1983 gs 750 es CDI ignitor box problems pleasee help

[Cash-money89]

hey guys been battling a problem with my bike since last summer, tired of noone around here knowin what there talkin about lol. Well here it is, the bike started misfiring, then runnin on 2 cylinders, randomly start to work on 4 then back to 2, then ofcourse completly died before i got home. Got my mechanic down, after runnin through all the wiring for the plugs n whatnot, and testing if power was going into the box, wich it was, but there was ntohin comin out. He tried changing wires, makin a few connection changes to see if he could jus jump the circuit ( keep in mind im not ttoo familliar wit these bikes) but nothign worked to get spark to my plugs.

K srry about the book but its best get everything out there, i did buy a new cdi off ebay, piece of crap the thing was shorted out already, he sold me a broken box. When i plugged his cdi box in, spark started to jump from the plug wires continuosly, and the key wasnt even in the bike lol. I cant find anyyy other CDI boxes, what do i doo i appreciate ur time in reading this guys, hope ur smarter then any of us around here haha

[mike_of_bbg]

Hello and welcome,

Let me start by saying that I have NO IDEA about your specific model, so please take what I say as general advice and follow up with research of your own.

There are a few threads discussing igniter repair, you might want to have a look at some of them via forum search. I think it's usually the output transistors that seem to take the greatest hit.

This is probably the last option you want to approach, but those igniters show as still being available new. It's going to set you back about $500 though. The 83 sig gen is unique only to that year of GS750 by part #. Not sure if any other models' ignition would work. Dyna does not show a Dyna 2k part # for your electronic-advance bike, and that would likely be close to $400 also.

http://www.boulevardsuzuki.com/fiche_section_detail.asp?section=95004&category=Motorcycles&make=SUZUKI&year=1983&fveh=2139

You might also try a forum search on retro-fitting mechanical advance and using a Dyna S ignition on your specific model. It has worked on some models, though the advance curve will not be the same.

Whatever fix you approach, the first thing I'd do once it's running again is to thoroughly check the charging system on the bike. I think the igniters take a lot of damage from high voltage when bikes over-charge. Would suck to pay $500 for an igniter and have it go bad right after replacement! No returns on electrical parts!

[mike_of_bbg]

1 IGNITER UNIT
32900-49420 (replaces 32900-31310)

alpha-sports parts cross-reference shows the superceded igniter part # (32900-49420) on the following bikes:

1983 SUZUKI GS1100GD - SIGNAL GENERATOR
1983 SUZUKI GS1100GKD - SIGNAL GENERATOR
1983 SUZUKI GS850GD - SIGNAL GENERATOR
1984 SUZUKI GS1100GKE Touring - SIGNAL GENERATOR

The original part # (32900-31310) shows these bikes:

1983 SUZUKI GS750ED - SIGNAL GENERATOR
1983 SUZUKI GS750ESD - SIGNAL GENERATOR
1985 SUZUKI GS700EF - SIGNAL GENERATOR
1985 SUZUKI GS700ESF - SIGNAL GENERATOR

Not sure why the odd changing of years. Maybe someone more helpful will be along soon to offer better options.

[Cash-money89]

Hey mike i appreciate thee welcome, and your advice, i was hoping that i could use an alternate cdi or something off another rbike, thats cheaper then the 1189$ new one that suzuki ttried to charge mee! lol nottt happenin, i was told ppl have changed the igniter units in these bikes before jus ive neevr heard anything on it, is there a wayy to rebuild the inerts of the CDI? Its glued in but i had a spare one here that came out pretty easy, could smell the fried electrical compnnents tho.

So basically its take my chances with another off ebay, if i cant rebuild it or find a substitute?

[koolaid_kid]

If your ignition system is faulty, most suggest replacing it with a Dyna S. Around $130 or so, and all ignition issues are solved. Worked for my GS, anyway.

[mike_of_bbg]

$1200 for a new one ????

$471 @ Boulevard (see the link from my second post). You can even use the code "LOYALSHIP" to get free shipping for now. Like I said though, if you can make your old one behave long enough to do some charging tests I'd do that first.

The Dyna S requires mechanical advance. As I said in my first post, some have done that: you'll have to find out which mechanical advance might be suitable. The mech units have less advance and it's more abrupt than the units with electronic advance. So, you might have to sacrifice either idle timing accuracy or upper-end timing accuracy. But it means you can use a cheap ignition like the Dyna S.

See post #7 in this thread:

http://www.thegsresources.com/_forum/showthread.php?t=177631&highlight=igniter+repair

More searches for, say, "igniter repair" might shed more light. The list of compatible part #'s gives you more potential replacements to look for on eBay.

[Cash-money89]

I know for sure everyything is fine except that black box wit those 2 lil wings on it for the bolts to go through, cdi igniter i thought its called, but yea, will the dyna s completly remove n replace that? If so then thats what im lookin for

[Cash-money89]

I see what your saying mike but what exactly is mechanical advance mean? Jus the timing kind of thing? This is my problem tho the bike wont even offer a chance at starting, theres absolutly no spark going to my plug wires anymore. It still turns over, jus doesnt even offer the slighteest catch.i see a few here on ebay for 230 n stuff but its still used. I really dont have much more to spend on a box at this time, like the 500$ one u suggested, and i really dont see the need in doing all that meessing around and loosing some top end power due to bying this cheaper dyna s system

[mike_of_bbg]

OK, I'm not sure how much you know about ignitions, so here you go:

Ignition systems spark during the compression stroke, BEFORE they reach top dead center. The combustion process takes time, and you want your best "punch" to be right about the start of the piston descent on the power stroke. As the motor turns faster, there's less time available for the combustion to take place, so ignition systems are designed with ADVANCE so that, as RPMs increase, the combustion process starts earlier. On the first couple generations of GS, that was done with a mechanical advance: as the motor spins faster, weights swing out and actually advance the rotor physically relative to the crankshaft. The electronics were designed to fire right when the rotor passes the pickups. The electronics were thus much simpler than the later electronic advance systems as on your bike.

