Testing an igniter

[Epic_username]

Hi all,

I just finished swapping a GS450 motor into my 82 GSX400. I got about 10 minutes of overall runtime before I lost spark on both sides.

My pickup coils seem ok. My ohmmeter sucks, but they both have resistance and they are both the same. Wiring seems ok. If I supply voltage to each coil separately and tap the negative side to ground, I can make spark, so coils seem ok. That leaves me with the igniter box.

They aren't cheap, so I was wondering if there was any way I can test the igniter box, so I know for sure that's it before I replace it?

Cheers!

[tom203]

Obviously test the connections from pickup coils to ignitor and on up to ignition coils. But it appears you got a faulty ignitor. Consider opting for dyna setup....image.jpg

[Gorminrider]

Edit: I see a very similar thread a few down from this so look at that too.

The Haynes manual hasn't got much but there's a test in some real Suzuki shop manuals...one of which is in the "GS250-300... pdf" available on bass cliff's site..It's a way to duplicate the signal that the signal generators create...to do this, you can disconnect the signal generators and substitute a multimeter on the ohms scale..(a penlight battery might work too) Connect the negative probe to B/W and the positive lead to either the G/R or G/W (though the colour code on the signal generators might vary, B/W will not...)
With the key and Kill switch to ON, Touching the ohmeter probe to one or the other should create a spark on one or the other spark plug...which I repeat are themselves well grounded to the engine fins....

AND/OR you might try to disconnect the signal generators, spin the engine , and with the multimeter set to Volts ,see if the signal generators are indeed producing voltage pulses for the ignitor to use...because, though the coils may test fine, the magnet that energises them may be poor...unfortunately, cheapie digital multimeters might not be so great at this versus the analogue type that jump when a fly rubs it's legs together, but something will likely show. Try turning the mainshaft backnforth past the signal generators by hand too. It might do better.

Boilerplate:The ignitor boxes can be damaged when you test for spark where the plugs aren't well-grounded. Likewise the short B/W (Black /white stripe) must also be cleanly grounded...and the TCI has its own power requirement from the O/W (Orange/white stripe) wire that also feeds the coils so check those connections too.

[salty_monk]

The clymer manual has some tests. One involves connecting up an AA battery and reading from a meter... I don't have the page here (I have it in a 1000G manual - not sure if all are the same..)

[bobgroger]

Check the connections to the Ignitor as well. I had intermittent spark on a GS1100, turned out the PO packed the connector for the pickup full of dielectric grease, which is a great insulator. Cleaned it out, tightened the connections, many miles ago.

[Epic_username]

I've always checked for spark with the plugs well grounded. I was on a ride around the block and it cut out during a 2-3 shift and that was all it wrote.

I have a cheapo analog multi-meter here at home (my nice meter is at work and hour away and I have the week off) and I was getting a smidge of movement from the signal generators. To eliminate it, I tried the signal generators and rotor from the 450 (I used the 400 stuff originally cause it had a mechanical advance, and the 450 was fixed) with no difference.

Connections seem ok. I went as far as to have everything plugged in as normal, back probed each coil negative one at a time at the ignitor connector, on the ignitor side, and tapped it to ground, and again each one sparks, so seems like my wiring is good. I also verified power to the ignitor this way, my ignitor has a separate ground wire with a ring terminal. I had wired it directly to battery negative to eliminate that during testing.

I plan to make my way to the local bike salvage with my ignitor and I'll try to match one up. Beyond that I like the look of the Dyna S system for the price, compared to a new ignitor

[fastbysuzuki]

There is a test procedure here http://members.dslextreme.com/users/...0G_Ignitor.pdf

[Gorminrider]

seems like you've done everything you can do..

Roger that, fastbysuzuki...I'll copy and paste just the ignitor test here-it's for a 100G and the ignitor casing is slightly different but the principle will be the same:

"............
16) The next step is to prove whether the igniter is powering your coils. Remove all 4 spark
plugs and connect the HT lead caps to a spark plug #1, #2, #3 and #4 then ground the plugs
and locate them to enable you to see the spark. Ensure all the connector plugs are back in,
except the one with the green and blue wires from the signal generator.

