Are we looking at just another "gimmick" here?

[DAMIEN1307]

I have the Zeda 80 g 4 dual plug.I use 2 cdi . I lowered the gap to .025 . Smoother over the whole rpm range. Runs better during warm up.

Welcome to the forums...Your a little late to the party on this thread...I posted what you quoted back on ...Nov 21, 2021, A year and a half ago...lol...Please look for the date codes when replying to old threads...It will help avoid the archeological digs...lol.

 

[Gkirk]

Welcome to the forums...Your a little late to the party on this thread...I posted what you quoted back on ...Nov 21, 2021, A year and a half ago...lol...Please look for the date codes when replying to old threads...It will help avoid the archeological digs...lol.

Thanks

 

[WEEDHOPPER420]

Zeda 80 has recently come out with its "Pro" edition,

New Zeda 80 Pro Complete 80cc 2 Stroke Dual Spark Plug Motorized Bicycle Engine Kit - Firestorm Edition

Your source for 2-Stroke and 4-Stroke Bicycle Engine Kits, Performance Parts, and Accessories!

www.bicycle-engines.com

2 spark plugs with a dual spark CDI unit.

I'm looking for the more experienced one's here in the forums to tell me if i'm right or wrong in suspecting this is just another "gimmick" like so many other things that have been "offered" 2 stroke users over the years claiming more torque and better high end speed etc. etc. etc. "ad nauseam".

I cannot see how you achieve much better spark when your still working off the same basic magneto's supplying electrical power to the dual spark CDI unit...I suspect that the spark would actually be weaker between 2 plugs rather than just one.
(It is the very same "improved", "upgraded", magneto that comes with the regular, stock Zeda 80, single spark plug kit)

So what do you more experienced folks that have either played with these or know the basic theory or practical application behind this possible "innovative" design have to say about these things that seems to be abounding as of late???...Just more "snake oil"???...Any "Myth Busters" here???...lol...TY...DAMIEN

My last motor ran duel plug setup and a guy who built them for a living said something that made alot of sense to me.
Only so much spark is going to produced by the lil magnetos we run so all its really doing is making 2 weaker sparks. Think about it, we don't have enough extra coming out of the magneto to run a 6v light without seriously impacting the bikes performance. Besides if it really was a big difference maker then EVERY race bike in the world would be running them right lol

 

[WEEDHOPPER420]

Welcome to the forums...Your a little late to the party on this thread...I posted what you quoted back on ...Nov 21, 2021, A year and a half ago...lol...Please look for the date codes when replying to old threads...It will help avoid the archeological digs...lol.

I cannot see how you achieve much better spark when your still working off the same basic magneto's supplying electrical power to the dual spark CDI unit...I suspect that the spark would actually be weaker between 2 plugs rather than just one.
(It is the very same "improved", "upgraded", magneto that comes with the regular, stock Zeda 80, single spark plug kit)

I know Damien, i see it now lol my bad

 

[Wyvern]

Obligatory zombie thread reaction.

 

[michael whiteman]

This upgrade is just one more "really cool piece" you can add that will make your friends think you're really cool too.
Does it work? YES but what does it really do? This coil shurely has a plug wire connected to each end of the winding which means, if one plug stops firing the other one will also. Just like in my Tacoma where 2 cylinders share the same coil. All coils are capable of producing more voltage than required to jump the plug gap. Question is max voltage available, which can only be determined by an oscilloscope. This dual plug coil could very well have more turns which would increase the voltage. Bottom line.......coils will only produce the amount of voltage necessary to jump the gap until the upper limit of the coil is reached.

By adding the second plug all you are doing is lighting the fuel mixture at two locations. It stands to reason the two flame fronts will travel across the combustion chamber faster. This is why you see the 100 rpm drop when you are running up your aircraft engine and killing one mag. You have to ask yourself how much faster is my bike because of the second flame front? Compare this answer to the cost, and the fact you'll be buying two plugs. Now, is it worth it ?

 

[loquin]

No matter how closely you set the plug gap, there WILL be one plug with a slightly smaller gap, and THAT will be the plug that usually sparks first. Whichever plug sparks first (and one would usually do so) establishes a conductive plasma path to ground, pulling the lions share of the coil current, and the voltage from the coil drops. In most cases, the second plug never sparks on this cycle.

After time, enough metal would erode from the tighter gapped plug to make them approximately equal, and the second plug gets firing more often.

And occasionally, both plugs may spark close enough together that they both initiate ignition.

The dual plug approach <may> have a slight advantage in reducing misfires, as if one plug doesn't spark, the other one should. There shouldn't be much, if any increased load on the coil, as only when both plugs spark would there be any extra current.

 

[loquin]

This upgrade is just one more "really cool piece" you can add that will make your friends think you're really cool too.
Does it work? YES but what does it really do? This coil shurely has a plug wire connected to each end of the winding which means, if one plug stops firing the other one will also. Just like in my Tacoma where 2 cylinders share the same coil. All coils are capable of producing more voltage than required to jump the plug gap. Question is max voltage available, which can only be determined by an oscilloscope. This dual plug coil could very well have more turns which would increase the voltage. Bottom line.......coils will only produce the amount of voltage necessary to jump the gap until the upper limit of the coil is reached.

By adding the second plug all you are doing is lighting the fuel mixture at two locations. It stands to reason the two flame fronts will travel across the combustion chamber faster. This is why you see the 100 rpm drop when you are running up your aircraft engine and killing one mag. You have to ask yourself how much faster is my bike because of the second flame front? Compare this answer to the cost, and the fact you'll be buying two plugs. Now, is it worth it ?

Well, the two plugs are probably wired in parallel, with two wires running from the 'hot' end of the magneto coil to the two plugs, with the other end of the coil tied to ground. They wouldn't want to wire them in series, as you would need double the voltage to generate the spark, twice.

Now, when a plug sparks, the arc has created a conductive path to ground, and current flows 'downhill,' through the spark. When this happens, the coil resistance comes into play, and the output voltage drops. The amount of drop depends on the coil resistance. One of the plugs will tend to spark before the other. Primarily because they can't be gapped to exactly the same distance. Because the coil voltage drops after the spark is established on one of the plugs before the other, the plug that hasn't sparked (yet) probably won't on this cycle.

As the plugs wear and the gap widens, the other, usually non sparking plug will be sparking more often, and eventually they should both be sparking randomly, about the same amount, each.

The other design approach would be to use a magneto coil with two equal, parallel wound secondary coils. So, redundant coil windings and spark plugs. In this case, both plugs could spark, as the voltages are independent of each other. If a single plug were fouled, the other plug should fire, and the the motor would keep on running. The active combustion could help with burning off whatever fouled the other plug.

 

[michael whiteman]

I'm not sure you understand series plug wiring. If one plug misfires then the second plug "hickups" at the same time. The impulse voltage travels through both wires and plugs at the same moment. Whenever a voltage fluctuation occurs it is seen equally throughout the entire secondary high voltage circuit. Current flow is determined by the resistance in the whole circuit, not one misgapped plug.

A positive senario might be...........if one plug gets bridge gapped the second plug will still fire. I've seen these events you are speaking of on an oscilloscope and they take place in just a few milliseconds. You would not distinguish it at all when riding down the road.

 

[GW's Motorized]

With a single cylinder I don't see why you guys are worried about both plugs going out at once. If you have 1 plug it is the same if your cdi goes bad. I personally think this particular mod has potential to help woth an even burn.