Going CRAZY with worry after valve check

[Kara25]

Hello all I have a problem with my Gs550e. First of all I want to get out of the way that the bike was running normal before checking the valve clearances only thing that prompted me to check them was that i started to hear ticking and thought that I am starting to get loose on some valves. So I opened the cover measured my clearances and true enough I have some 0.12 readings and one valve checking at 0.15mm. After seeing those numbers and deciding to order some shims I wanted to keep riding the bike until the shims arrive. After I put everything together I used my external tank to fire it up ( always do it if I do some maintenance) to eliminate having to remove the tank again in case of a problem. And low and behold the bike is difficult to start and even after raising the idle it starts but runs rough like running out of gas or the carbs being out of synch.! Is it normal just from removing shims and putting them back at their places a normal running engine to have carbs suddenly go out of synch or something like that??? Sorry for the long message but please any info to give me some peace of mind.!

 

[Steve]

Putting the same shims back in will not affect carb sync. However, if you DO change shims, you should check the sync.

Regarding your "extra" clearance: did you check the clearance with the cam lobes in the proper position?
They do NOT get checked with the lobe pointing away from the valve, which is the normal intuition.

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[Kara25]

Steve thanks for the quick reply.! All the measurements I got was with the way of starting from the No1 exhaust lobe being parallel to the head and the No2 exhaust being upwards and then continuing with the procedure as described on the manuals or even Basscliffs website! Could it be that I put the valve cover on top of the engine without screwing the small triangular breather piece on top?? ( I am desperate to determine what could it be to make the engine suddenly run rough)

 

[Steve]

You used an external tank. Did you plug the vacuum line on carb #2?

 

[Big T]

Steve, or is it carb #3?

The 550E started in1978

Kara, please update your signature with the year and model of your 550, so we don't have to guess.

 

[Kara25]

It?s an 1980 E model. Steve the vacuum line is always plugged on the bike from the moment I bought it. The previous owner not wanting to deal with the vacuum operated petcock I guess plugged it and used a manual fuel valve to close and open the flow of fuel to the carbs while parking the bike or running it. So in other words the triangular piece with the engine breather hose is not doing some interference with not being on top of the valve cover I guess??

 

[chuck hahn]

Me thinks one cam is a tooth off

 

[Kara25]

Chuck how is it possible that the chain jumped a tooth and threw the timing off?? In the evening I measured again the chain links from the arrows on the cams and they were OK. 20 if I remember correctly (it?s been 1 year since I did a top end rebuild so my memory is rusty) so I doubt that happened. One thing that I would like your expertise.. In the past when I was doing some maintenance and the bike was immobile for more than 10 days WITHOUT fuel on the carb bowls I remember having to <<tap>> them when I put gas on the line because the floats where stuck. Can the opposite happen and the floats stuck close and starve the bike from fuel???

 

[Nessism]

Unless you took the cams out the timing should be fine.

Check things like the spark plug wires and coil wires. Wonder if you knocked one of the coil wires off and now the bike is running on two cylinders?

 

[Kara25]

Nessism thank you for your input I already checked everything going to my ACCEL coils all look good also checked for spark and got big fat blue one in each plug. I am leaning towards something fuel related bcs the bike sounded like sputtering-struggling for gas. Anyway I will wait for my shims put them in and I will update for any news

 

[Steve]

Steve, or is it carb #3?

The 550E started in1978

Good point, Big T. :encouragement:

I only saw a mention of shims and knew it was not '83 or newer. :-\\\

... the triangular piece with the engine breather hose is not doing some interference with not being on top of the valve cover I guess??

No, that breather cover will not have that much effect on how the engine runs. There might be some oil vapor coming out of the cam cover, but it won't run any differently.

Can the opposite happen and the floats stuck close and starve the bike from fuel???

Yes, it's possible. I just fixed an 850 project bike that would not go over 80mph. It seemed to idle smooth enough, but felt a bit weaker than my 850. Found that one needle was stuck closed. Replaced it, went out for a test ride and had to do some math with the tach reading to find that it now goes to over 100 rather easily.

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[allojohn]

Just a note here Kara25, valve clearances get tight with wear not loose. If your valves are loose they have been that way or looser for a while.

 

[Kara25]

Allojohn thanks for dropping in! I understand that the valves get tight with use same thing happens also to the valves of my single cylinder BMW R26 (but it has screw adjustment valves). So using this logic is it safe to keep riding and don?t reduce the clearances in the valves that I have for example 0.12mm gaps and at the one with 0.15mm and that with time the engine will reduce the clearance by itself??

 

[Steve]

Many of us will extend our clearance range and go to about 0.10mm. The 0.12 might be OK, but the 0.15 is pushing it. I would just change one shim size there to take it to 0.10.

.

 

[Kara25]

Steve what are your thoughts on the fact that some shims seem OEM (like hardened surface) and other ones look bright shiny ones?? I assume they are aftermarket?? Also those <<shiny>> ones look like they have scratches on them but the lobes are all good

 

[Nessism]

Many of us will extend our clearance range and go to about 0.10mm. The 0.12 might be OK, but the 0.15 is pushing it. I would just change one shim size there to take it to 0.10.

The valve clearance spec for Kawasaki KZ1000-1100's is .05-.15 mm and they use a shim over bucket design just like GS bikes. In fact, Suzuki copied the KZ engine when designing the GS engine family. While I don't normally recommend .15 clearance for GS bikes I feel they are safe to run for guys that won't be racing.

 

[Kara25]

Final update.! Changed two shims the ones with 0.15mm clearances-brought them down to 0.10 put new cover gasket etc and fired right up! Smooth and silent engine now. thanks everyone for the help!

 

[Steve]

Thanks for the update. :encouragement:

.

 

[wymple]

I'm still not understanding how the .15 mm clearance caused any running issues. Too tight, yes, a little loose, no.

 

[Steve]

Oh, it will run, but you will have less valve lift and less duration, so performance will be a bit less than it should.

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