My official testing of several different aftermarket CDIs

Venice Motor Bikes said:

Again... if you go back & thoroughly read the entire thread, you'll find the answers to most of your questions.

In my 16 years of building (& racing) these engines, I've never seen one that had such high compression that a stock box couldn't adequately handle... I've only seen a few engines that the Gasbike CDI worked a little better on because of it's milder timing curve & stronger spark.

& to be real honest... I'm skeptical of these 'high performance CDIs that that look like nothing more than a stock CDI molded in a different color plastic & a fancy wire.... Because there are lot of sellers out there selling snake oil.


So anyways... I'm kinda done being the only guy to waste his time on this subject... (I already posted what I've learned).

I'm inviting you to 'pick up the torch' & spend your hard earned money & time buying all the newest CDIs & testing them on different levels of performance engines... & then you can post your results here for everyone to question & criticize; (as they did to me).

Good luck, & we're all looking forward to reading your test results!

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Venice Motor Bikes said:

Here's some of the different aftermarket CDIs that I tested with the results...

*edit*>>> The numbers posted are the total advance degrees @ 3000 RPM, & the 'number of turns' is the total outward turns on the coil voltage tester.

All the CDIs that I tested (even the stock Chinese black boxes) have a advance curve of roughly 25-30 degrees.

Most of the stock Chinese boxes maxed out around 5-10 turns, (but one particular Chinese box maxed out at a whopping 20 turns)!!!

My 12v timing light was having a bit of trouble reading the 6v sparks at low RPMs, but I was able to see quick flashes of where the timing curves started.

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Gas Bike just re-named this the 'Super Rocket' CDI


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Gas Bike just re-named this the 'Thunder' CDI.

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Venice Motor Bikes said:

Again... if you go back & thoroughly read the entire thread, you'll find the answers to most of your questions.

In my 16 years of building (& racing) these engines, I've never seen one that had such high compression that a stock box couldn't adequately handle... I've only seen a few engines that the Gasbike CDI worked a little better on because of it's milder timing curve & stronger spark.

& to be real honest... I'm skeptical of these 'high performance CDIs that that look like nothing more than a stock CDI molded in a different color plastic & a fancy wire.... Because there are lot of sellers out there selling snake oil.


So anyways... I'm kinda done being the only guy to waste his time on this subject... (I already posted what I've learned).

I'm inviting you to 'pick up the torch' & spend your hard earned money & time buying all the newest CDIs & testing them on different levels of performance engines... & then you can post your results here for everyone to question & criticize; (as they did to me).

Good luck, & we're all looking forward to reading your test results!

Click to expand...

Wevil Kenevil said:

This is what I use. Mine has lasted me several years and paid for itself over again.

It's @$25 bucks

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CatNip High Performance Racing CDI Coil + OZ MAGNETO 80cc/66cc Motorized Bike | eBay

CatNip High Performance Racing CDI Coil 80cc/66cc/48cc Motorized Bike Bicycle. Condition is New. The CatNip High-performance motorized bike CDI greatly improves spark and increases power on two-stroke bicycle engines 80cc/66cc/48cc.

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