i tried removing a shim and it won't even come loose. i used a small straight screw driver and nothing. i rotated the crank so i was getting the full play i think in order to remove the shims. any ideas????

You have to use a special tool to push the buckets down so you can remove the shims. It's only $14.95 from Z1:

http://www.z1enterprises.com/detail.aspx?ID=1696

They also have the shims for only $5 each.

Also, GET A MANUAL!!!!! The procedure is VERY clearly explained in the Haynes, Clymers, and Suzuki manuals.

http://repairmanuals.com

I would also encourage you to invest $5 in a set of metric feeler gauges. Bad things can happen if you mistake .05mm for .005 inch.

It's depressingly common to find that all or most of the valve clearances are tight on neglected bikes -- the manual calls for adjustment every 4,000 miles, but that doesn't actually happen much, especially on a bike that's been suffering from years of neglect.

I check mine on schedule, and normally only have to change one or two every second or third valve check. These bikes hold their valve clearances quite well, but you can't neglect this task.

[GaThumper]

I'd like to start off with a thousand thank you's to all of your responses to my question.. although i am very frustrated. i measured each cylinder with a .038mm feeler and every cylinder is tight. (i made sure it wasn't sticking to the oil). also i tried removing a shim and it won't even come loose. i used a small straight screw driver and nothing. i rotated the crank so i was getting the full play i think in order to remove the shims. any ideas????

Just checked in my shop manual to be sure since I'm getting ready to change mine and bouth a valve shim tool off Ebay. You will need the valve shim tool or tappet depressor to depress the tappets in order to remove the shims. Then use forceps (is that the same as hemostats?) to remove the shims. Maybe small curved needle nosed pliers will work, too?

[longgreensilverado]

1980 gs850 valve adjustment

What do you do? PRAY. Pray hard that you have not already burned a valve. After adjusting clearances, do a compression check to make sure that cylinder is up to par with the others.

The best way to measure the valve clearances is to make a grid on a piece of paper. You need four columns for a four-cylinder bike. I like to put eight rows under those four columns.

Label row one: 1 EX.....2 EX.....3 EX.....4 EX (Remember that #1 is under your clutch hand, #4 is under your throttle hand.)
In row two, put your clearance measurements.
In row three, put the shim size.
Leave row four blank for now.

Label row five: 1 IN.....2 IN.....3 IN.....4 IN
In row six, put your clearance measurements.
In row seven, put the shim size.
Leave row eight blank for now.

Once you see what your clearances are, you can identify which ones need to change. By seeing the shim size that is already in there, you have a good guess at what needs to be there. Look around at all the clearances that need to be changed to see if any of them have the shim you need. Swap shims as necessary. I use the fourth and eighth rows to keep track of these swaps. Chances are, you won't need more than two or three shims.

When you put the shims back into place, be sure the number is facing down so the cam does not wear it off. The shims virtually never wear, so if the clearance has changed, it is most likely the valve or the seat in the head. They always wear in a manner that reduces clearance, so a thinner shim is necessary. Do not use a magnet to pick the shims out of the buckets. A magnetized shim will attract other metal pieces, accelerating wear. Better to let the metal filings flow with the oil and get trapped in the oil filter.


.

Steve thank you for this. i made the chart over the weekend and figured the whole thing out. i'm a pro at it now. i just wish there was a way to salvage my gaskets. thank you very nuch.

[ccs]

ok so if i insert my feelre guages (.03mm -.08 and it is tighter than .01mm what do i do? sorry if this sounds dumb

Where did you get a feeler gauge that measures .01mm? I've looked, and looked, and looked -- the best I could find was .038mm.

Charles...

[ccs]

Steve thank you for this. i made the chart over the weekend and figured the whole thing out. i'm a pro at it now. i just wish there was a way to salvage my gaskets. thank you very nuch.

Here's a link to the chart I made up: http://www.charlescrumesoftware.com/...Shim_Chart.pdf

Charles...

[longgreensilverado]

wow nice chart. i might print it out and keep a copy. I just used basic graph paper. i have a feeler gage that only goes to .038mm. all my valves are decent at .051mm and one is at .038 almost .05mm. wow what a difference in the way the bike runs. i will definately be checking them more often. waiting 18,000 miles is too long