Valve clearance check on GS850

[850 Combat]

I may be way off here, rather than removing the side case to rotate the engine, when checking clearances can I remove the plugs put it in gear and just rotate the rear wheel, or is this a no no due to it being shaft driven

I do it that way. I'm just used to it from old bikes I used to own.

[Chris G]

After a bit of head scratching, and moving various shims around on paper, I think i'll be needing to get hold of four shims, as tkent02 mentioned they all appear to drop by one shim size, though No4 exhaust is in tolerance.
I have one shim marked with a X making it 2.62mm the suggested replacement is a 2.57mm are these intermediate size easily obtainable from a Suzuki main dealer?

I will put up my measurements and suggested replacement shim sizes later, for folk to confirm or not if I am heading in the right direction.

[Steve]

You might be able to get that 2.55x (2.57) shim from a member or the Shim Club, but you can not order them from any Suzuki vendor.

What you can do, though, is to evaluate the clearance it will leave you. If it will be near the tight side, just go with a 2.55 for the extra half-shim's worth of clearance. If it will leave you on the loose side, feel free to use a 2.60, as long as it still leaves you within the range.

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[Chris G]

Thanks Steve, that's just answered what was on the agenda if I could not obtain the specific shim.

[Steve]

Just get them as close as you can to spec. If you have to "fudge" it a little, go LOOSER.

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[Chris G]

Update: Needed five shims in the end, made one error in my guesstimating of how many sizes to drop, got all the new shims fitted, remeasured all the clearance and input the info into Steve's valve clearance spread sheet, had a new cam cover gasket in stock, but replaced the breather gasket all back together.
Thanks to the information available on the forum, and the use of the spread sheet, it was quite a straight forward job, still can't make my mind up if the shim removal tool is friend or foe to any new owner it is highly recommended you get these clearance checked out, as I stated before these were supposedly checked 3.7k ago they may have been checked back then but only two were in tolerance when I checked, tells me the shop just measured em up must have been on the lowest side of tolerance as usual it pays to DIY.

Ran her up on my auxiliary tank first, to warm through a little makes a change to be able to hear the tappets doing there thing, idle sounded good, now for a test ride.
Weather was not the best but a run out was needed prior to clearance check the bike was hesitant in the lower gears, and running lean this was slightly improved when I changed the o rings to the mixture screws. Well today I'd have sworn I was riding a different bike, way smoother in the lower gears, drops to idle and sits there, would be up and down before, pulls well and just feels smoother if that's the way to describe it, ended up doing 35/40 miles never missed a beat, I'll check later for plug coloration, going to run another tank of fuel using a fuel cleaner just for good measure, as I mentioned before it's only done 4k miles in the last 10yrs, roll on some good weather.

[Steve]

One more reminder: on a bike that is 'new' to you, there is an unknown service history. Even though you have just adjusted the valves, there might have been some crud on the valve seats or the valves themselves. Running the bike with somewhat proper operation now, that crud might get worn or burned away, which will change your clearances. You might want to make your next clearance check sooner than the recommended 3000 miles. Once you determine that everything is good, you can probably stretch out the interval comfortably.

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[tkent02]

I recheck them in 100 miles on a new to me bike. Almost always a few have changed.

[Chris G]

Thanks for the info fellas.

[growler]

this is the next thing on the list for me as far as maintenance. i'm not looking forward to it.

[isrl88]

It's not too bad. one of the shims has to be replaced. I can't fit the .0015 feeler gauge so I need to increase the gap

[mrbill5491]

Lol, this post has been dead for 3 years.

[isrl88]

hey do you what the steps are for removing and installing a different shim. I read the Haynes manual , is it pretty straight forward ?