10% power gain by motorcycle CDI/coil

I thought that replacing the standard CDI would help some but not this much! I perfected my design and got almost 10% power gain. I used to climb one street at 20.5mph but now I do so at 22.5mph. That's a gain of 9.75%. But there's science to back up this idea. (see "Devices to improve the performance of a conventional two-stroke spark ignition engine") Since 2.5% more power is derived from each 33% increase in spark power then a 10% increase of power means the new CDI has 133% more spark power! Not so amazing really considering how small the ignition coil must be to fit inside the standard CDI/coil combo. To read more about this all go to my page about Ignition Timing Changes
The CDI is now available for purchase also.

 

[Deleted member 12676]

Obviously you have never run your own business. Try it. It's a real learning experience. I used to think like you. Not now. And it's not just "circuitry". It is ingenuity, know-how, determination, life experience, risking going broke doing my own business with no back-up, etc. I spent a ton of time developing the CDI for the Grubee. That was time losing money from my other business. And cheapskates like you will burn up their engine one summer day while seeing how fast you can go and then say "golly gee-wiz I wish I'd of spent $75 on that Jaguar CDI so I would have a faster non-melted engine". Here in South America they have a saying "cheap is expensive" which means you wind up spending more money in the long run on cheap ****. Well, Grubee engines are cheap **** and they need a few things to turn them into real 2 strokes. You and I both should of bought a Morini but now we are stuck with upgrading Chinese ****. But I'm not really griping since I love a good challenge. It's been a great learning experience. Once I get my home-made expansion chamber on I'll have a video made that will make your jaw drop.

 

[DuctTapedGoat]

Actually quite the contrary - I've been doing free computer repair for around 3 years now and don't have a single regret. I've been able to keep the bills paid and at the same time I get to meet some great people that I wouldn't have had the opportunity to otherwise. That's just a high dollar that I can't justify spending, and if schematics were available for a much cheaper price I'd pick it up in a heartbeat. Maybe one of these days, but not any day soon.

No doubt that I'd rather have a Morini, but regardless of how cheap these motors are, I haven't came near to hitting the point where I've spent so much I could have bought one, so I'm not kicking myself yet.

 

[Deleted member 12676]

I'll admit that the CDI isn't essential if you aren't looking for increased performance and reliability. I just find it hard to believe that humans exist that are content with a 2 horsepower engine that can't even climb a 10 degree incline. Myself, if I can't feel some power then I'm not satisfied.

 

[Oddzball]

Heck you can get a lot of cdi's/coils to work for this motor.

I went into a offroading store the other day needing to buy a new plug wire for the HT motor. He sold me a whole CDI unit for 15 bucks, wire and all. Would plug right in if i wanted it to.

 

[Deleted member 12676]

Yes many CDIs will work but not as well because their charge capacitor and timing curve are not matched to the Grubee.

 

[SlugMan]

Just got my CDI in the other day from Jaguar. I'll hook it up next weekend. I'm looking forward to the install. I've got an aftermarket 'boarder tracker gas tank' that wraps around the top bar, so their is space under the tank to hide both the CDI & coil
I did install my new Delloroto SHA carb and high compression head. The engine will climb hills that it only dreamed about before Can't wait to see how the new ignition system performs with the other upgrades.
On these little popcorn engines, I'm not looking for speed (fixed gear), I wan't power to climb hills. I live in Maine, lots of hills!

 

[Skyliner70cc]

My bike climbs 40 deg inclines with no problem but I'm running a shifter kit bike with smaller jackshaft drive sproket going to a larger sprocket on the freewheel and a 34 tooth megagear cassette and a tuned pipe tuned for low end. It might not be the fastest but it works for me.

I'm sure someone here will reverse engineer the cdi and offer it at a more reasonable price. I'm surprised that Dax hasn't ripped off the design yet with a China made version, ala shifter kit/bmp.

 

[sparky]

Might I be able to get the dimensions of your CDI? Or a picture or something?

I do not have a "Happy Time" chinese engine, but I do have a 33cc Chinese engine.

I think that chinese ignition coils are measured in 52mm & 72mm --or-- 2" & 2.5", the distance between the "eyelets". And 1-prong or 2-prong (for kill switch)?? So what is yours?

EDIT: yea, I don't think our coils are interchangeable. Bummer...

 

[Deleted member 12676]

climbing a 40 degree incline is quite impressive!

A pic of the CDI is on my site. Just click on my signature. It only works on engines that use the same system as the Happy Time which is just the stator coil going to the CDI.