New honda coils with advancing cdi?

30500-Z5K-801 are used on generators which require at least 6200-6300 RPM to get the output. you can take it from there
A 6300rpm, generator? Powered by a big four-stroke Honda?

All this begs a question:

Why hasn't ARC or someone else just made a flywheel that will and inboard CDI system off a bike.
There is plenty of aftermarket support for something like that....
I've been asking similar questions for a long time. Now Honda's utility engines are getting linear spark curves like their bikes had 30+ years ago.

we also need fuel injection...
Small engine kits are out there. I have a MegaSquirt ECU controlling ignition on a stationary GX340 right now while I get the fuel injection put together. The commanded spark advance is not only exactly what I tell it to be, it is completely rock solid. That's with the "old" and "slow" 8-bit MS-I processor no one likes anymore. It's fun playing with the rev limiter and 2-step. :cool:

The problem is that packaging EFI on a small chassis that never had 12v charging power is tough, even with compact kits like the Ecotrons.
 

joler1302

New member
A 6300rpm, generator? Powered by a big four-stroke Honda?



I've been asking similar questions for a long time. Now Honda's utility engines are getting linear spark curves like their bikes had 30+ years ago.



Small engine kits are out there. I have a MegaSquirt ECU controlling ignition on a stationary GX340 right now while I get the fuel injection put together. The commanded spark advance is not only exactly what I tell it to be, it is completely rock solid. That's with the "old" and "slow" 8-bit MS-I processor no one likes anymore. It's fun playing with the rev limiter and 2-step. :cool:

The problem is that packaging EFI on a small chassis that never had 12v charging power is tough, even with compact kits like the Ecotrons.
Exactly! My dad talked about installing a generator to the rear axle, but that sounds like power loss to me?`
 

Oldschool00

New member
By the time yall get all that figured out, I will have done wore out all my tires, engines, and have a pile of money, with my old carb and mag ignition......
 
Exactly! My dad talked about installing a generator to the rear axle, but that sounds like power loss to me?`
An alternator/generator is going to absorb engine power no matter where the power is taken from. The other option is to carry a battery and run a total loss system that has to be recharged between runs provided there are batteries small and powerful enough to run a whole EFI system long enough for a race.
 

joler1302

New member
An alternator/generator is going to absorb engine power no matter where the power is taken from. The other option is to carry a battery and run a total loss system that has to be recharged between runs provided there are batteries small and powerful enough to run a whole EFI system long enough for a race.
Wont work for us. We drive endurance racing, with 3 persons per kart, lemans style...
 

WinstonSmith

New member
In the now that new Honda coil will do quite nicely with a proper flywheel.

ARC when can you start to make them?
Or will I wait for a PLV......
 

joler1302

New member
Just get the arc flywheel and have a machinist cut a new keyway that matches the new one. Then it can be used on both static and cdi ignition!
 

rkcarguy

New member
SO am I understanding that the coil doesn't advance, but instead removes retard as the RPM's come up? Which is essentially the same thing just a different way of getting there?
 
I don't think the old "CDI" or "magneto" or coil or whatever they are properly called is intended to retard ignition with RPM. It just fires a spark when the field collapses in the coil and that takes a finite amount of time to occur. As RPM rises, the crankshaft "outruns" the spark by an increasing amount in that time period, thus the spark fires fewer degrees before TDC.

The new digital ignition actively advances ignition timing in response to RPM up to the point that it detects an overspeed condition.
 

Kart43

Active member
They have a range from 10 to 20 degrees, they are timed at 20* static, electronics sense the turning RPM, at low RPM and starting the coil is retarded to it's lower range as the RPM build the electronics allow the timing to advance to the 20*, I bet when the intended RPM is exceeded the coil may start to act as Shelby stated.
 

WinstonSmith

New member
SO that really is all there is too?

I don't often use a key at all....
So I could simple index the flywheel to where I want it and run.

Thanks!
A few more confirmations of this would be nice however...
 

WinstonSmith

New member
I don't think the old "CDI" or "magneto" or coil or whatever they are properly called is intended to retard ignition with RPM. It just fires a spark when the field collapses in the coil and that takes a finite amount of time to occur. As RPM rises, the crankshaft "outruns" the spark by an increasing amount in that time period, thus the spark fires fewer degrees before TDC.

The new digital ignition actively advances ignition timing in response to RPM up to the point that it detects an overspeed condition.

The first thing you discuss is called a propagation delay.
Very good description of what happens too.

Second point you raise.
Why would you add something to retard timing when you could have just added a simple RPM limiter?
I think this is probably not an issue at all, but even the CDI will eventually face a propagation delay too.
 

joler1302

New member
I know, that the ignition is not some racing ignition, but the hard facts prove, that it is one hell of a performance gain, stock engine spec non cdi: 18 nm of torque. Stock engine spec with cdi: 21 nm of torque. Just putting it out there.
 

WinstonSmith

New member
No convincing required.

I'm going to try it.

I just wonder how to set it up.

Base timing at 20 deg idle?
Will that yield 30 at 3600 rpm and stop?

Looking at this i don't quite know for sure.
it would be nice of it did not start to advance untill 2500.
 

joler1302

New member
No convincing required.

I'm going to try it.

I just wonder how to set it up.

Base timing at 20 deg idle?
Will that yield 30 at 3600 rpm and stop?

Looking at this i don't quite know for sure.
it would be nice of it did not start to advance untill 2500.
The blue line is GX240
Green line is GX270 & GX340
Red line is GX390

Were are just going to put it on with a stock key to start with, i think. It would be nice with some more info about this though.
 

joler1302

New member
It looks like the red line on the chart, English version?
Only have this one, i got from the danish honda dealer, but he's got something wrong, because he saids there is only 2 models, 4000 rev limit and 6000, but there is also a non rev, but i think it's because he's consulting Honda EU. How would i observe the timing curve when i have the coil?
 

Brian Boyer

New member
Thanks for this tread~ it sold me on buying an NR Racing Honda CDI non rev limited coil for my Lifan 420cc, and it works flawlessly.
 
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