Igniter box maybe? Newbee here

[Anonymous]

Hi. Thank god I founbd this forum I have a 78 GS850. I got it from my dad the other day "Traided it for my camera" I think I got the better deal. The bike is awsome but unfortunatly it only fires on 2 cylinders any ideas? Only cylinder 3-4 work 1-2 just hang on for the ride and anything over 2500rpm will kill it. I serched the forum and most comon cause seems to be the igniter ox any ideas? Thanks in advance

[Billy Ricks]

It's wierd that 3 and 4 fire but 1 and 2 don't. Shouldn't be electrical if that's the case since 1 and 4 fire off the same coil and 2 and 3 do the same. Both pairs get signal from the ignitor at the same time as well. If the bike sat for any length of time you need to clean the carbs. If it sat on the sidestand then the fuel left in the lines would all run down towards 1 & 2 and you would have gummed up carbs.

[Anonymous]

Thanks I will give that a try when I get home. However I still remember about a year ago me any my father and brother tore down all 4 carbs and cleand them up real good. The bike did sit for a long time "6 years" but I am pretty sure most of it was on the center stand. Thanks for the help agan. Just to make sure you are saying that if 3-4 are firing that means the igniter box is good right? Thanks

[Anonymous]

You don't have an igniter box. If your 850 is an early one (first model year for the GS850 was 1979), then you have a points/condenser ignition. Your points and/or condenser are bad.

Electronic ignition for the GS850 first came out in 1980.

Nick

[Billy Ricks]

Even two or three months will lead to gummed up or varnished jets if fuel is left in the bowls. If 3 & 4 are firing you can pretty much rule out coil or ignitor issues.

[Anonymous]

Or he has the leads going to the wrong cylinder.

[Anonymous]

Leads going to the wrong cylinder??? OHHHH please give me more creadit than that LOL It dose have points and condenser on it. first year was 1979? I beg to differ. The placard on the front of the fraim were the forks are clearly reads 1978. I was told when I got the bike that one of the condencers was bad and that is why it would not fire on 1-2. I was also told to take the condensers and swich them around and it should start firing on 1-2 and not 3-4. If it dose not do that than it is a coil issue is that true? My nehbor took a look at it and said there was no power going to the coil that runs cylinder 1-4 but how could that be when clearly 4 is firing. oh my what a mess. After thinking it may be an igniter box I found this little black box under the right side cover that said down and had an arrow on it. I took the cap off and there were what looked like 2 small rusted coils/ relays. Dose anyone know what they are. Can anyone tell me how and were to start with my volt meter for the proccess of elimination to solve this problem. Seems I could by a new bike for what it would cost just to replace the whole ignition system. Once agan thank you for all the help.

[Anonymous]

first year was 1979? I beg to differ. The placard on the front of the fraim were the forks are clearly reads 1978.

You're obviously a newby here. I had a 1979 GS850G which had a placard on the front of the frame that read November 1978. It was a 1979 model, the first model year for GS850's. Yours is a 1979 also. I bought my 1999 Dodge Caravan in December 1998. Get the picture? You have a 79 GS850GN. (N stands for 1979).

The 1979 GS850 was unique in that it was the only 850 with points and condenser ignition, and therefore no igniter box -- which was your original question. Why an igniter box, if you knew it had condensers? Also, the 79 GS850 was the only model year that came out with old slide carbs, solid brake discs, and a kickstarter.

The little black box you refer to has to do with the turn signals and is not related to ignition in any way.

Nick

[earlfor]

Most likely, your bike was manufactured in 1978 for the model year 1979.

The condensers and points are matched to the 1 and 4 cylinder from one coil and the 2,3 cylinder for the other coil. Or to put it another way, cylinders 1 and 2 operate on separate ignition systems. If cylinder 1 fires and 4 does not, it is not your points or condenser, or coil. The problem is either the spark plug wire, the plug boot or spark plug on cylinder 4.
Remove the plugs, insert them back into the plug boots and ground them against a cooling fin and check for spark. The first thing to do is to verify that there actually is or is not a spark on which plugs.

Earl

Leads going to the wrong cylinder??? OHHHH please give me more creadit than that LOL It dose have points and condenser on it. first year was 1979? I beg to differ. The placard on the front of the fraim were the forks are clearly reads 1978. I was told when I got the bike that one of the condencers was bad and that is why it would not fire on 1-2. I was also told to take the condensers and swich them around and it should start firing on 1-2 and not 3-4. If it dose not do that than it is a coil issue is that true? My nehbor took a look at it and said there was no power going to the coil that runs cylinder 1-4 but how could that be when clearly 4 is firing. oh my what a mess. After thinking it may be an igniter box I found this little black box under the right side cover that said down and had an arrow on it. I took the cap off and there were what looked like 2 small rusted coils/ relays. Dose anyone know what they are. Can anyone tell me how and were to start with my volt meter for the proccess of elimination to solve this problem. Seems I could by a new bike for what it would cost just to replace the whole ignition system. Once agan thank you for all the help.

[Anonymous]

Ok sorry for not understanding the model year thing my car is the same way. I am a verry newbee. I have had2 bikes in the past but nothing of this scale and I have not even looked at a bike in 5 or more years. The plugs in 1-2 dont have any spark and the plugs in 3-4 have a week spark. If the wires are bad I would have to replace the coils to would I not? It looks to me the wires and coils are all one piece as on my Pontiac.

[Anonymous]

Leads going to the wrong cylinder??? OHHHH please give me more creadit than that LOL

Why? Everything you've said so far leads (no pun intended) me to believe that your spark plugs wires are not routed correctly. You keep saying 1&2 have no spark, yet 3&4 do. It doesn't make a lot of sense, based on how how the ignition system works.
There's two coils on the bike, on on the left, one on the right. I have a very simple question for you. For each coil, which cylinder is each lead going to? If you can answer that question, it would clear up a couple things for us to be able to help you.

[Anonymous]

Ok siting on the bike the coil on the left is pluged into cylinder 1-4 and the coil on the right is pluged into cylinder 2-3 I have a little update. I read about the sparl plug boots. I just went to the garage and took off all the boots. I cut about an inch up the wire and cleand out the area that the wire conects to the boot with fine sand papor. I now have spark to all 4 cylinders but still no fire in 1-2. The spark however is verry verry week for example the spark on my cars is bright blue and the spark on the bike "all 4 cylinders" are a yellowish color is that bad or pretty normal? If noone has any suggestions with this new discovery I guess I can take the earlyer problem were if the bike sat the bad gas would colect in 1-2 carbs and gum them up. right now I am going to call my father and find out exactly what we did to the carbs last year. I know we tore them all down but dont remember exactly why. Thanks for the help so far I can twait to get this thing going.

[Anonymous]

Almost forgot to ask Dose anyone have a book for this bike and if so can you tell me the spark plug and point gaps? I hope to go start searching for a book in a week or 2 thanks a million

[Anonymous]

Thanks. Sorry to jump on you, but it was confusing. Sorry if I seemed a bit harsh.
Next, check for 12volts at the coils with the ignition on. Then, clean the points with fine sandpaper and adjust them to spec. (someone else will have to provide it, my bike is electronic. Clean every contact under the points cover and at the coils.
I'd probably change the points and conensers just because. Probably the spark plugs too.
Speaking of which, what do the plugs look like? Wet or dry? what color is each plug?

[Anonymous]

The plugs are brand new. Well they were put in a year ago but the bike was not started with them untill just the other day. The plugs in the unused cylinders are well perfectly clean with the exeption of the normal stuf from taking them in and out so mannytimes and the plugs in the working cylinders are pretty dark with soot but dry