gs750 ignition coil help

[Guest]

I have a 1977 gs750. I recently put on some new emgo ignition coils and they seem to be much different than the originals. I don't know what the readings should look like when I stick an ohm meter on both the old and new coils. all I know is when I stick the ohm meter on the spark cap wires the old ones are reading 13.3 and the new ones are reading 24.3. when I stick the ohm meter on the 2 regular wires the old is reading 4.3 and the new ones are reading 4.5. please help me understand this cause I feel like an idiot at the moment lol.

[1977jonc]

also I have a dyna s ignition system. don't know if that effects it

[stetracer]

I did not know Emgo even made coils. Are they 3ohm coils? Your Dyna S requires 3ohm coils. Why did you not get Dyna coils to go with your Dyna S ignition. I don't buy Emgo product they are.

[tom203]

Ignition coils are pretty durable' so your originals are probably okOn primary side, you should look for about 4 ohms across the coil spades or some such. On secondary side, remove plug caps, stick probes in the plug wires on one coil- you probably will see about 12000 ohms. If you measure over plug caps, you'll probably see anywhere from 24000 to 34000 ohms ( the cap needs good contact with plug wire or you'll get weird results)
As mentioned the dyna coils would have been better, but stock ones will work.

[1977jonc]

I did not buy the dyna coils due to lack of funding and didn't know what to really buy. I also didn't know the PO had installed a dyna s system. I'm pretty new to the bike building so I feel like an idiot on some of this stuff lol

[tom203]

Test your original coils- they are likely good and should work adequately . Suspect bad plug caps or corroded plug wires. The dyna is nice upgrade to a points ignition system so be happy!
Most of us felt like idiots in the beginning - lots still do!

[koolaid_kid]

The Dyna S can use down to a 3 Ohm coil (electronic ignition coils, green for Dyna coils). 5 Ohm coils (points coils, black for Dyna coils) will also work, but the spark will not be quite as hot.
Emgo does not make anything. They purchase repackaged products from actual manufacturers. Quality does vary widely, depending on the quality of the original manufacturer.

[stetracer]

Sorry if I sounded harsh but I hate to see people cheaping out on parts. I know it is not my money I just feel it cost less in the long run to buy the good stuff. Every manufacture designs there products to work their components. So if you have a Dyna S then get some Dyna coils. Are you sure your Dyna S is good? If money is tight look on EBay for some good used ones

[1977jonc]

old coils still test good so might run those for now till I can afford the dyna coils. I'm not sure of how to know if the dyna s is still good? it fires and the bike will run but for some reason I have my #1 and #2 cylinders running extremely rich and the no matter how I adjust the carbs the dang things run too rich. figured it might be a plug or coil problem.

[stetracer]

Could be the choke circuit leaking extra fuel in those two cylinder

[1977jonc]

How would I go about fixing that.

[koolaid_kid]

Since one coil fires cylinders 1&4 and the other fires 2&3, I would also suspect fuel rather than fire. I am not familiar with VM carbs, unfortunately.

[1977jonc]

It ended up being a fouled spark plug