17) To simulate the small voltage generated by the pickup coil, prepare an ordinary 1.5V dry
cell with two wires red for positive and black for negative. Connect the negative black wire
from the dry cell to the blue wire on the connector plug going into the igniter. Switch on
the ignition and kill switch to power the igniter and briefly touch the red wire from the dry
cell positive to the green wire connector going into the igniter. You should see a spark on
plugs #1 and #4 when you touch the wire and on #2 and #3 when you remove the wire. If
this works your igniter is in a working condition............."

[Epic_username]

Tried the AA battery test today and no sparky-sparky. Time to find an igniter. Cheers!

[John Park]

Tried the AA battery test today and no sparky-sparky. Time to find an igniter. Cheers!

There are two main types of ignitors; those with electronic advance and those that need a mechanical advance at the rotor. Pre '83 was mechanical and post is electronic. The latter should have come with your bike but the 450s '83 on as we got in Canada are electronic. The later type are far easier to find and newer, and a GS500 setup will fit, but you will have to get the appropriate plug and wire it into your harness to receive it.

I'm still running mechanical and like it but will probably switch when/if it goes. A voltage regulator that goes south can sky the voltage and that has been held to be responsible for some ignitor failure. So there's a bit of analysis to do before buying something. Of course checking the charging system requires running the motor which requires a functional ignitor which.......

It seems like the GS500 ignitors don't fail very often, probably because electronics got a lot better after the '80s.

[Epic_username]

That's good to know, since I have both the mechanical advance pickup set and the fixed set that gives me options, as long as I can come up with the appropriate connector.

I didn't know that about the regulator. This regulator isn't original to the bike, I googled the part number it had on it and it came up as a Honda CB piece. I never thought to check the output of it.

[John Park]

That's good to know, since I have both the mechanical advance pickup set and the fixed set that gives me options, as long as I can come up with the appropriate connector.

I didn't know that about the regulator. This regulator isn't original to the bike, I googled the part number it had on it and it came up as a Honda CB piece. I never thought to check the output of it.

There's times when I'd be happier with just two wires coming up from a set of points to the coils, but so far I've had zero problems with the old '82 sparkbox. I'd be seriously considering going GS500 parts because you can find those a lot faster if it goes pffft in Pavement Narrows, Montana. Plus you have the option of going new [horrors!] if you need to.

I wouldn't be in a hurry to throw that ignitor out, either. If the voltage drops below maybe 8v they cease to spark; at least that's my experience. If the stator isn't putting out - all too common - your battery may have just dropped too low or there is a wiring fault. It's an expensive conclusion to jump to.

[Gorminrider]

If it's too hard to find an ignitor, (but maybe likely they used the same one for lots of Suzukis..?)
...I sort of wonder if you couldn't slap a set of points from an earlier GS in there...it all looks so similar and one wonders just how much Nippon Denso and Suzuki actually changed when they went electronic...looking at the Clymer, which covers back to the earlier 400s, the advance is not so different? about 10 degrees? so possibly turning the point plate a bit more might work...

[John Park]

If it's too hard to find an ignitor, (but maybe likely they used the same one for lots of Suzukis..?)
...I sort of wonder if you couldn't slap a set of points from an earlier GS in there...it all looks so similar and one wonders just how much Nippon Denso and Suzuki actually changed when they went electronic...looking at the Clymer, which covers back to the earlier 400s, the advance is not so different? about 10 degrees? so possibly turning the point plate a bit more might work...

Finding an early 400 points plate, advance mech and a decently made new set of points would usually be more difficult than getting a GS500 setup off ebay. It's been forty years, and I'm amazed at how the parts the pre '80 twins have dried up. Given that an electronic drops right into a points bike, going the other way should be equally straightforward. And I think the GSX400s ran 20 -40, and the early 450s 15 - 40, and 10-40 on the old roller motor may have been to save you right leg in case it kicked back on you. By 4k they're all the same; 40 degrees.

The big difference between a twin and a four ignition system is the number of HT leads coming off the coils. You may know what bike the ignition is in, but the system just processes electricity. All it sees is signal and load.

For that matter, an 'acoustic' ignition off an old four should work on a twin and may be easier to find.

[Gorminrider]

^^True enough- I was just thinking that when I'm casting about, it's a matter of luck...one never knows what will show up first, so all options are good to know...