Starting in 1980 I think and ending in 84, Suzuki switched over to electronic advance. The rotor never changes orientation with the crank. The electronics inside the igniter (technically not a CDI, though some people call them that, but that's a different ignition technology) advance the spark based on logic in its circuitry. Due to this additional circuitry (called an integrator I think), the mechanical advance is eliminated but the electronics inside the igniter are much more complicated.

On my bike with mechanical advance, the advance at idle is roughly 15 degrees IIRC, with a maximum advance of ~30 degrees at 2500 RPM. So in the space of 1500 RPM, the motor gets all the advance that it's ever going to get. In the graphs I've seen on the electronic advance modules, that advance takes place at a more gradual pace, and ends with a greater advance. Let's say your bike starts with 15 degrees advance and ends with 45 over a 4000-RPM span (just example numbers). If you time it so you get the full advance at 5000 RPM, you'll be 15 degrees over-advanced at idle. It might run like that, but lose some power. If you time it so you're on at idle, then you'll be 15 degrees under-advanced at 5000RPM. And you'll never be able to match up the advance in between. Some experimentation may be required to achieve the results best for you.

That all assumes that you can find a mechanical advance mechanism appropriate for your crank, and find a Dyna S to fit. Others have done it and have been OK with the results. Not sure about your model exactly.

See part #5 in the following diagram (from my model) for what a mechanical advance looks like:

[Killer2600]

hey guys been battling a problem with my bike since last summer, tired of noone around here knowin what there talkin about lol. Well here it is, the bike started misfiring, then runnin on 2 cylinders, randomly start to work on 4 then back to 2, then ofcourse completly died before i got home. Got my mechanic down, after runnin through all the wiring for the plugs n whatnot, and testing if power was going into the box, wich it was, but there was ntohin comin out. He tried changing wires, makin a few connection changes to see if he could jus jump the circuit ( keep in mind im not ttoo familliar wit these bikes) but nothign worked to get spark to my plugs.

K srry about the book but its best get everything out there, i did buy a new cdi off ebay, piece of crap the thing was shorted out already, he sold me a broken box. When i plugged his cdi box in, spark started to jump from the plug wires continuosly, and the key wasnt even in the bike lol. I cant find anyyy other CDI boxes, what do i doo i appreciate ur time in reading this guys, hope ur smarter then any of us around here haha

Your wiring is F'ed up. With the key off and out of the bike the coils and igniter should have no power and thus NO WAY of creating spark. If you get a mechanic to fix your wiring, get a better one than the last who possibly was the guy that f'ed it up.

[salty_monk]

There is no Dyna S for your model and no mechanical advance that will fit. You may be able to get a Dyna 2000 (electronic ignition) to work but they are expensive and there isn't one with the correct timing plate for your bike far as I know.

The GS700 from 84/85 uses the same igniter, the part number is slightly different but it the same and it works.
The 1100 one from 83 also works but has less advance in the box.

I have a tested good igniter on the shelf as a spare for my 750. I no longer have the 750 so I may be persuaded to part with it...

It does sound like you have other problems too or maybe that was a result of your mechanic "jumping" things. Not recommended with this ignition.

[Cash-money89]

Thanks salty i appreciate the time u took to actually look into this for me, cuz my knowledge on bikes electrical is slimm, and i mean he didnt try jumping anything until we found out that my igniter was gone, but yea when we got the other igniter, spark was being delivered to the wires continuously..im prettty confident that my igniter is definatly gonne, so with a new one and something is still wrong me and my mechanic will be able to figure out the rest of what we did wrong, jus tryin to get that part has been a 4 month process so far, almost a year considering i was sent a broken cdi off ebay wich set me back again.

Humm what would strike your interest for maybe parting with yours? If it wouldnt be to much trouble bud id really appreciate it, its been a full year without riding, makin me sick lol

[salty_monk]

Pm me an offer and I'll dig it out....

You need to be careful that it's not something to do with the wiring trashing the igniter box or you'll end up back where you started.
No probs to "look into it". I did the research previously when I owned the same bike.

I bought a spare for a 2,000 mile trip I went on. As you've found out, they are not cheap and it's a gamble whether what you get is really a good one!
I plugged mine into the bike and ran with it for 10mins just cable tied behind the side cover to test it.

[MAdams450]

I had a similar problem with my 84 gs1150.(intermittent spark at random times). turned out to be bad solder joints inside the igniter box. opened up my new box after about 6mos and saw the same thing starting to happen with that one also. resoldered the connections & been fine for years now. just thought i'd mention the possibility.

[tom203]

I had a similar problem with my 84 gs1150.(intermittent spark at random times). turned out to be bad solder joints inside the igniter box. opened up my new box after about 6mos and saw the same thing starting to happen with that one also. resoldered the connections & been fine for years now. just thought i'd mention the possibility.

Thanks, that's good info- should inspire others to not fear openning up a suspicious ignitor.