1982 GS750T....Soon to be 1981/1982 GS1100T

[bikemtn]

Charged and another try. Still at 121. Added a bit of oil and it went to 175. Now I'm not sure. Dang.

[bikemtn]

Soaked the questionable cylinder in Marvel mystery oil for several days. Cleaned it out and started up. I let it run for a while and it is not smoking like it once was. Pretty sure at this point is fuel related. Which is good news. I have a creeping idle likes to go up to about 2000 and hang. Exhaust is really gassy. Besides the obvious air leak from boots which are new by the way I am tempted to tear these carbs off again. It is vacuum synched. I sprayed WD-40 all around the boots and it does nothing to the idle.

[80GS850GBob]

Soaked the questionable cylinder in Marvel mystery oil for several days. Cleaned it out and started up. I let it run for a while and it is not smoking like it once was. Pretty sure at this point is fuel related. Which is good news. I have a creeping idle likes to go up to about 2000 and hang. Exhaust is really gassy. Besides the obvious air leak from boots which are new by the way I am tempted to tear these carbs off again. It is vacuum synched. I sprayed WD-40 all around the boots and it does nothing to the idle.

You check the vacuum diaphragms? If you installed new boots {and o-rings I'd hope} and that's all good, I'd look to the 4 diaphragms as a possible reason for the slow raise up in idle.....floats good?...height and not full of fuel?

[bikemtn]

You check the vacuum diaphragms? If you installed new boots {and o-rings I'd hope} and that's all good, I'd look to the 4 diaphragms as a possible reason for the slow raise up in idle.....floats good?...height and not full of fuel?

Diaphragms are all brand new, boots are new, new o-rings in all the carbs, 22.4 mm float height at the shoulders of the floats, no fuel in the floats. I am stumped to be honest. My valve cover leaks and I have a new OEM one to put on. So while I have it off I am going to check my valves, even though they were all in spec, and re-torque the head.
I bought all new diaphragms from http://jbmindustries.com/Dimensions.html.

[80GS850GBob]

The one thing Suzis do is increase the idle when adding choke...we sure the choke circuit isn't being slowly activated...aside from the obvious telltale choke knob being up, I was thinking of leaks in the circuit.....with everything being new that seems the place to look - to me.

Your compression test came up a lot from adding oil...maybe the rings are sticking {or worn}. I'd suggest adding enough marvel mystery oil to a cylinder, on it's compression stroke, to cover the top of the piston with a decent amount of oil. Slowly turn the crank via wrench, to mildly compress it....slowly, as in till it pushes back and then leave it and try again later. Do this a couple of times to try pushing the oil thru the rings where gravity just doesn't like doing that sometimes. You don't want to push so hard to blow a gasket. I've seen a few old engines release the rings that way...some not, but its worth a shot. Pop the plug and let it come out when done...next time it's run under power will be a tad smokey till the rest burns off/out. Try this on all four cylinders...but your compression reads aren't that bad...100psi is min. Some folks find that driving a bike for a while will loosen the rings up.

[bikemtn]

The one thing Suzis do is increase the idle when adding choke...we sure the choke circuit isn't being slowly activated...aside from the obvious telltale choke knob being up, I was thinking of leaks in the circuit.....with everything being new that seems the place to look - to me.

Your compression test came up a lot from adding oil...maybe the rings are sticking {or worn}. I'd suggest adding enough marvel mystery oil to a cylinder, on it's compression stroke, to cover the top of the piston with a decent amount of oil. Slowly turn the crank via wrench, to mildly compress it....slowly, as in till it pushes back and then leave it and try again later. Do this a couple of times to try pushing the oil thru the rings where gravity just doesn't like doing that sometimes. You don't want to push so hard to blow a gasket. I've seen a few old engines release the rings that way...some not, but its worth a shot. Pop the plug and let it come out when done...next time it's run under power will be a tad smokey till the rest burns off/out. Try this on all four cylinders...but your compression reads aren't that bad...100psi is min. Some folks find that driving a bike for a while will loosen the rings up.

Thanks! My buddy suggested checking the choke circuit as well.
I did exactly what you outlined when I did the marvel mystery soak and it seems to have worked to loosen up those rings as it does not smoke at all now. The motor sat for several years.
Like I said the exhaust is pretty gassy and there is an occasional small, quiet pop.

[bikemtn]

Your choke circuit comment has me thinking. On the 750 motor I do not recall ever having issues with the choke. On this 1100 if you fully choke....it will start immediately and the RPMs are huge...like 4000. I have to bring it down to about 1/4 choked then shut the choke off once the motor heats up a bit.

[bikemtn]

Got the carbs back on and it runs pretty nice....the idle does not hang anymore, but it does tend to creep just a bit.
The funny thing is that if I put the bike on it's kickstand it idles perfect. So I am guessing there is an issue with the floats/float valves.
It is smoking, but the motor sat for awhile and I need to put some miles on it. Saturday morning I plan to take her for a hard ride.....and kill some mosquitoes. I am sure an Italian Tune up would do it some good.

[80GS850GBob]

Right before I sold her, my H-2 developed a extra smokey pipe...found out the clutch seal was just starting to let go...plug read a tad darker. I did a leak down test like I did for the snowmobiles - 10psi with intake and exhaust plugged...if it held for 10min it was ok...said H-2 cylinder was a tad off {lost 2psi in 10min if I recall correctly}.

[bikemtn]

Right before I sold her, my H-2 developed a extra smokey pipe...found out the clutch seal was just starting to let go...plug read a tad darker. I did a leak down test like I did for the snowmobiles - 10psi with intake and exhaust plugged...if it held for 10min it was ok...said H-2 cylinder was a tad off {lost 2psi in 10min if I recall correctly}.

I think my rings in one cylinder are a bit stuck from sitting so long. Hoping some miles help.....I am optimistic.

[bikemtn]

Went for a 100 mile ride Saturday morning. Man does this 1100 have some power. Rode up to a quaint little town north of me about 35 miles....and then I extended the ride a bit to get some miles on this motor. It is still smoking, but hopefully it will subside with some miles. If not I will have to do a leakdown to see what the culprit is.


But even cooler is that I picked up a nice 2002 XR50 for my son for his 7th birthday....and he has been ripping! Loves his bike!!

[GSXR7ED]

Sweet!

Both the 1100 and the XR50.


Ed

[alke46]

Got the carbs back on and it runs pretty nice....the idle does not hang anymore, but it does tend to creep just a bit.

So what do you think happened so the idle does not hang anymore? I ask because I am having idle hanging troubles also. Got the carbs off now and re-dipping them.
Thanks,

Larry

[bikemtn]

So what do you think happened so the idle does not hang anymore? I ask because I am having idle hanging troubles also. Got the carbs off now and re-dipping them.
Thanks,

Larry

Larry,
I pulled off the carbs and checked all the boots for proper seal and did the same when I put the airbox back on to be assured that there was no air leak.
I also checked that I had proper flow in the choke circuit.
Thtottle snaps right back now.

I am not 100% sure, but I do not think I had the airbox boots to carb on good enough on the first install.
It was rather difficult to get on and I used an old broom stick and wedged it between the box and the frame to be able to push the box closer to the carbs.

Derek

[thebrandonbeezy]

man that is a beautiful bike!