Ignition trouble left side

[Guest]

Hey everyone, first time poster.

I have a Gs450 that I am trying to restore and rebuild.

I have some trouble with the ignition on the left side. Cant get a spark from the coil.
I am not really electrically savvy so regard me as a child when it comes to that.

I have tried putting the right hand side coil (which sparks) on the left side but it wont spark either.
I have an additional coil from a Gsx400 (will this one work?) that I have tried as well but it wont spark either. Although when I connect them to the right hand side they all spark. I have checked all coils for resistance and the primarys are within range but the secondarys I am not too sure about.
From the Gsx coil i get around 21000 ohms but the two originals i get around 11700 ohms (too low?).
I have checked the pick-up as well but I get a reading for 139 ohms, not sure I am measuring right, measured from brown to green/white on the pick up side connector. Should be 60-80 ohms which it says in the manual.

Checked for spark (as they say in the haynes manual) on the ignition side connector between the pick up and the igniter. Unscrewed the plugs and put them on the cylinder head. Put the key in "on" position, switch to "run". And connected the multimeter + to brown and - to black/white, as well switching + to connect to green/white. They say you are suppose to see a spark between the electrode but i see nothing, from either plug.

Haven't cheched for broken wires or anything like that yet cause I dont know how to go about it or what I am looking for. Ohms? Volts? Continuity?

All help is much appreciated

[tom203]

For a guy who claims that he ain't "really electrically savvy" ,you're doing fine. Switching ignition coils around says that wiring to left coil is suspect or the ignitor itself is not firing the left coil. Here's a colored wiring diagram for 450- do your ignitor wire colors look like this? ( File takes a while to load clearly)

https://onedrive.live.com/?cid=2370B62DDF9F0C6B&id=2370B62DDF9F0C6B%211031&parId=2370B62DDF9F0C6B%211030&o=OneUp

ignition coils are real durable.

[dbursell]

They look like your chart except for the yellow/white. Mine is orange white instead.

[greg78gs750]

yeah, quit wasting your time diagnosing the coils. trace the wiring, look for breaks/etc. I agree sounds like you are doing ok. Take your time going thru the wiring diagram, it looks more complicated than it is.

[dbursell]

Will do! Good to hear that im not way off

[dbursell]

I am trying to trace wires and looking for brakes. Will it be sufficient to trace the following wires on the attached chart? 4wiring diagram gs450.JPG things that confuse me a little.

1: On the big chart that you sent me there is black/white wire going vertically over the chart in the middle and goes to ground on each side. Dont know what that is?
2. On the large chart there are 3 wires going from the signal generator. I have 4, an additional green/yellow one (majority is green with a small yellow streak). Cant figure out where this one goes?
3. There is a thing on the chart called a "starter disconnect switch" that is placed on another location than the rest of the "run" and "start" switches. What is that and where do i find it?
4. The wires going to the rear brake switch I have an additional black/white wire going to it but it is not connected, just hangs in free air and cant figure out where it goes.

[dbursell]

So I have done the following. I re-checked the signal generator/pick-ups and it seems as it was a misread from my side and it should be ok. I have measured continuity from the connectors on the left coil (the one that doesnt spark) to the ignition unit/CDI and it has continuity. I cant come to any other conclusion other than I have a half-bad CDI that doesnt send signals to left ignition coil. Am I right?

[Buddybud425]

Have you checked and cleaned/adjusted the points and wire connections on the points? I had the same problem on my 79 GS425 (very similar bikes) and that's the only thing I did differently, and that fixed my problem.

[dbursell]

You mean clean the wire ends from the igniter to the coils?

[dbursell]

By the way found this laying on the floor. Got worried that it might be something significant since it had an electrode in it. Anyone know what it is?IMG_4632.jpg

[Buddybud425]

Not the ignitor, the ignition points will be on the right side of the engine behind the Suzuki cover. Looks somewhat like this:

You will probably need a points file for this job, and file down the points so they make good contact.

[dbursell]

Thanks for the tip. I had to look it up. As I understand the 1981 gs450 has electronic ignition only and therefore have no points. I opened it up and mine looks like this IMG_4643.jpg

[Gorminrider]

this is the ignition circuit for an 81 450
I have had no trouble with mine yet so I ignore it, but I think, roughly speaking, the black box UNgrounds (disconnects) the coils when told to by the signal generators. It's a lot like points.

It sounds from your tests like the black box alright but check the wiring and connections first.

[dbursell]

Thank you for the chart. I have checked these wires for continuity and they all check out. IŽll give them one last go tomorrow and see if i missed something. Otherwise I guess i'll be looking for a ned CDI, unfortunately, since they are so expensive and hard to come by.

[phydeauxmutt]

I cant come to any other conclusion other than I have a half-bad CDI that doesnt send signals to left ignition coil. Am I right?

You are only half-right.

It is possible that you have a half-bad ignition unit, but you don't have a "CDI". CDI is an entirely different type of ignition system, Suzukis don't have it. Many people mistakenly call any electronic unit a "CDI", but the emphasis there is on "mistakenly".

By the way found this laying on the floor. Got worried that it might be something significant since it had an electrode in it. Anyone know what it is?[ATTACH=CONFIG]44835[/ATTACH]

That is one of the pins that holds a side cover on. Apparently it has broken before, the wire is there as a splint to hold it in place. That wire will help with realignment. Use whatever glue/solvent you have available for ABS plastic. Do you have ABS plumbing there? We use some for drains and/or vents, so solvents and glues are readily available.