Cheap G9 Ignitor module

[sho305]

No way, that is awesome! People have been trying to do that for a while. I was going to try it but could not find out the advance curve, though if it has one it should work. But then I swapped motors. However I would like to put one on my clone, a magnetic pickup would be easiest. Great work!

[cinejeff]

So here is some info on how to make this work.

First off, you NEED to use a DC version of the GY6 CDI. The Yamaha engine does not have a stator to generate AC voltage used in other designs and the spark gets created from voltage from your 12v battery. These GY6 DC CDIs are used in several Chinese ATVs but are less common than the regular AC version. The DC version adds a circuit that converts 12v DC into the higher voltage required to charge the capacitor circuit in the CDI. Because there are more electronics involved, the DC version tends to be a bit larger than the AC version. Google/eBay GY6 DC CDI and you will find them no problem.

While you are looking for a DC CDI, buy a matching GY6 coil. These do not come AC or DC, and will work for both ignition systems. These coils are set up to work at the input voltages the GY6 CDIs output and give you a good clean spark. I bought mine from a north American supplier so I paid a bit more for them, but you can get these cheap from China if you don't mind waiting, about 10-15$ each. I paid about $50 with tax and shipping.

The stock ignition coil will spark with the GY6 DC CDI, but it seems too weak to run correctly in my testing.

There are several types of DC GY6 CDIs from the black brick style to the style I used that has wires coming out of a "racing" aluminium boxed CDI. They all work the same way. I liked the fact that the CDI I found had external wires coming out of it. It made it easy to cut the wires and re-solder them to the stock ignitor connector. I cut open my bad stock ignitor with a hacksaw blade around the there outside of the ignitor box, then unsoldered the stock connector.

I have included the pin outs for the GY6 DC CDI and the stock ignitor connectors. Just move the appropriate wires over the Yamaha connector. You can use spade connectors and plug them in manually, but either way, make sure you plug stuff in the correct spot.... Bad/expensive things will happen if you screw it up, especially plugging in 12v DC+ into the wrong spot... You have been warned. I double and triple check before testing it out.

On my GY6 CDI the two pin connector on the bottom was 12v DC+, the top was black (not used according to several schematics I have seen)
On the four pin connector, the two bottom connectors were green wires both for ground. The blue top left wire was for the pickup (pulsar) sensor and the top right yellow cable (sometimes can be orange) was the spark out to the ignition coil.

Looking directly at the stock Yamaha ignitor, the top left connector is the pickup (Blue on GY6), the bottom left is a ground (green wire GY6), middle top is not used, middle bottom is ground (green wire GY6), the top right is 12v DC+ (red wire on GY6) and the bottom right connector is the ignition coil (Yellow wire on my GY6 CDI).

So to recap, we need to have one ground to the pickup sensor for this to work (W/B on stock wiring harness).

I have tested this GY6 DC CDI/Coil combo on a known good G9 and it works just as well as the stock ignitor/coil in my opinion.

Hope this helps, I might make a video and post it on youtube to show everything a little better if there is any interest.

Cheers

[DieselSJ]

Awesome. Can that be used in a G2 also?

[cinejeff]

It should work on a G2 as well, only one way to find out for sure. I did some more testing on the G9 and think the timing might be off as I got some backfiring issues last night. It seems weird because it ran so great the first time I tried it on my other G9. The default timing for the gy6 ignition seems to be 12 degrees at 0 rpm and ramps up from there to about 20 degrees. I will have to adjust the timing plate to see if I can get it closer to Yamaha stock to see if it smoothes it out. If anyone has a good picture of the pickup/flywheel location in relation to the cylinder that could be helpful. If not Ill have to pull it apart to catch a closer look.

Stay tuned...

[cfherrman]

Check your throttle butterfly to see if it closes all the way for backfires

[cfherrman]

So my g2 is so bad it can barely move anymore, it misses out so bad that the engine will free spin and then fire.

I'm so reluctant to mess with my cart as I use it so much around the yard and driving in the neighborhood, now there's not much power left I have to fix this, and I also need new battery cables as you have to help it start the first time.

So I ordered a cheap dc GY6 for $7.50 which has the spark advance up to around 12-15 degrees. The 'racing' box pictured in the op's post can do a few more.

I probably won't get it done today but soon.....

[Shepard]

Here's a page full of info on hooking up various ignition modules.

http://gardentractorpullingtips.com/ignition.htm

[cinejeff]

I tried a couple of these CEOs and none really had the right timing curve. They ran but not 100%, exhaust got very hot so found a used ignitor and moved on


Sent from my iPhone using Tapatalk

[sho305]

It is best to get an adjustable timing light and time it at full advance (usually over 2500rpm), which is usually mid/high 30s degrees. If it does not run right at low rpm because of the curve, then its not the right curve. Or use a timing light that will work at higher rpm, then you know you have the correct timing at rpm.

[bbtenor1]

Do you think this might work for the g8 7 pin ignitor as well?