Got my bike running today but intermittent coils....

[Guest]

Hey guys I got my bike running today which is the good news. The bad is I am having intermittent coils issues just on cylinders 1 and 4, the plug wires and boots are in rough shape but work. At one point I switched the plug wires from cylinder 1 to 4 and work for a bit. So the history on the bike was is that the electrical was ll torn apart because of it dying mid rid not the kid I got it from. The bike has. Dyna s ignition and when I rewired the bike I did the coil mod with a relay. All of the wiring is correct because I am a mechanic and have my ase in electrical so I know I did not mess it up, but I know that when the bike is running now it's only on 2&3 and you can unplug 1&4 and nothing changes. So I don't know if I should check the dyna for output on that set of coils or if the stock ones are junk and wires included. Also the the pickup and power wires were all poked and prodded but I fixed then so what should I do?

[metalist25]

12v at signal wire

So I just went side with a multimeter and checked for voltage, so what I found is that the right coil with does cylinder 1 and 4 has power on the orange wire which is normal, but on the white signal wire it's 12v which is bad right, because the working coil the left one has on 1v when ignition is on.

[metalist25]

Update

So I just went back out side and cut the orange wire which supplies 12 v to the coil and tested right at the pickup wire the white one which then had .005v instead of 12 v connected with the ignition on. The left side coil still had 1.05v with ignition, so maybe sort to power on the coil or a bad pick up on the dyna? But when the ignition is off the white wire would still show .005 and the good coil 000v so I am really thinking bad coil but it ran today for a short time, because i wired it right. The dyna s has 4 wires 2 red for 12 v constant and black and white for coil pick up. I spliced the two red together and hooked up the coils pickup wires to the coils according dyna wiring diagram. The re wires went to the relay on the switched power side and the relay was hooked up right because the left coil works fine. ??????????? I don't know just need some suggestion or help!!!!!!!

[metalist25]

Guys

The coils are grounded by the spark plugs correct? Just like automotive.?

[Killer2600]

The coils are grounded by the spark plugs correct? Just like automotive.?

The coils are just like an automotive waste spark ignition, that's all I can say about that.

As for your coil, have you checked for spark? Have you tried switching the coils around to isolate a bad coil or bad pickup? Those are the basics I would start with.

[metalist25]

Coils

Going today

[tom203]

Best to test ignition coils and compare them

On each coil, unscrew plug caps from plug wires, stick meter probes in these wires- should read about 12 kohm (if stock coils)
Now measure primary resistance of each ignition coil , likely be about 4 to 5 ohms (stock coils) might be 3 ohms if aftermarket. What do you get?

For this wasted spark system, the spark has to travel down one plug lead, leap two gaps and get back to coil.
Dyna ignitions can fail too, but rule out coils first.