GSX750 1983 ignition (on cylinder 1) problem

[ovelar]

First post from an confused GSX750es 1983 owner.
Problem:
Cylinder no 1 not running (cold exhaust), further investigation showed no spark. For this model cyl 1&2 uses one ignition coil, 2&3 uses another.

Test done so far.
Cyl 4 - good spark
Measure between ignition cap 1 & 4 - 35 kohm which is ok according to service manual.
connect wire from cyl 1 to cyl 4, result cyl 4 not running.
switch wires(from igniter unit and to plugs) so that problematic coil connect to cyl 2 & 3 - result cyl 2 not running
removed spark plug cap on problematic coil and shorted the wire a bit, then put cap on again - no difference

What am I missing? Can a coil be half-dead? Has anyone succeded in changing the whole wire? It seems to be glue to the coil.

/Ove

[BassCliff]

Greetings and Salutations!!

Hi Mr. ovelar,

Have you replaced the plugs and plug caps yet? That's cheap insurance, even if it doesn't fix your issue. I suppose it's possible to have a bad wire on a coil. It is possible to replace the wires. You must carefully chip away the epoxy and dig out the old wire being very careful not to damage the spike at the bottom of the hole. Then epoxy the new wires in. I suppose it's possible for just one side of a coil to be bad, but I can't say that I've ever heard of it. But the, there's a lot I've never heard of.

There are more troubleshooting notes on my website in the "Electrical Odds and Ends" section.

Anyway, I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", the Carb Rebuild Series, and the Stator Papers. Now let me roll out the welcome mat for you...

Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[chef1366]

Check the resistance on the crank trigger.
Then check the ignitor.

[ovelar]

Hello again

I did check the crank trigger and the ignitor using information from service manual and BassCliff's site, found no problem.

So I ordered a new coil, It arrived today and after replacement of the old one I have a bike running on all 4.

Thanks for your help.

/Ove