'82 GS850L Stalling problem

[frosty5011]

Hey Frosty....
Dropped the bike off back at the mechanic last night. Finally, she crapped out right in front of him, and he saw my problem. We ran the bike at idle super-hot, and he has a laser thermometer. Three headers registered about 145-150 degrees, while one was only at 90-95. He's going to adjust idle mixtures on all 4 carbs, but he really thinks its an ignition problem more than a fuel problem now. Under my side cover, there's a little black box with a bunch of wires coming out. Think its some sort of signal generator telling stuff when to fire, or something. Somehow a 1980 GS1100 box ended up in my 1982 GS850! Don't remember putting it there myself, and never had any work done on the bike 'til now, so its somewhat of a mystery. Anyway, mechanic says these thingys do go bad after a while and send weak signals, so he's ordering and installing a Dyna S in the engine side cover to improve the ignition firing, or pickup signal sending, or whatever. Leaving the original coils for now, as they seem OK. Hopefully this will do the trick. I'm into the bike so far for $900 (rebuilding carbs, rebuilding front forks, installed braided brake lines all around, rebuilt front master cylinder, new front pads, new battery, general tune up and fluid changes, new Sylvania H4 bulb, state inspection, and miscellaneous new shiny stuff from Flat Out Motorcycles. Another $200 this week for the Dyna S installed, and I pray its finished. The guys not killing me on price-seems pretty reasonable for all the parts & labor, I just want to stop the bleeding! If all goes well, I'll be back on the road by mid-next week. If all REALLY goes well (and the wife OK's it) maybe I'll see you in West Virginia next year. Close to you, but a hike for me.........

That is not an area in which I am very knowledgeable, I've never had problems with any of my signal generators/ignitor boxes, etc.

Others here are more knowledgeable about this area than I am, but I would have thought that if the problem did lie in that area, that your bike would not be, as you stated earlier, running flawlessly.......with the only exception being that it would sometimes stall out on you when you brought it to a complete stop. I could understand that, when it's on it's way out, it (signal gen/ign box) might start to act up when it got really warm, but then it should be noticeable during riding too. Either a signal is given to the coils to generate a spark, or it isn't......it can't signal the coils to give a "weak" spark. If you're getting a weak spark, then the problem lies elsewhere.

But like I said, this is not my area....hopefully someone else can help you out. I just think the key is what you stated earlier: (1) the bike runs like new /strong when you are riding it, only exception is the stalling out at a complete stop (2) plugs are powdery white, and (3) idle speed raises 400 rpm's when warm/hot.

I don't know how much has been shelled out to the mechanic total yet, but I would definately question some of his advice.

[t3rmin]

Rocketman: What did the resolution end up being on this issue?

I've got the same thing going on right now. Runs GREAT until warm, then starts to stumble and eventually stalls. Spark is erratic on #1 and #4 cyl and I feel a slight shock when grabbing the #1 boot when "it" is happening (although visually the boot looks great).

I already have a brand new Dyna S, so I'm sure I can resolve this with new coil(s)/boots/wiring/fuse/etc. (basically going through and checking the whole ignition). Just wondering what fixed it for you, though.

Thanks.

[Rocketman]

Thanks for asking. For a while I thought I was boring everyone here with my problems. As it stands now, carbs have been rebuilt and synched to perfection three times now; entire ignition system is new, including Dyna S, battery, plugs, wires, boots & Accel coils. Checked every single solitary electrical connection & ground, and all is well. Nice strong steady spark on all 4 wires. Stalling problem when warmed up is now gone. Newest issue is after really warming up (15 mins to 1/2 hour), bike sputters a little on acceleration (doesn't happen when cold) but runs smooth and strong all the way up to 70 or 80 mph+. No backfiring, no hesitation, no nothing-just perfect. Plugs are a little brown around the circumference, and kind of a tad dusty white on the electrode. Idle mixture screws are supposedly 3 to 3-1/2 turns out, as per my mechanic. When I got home last night after about an hour cruise, headers 1, 2 & 3 were wicked hot, but header & pipe 4 was cool enough to not feel hot, except for the radiant heat from the engine. Now I am baffled again. No air leaks, checked boots, air box, etc. Maybe I'm supposed to live with 3 cylinders at idle for the rest of my useless life???? Can't imagine the bike would even get up to 80 mph on 3 cylinders, so I'm assuming I'm running on all 4 at throttle.
Well t3rmin....you asked!

[t3rmin]

Well as to the specific stalling when hot problem (just this thread), what seemed to be the resolution? The new coils? The new Dyna ignition? Wiring?

As for your cold #4 pipe, are you getting spark at idle? At higher RPMs? Yanking the wire off the plug, putting a spare plug on the wire, and cranking it (or twisting throttle while it's running) while holding the plug against the engine head (to ground it) will let you see if there's spark or not.

[Rocketman]

I wish I could give you a specific answer my friend, but I really don't have a clue. I took the advice of all the guys on the forum, and looked for electrical, fuel, ignition, and carb problems, and just went one by one until I replaced or rebuilt everything. So I really apologize in not being able to give you the "cure-all" but (unfortunately) process of elimination (of parts and my wallet) was the solution. But I'm not quite sure I'm 100% cured. I think I was stalling previously when one cylinder stopped firing at idle, and the stock coils were too weak to keep the bike idling on 3 cylinders. Now I STILL have cylinder #4 apparently screwed up, but with the Accel coils putting out 40,000+- vots, the other 3 cylinders keep going. I pulled wires, caps & plugs off cylinder #4 last night, and have great strong spark, no fouled plug, just more confusion. Wish I knew someone local with a sync guage or mixture guage so I could dignose rich vs. lean in cylinder #4 without buying one of these and having it rot away in my toolbox later. (Tarbash-if you're out there....you got one?)

[joejeweler]

Where are your SS Brake Lines Coming From?

Rocketman,.....where are you getting your SS brake lines from? I'm still looking and one place wants me to send the rubber ones on the bike now to match them up.

As the bike is stock,......i didn't want to loose any riding time before winter hits,.......so i'd prefer to order from someone who already has the dimentions and proper ends already attached.

Just as a follow-up to our last conversation, I think I have some good news. Brought my bike to the mechanic yesterday, explained my stalling problem, and discussed all the possible solutions you GS-ers offered. He took the bike out, went up to 8K rpm's in 2nd gear, came back with a fully warmed up bike and it was idling perfectly at 1400-1500 rpm. He claims that even though carbs have been rebuilt and synced, and even though tank was shiny clean as a whistle inside, all it takes is one thin hairline piece of shellaqued (?) gas clogging up a jet, or one old piece of carbon laying around for the past 8 years to screw things up. He asked me to be patient, get 300-400 miles under my belt since the rebuild, and to blast the bike out once in a while 'til then to bust loose any old sediment to be burned up and blasted out the exhaust. He says bike naturally should idle 1000-1100, and 1400-1500 when smokin hot at idle, and that's just what its doing now. \\/ Guess I just never had much cause to run at redline, mostly just cruise at 3-4000. Still waiting to get bike back later this week with new s/s braided brake hoses, then time to hit the road again, and hopefully not to stall again. Will update as we progress.
Rocketman

[Rocketman]

My mechanic ordered and installed them for me. You can certainly call him at 631-249-7427. His name is Chuck, and he owns Chuck Wagon Racing in Farmingdale, NY. Open Tuesday through Friday 10->6:00; Saturday 10-3:00. Prices were very reasonable, and would have gotten new banjo bolts, but mine were in fine shape. I went with chome braided with clear covers as they looked best. If you have an '82 850, I'm sure he'll know exactly what to get for you. Just tell him Larry sent you.