Does the spark plug fire every cycle on the breakerless ignition?

[FatJackDurham 318]

I have been trying to figure something out ever since I discovered I have a breakerless ignition. The manual indicates the coil is fired when a protrusion on the flywheel passes a switch coil, disturbing the magnetic field and causing the spark coil to fire.

 

This would seem to indicate that the spark plug fires every revolution, same as a two stroke, even on the exhaust up stroke. Wouldn't matter if it did, but I am curious if this is the case. A points ignition I assume doesn't have to work about it as it is fired based on a cam that, like the valve cycle, fires only on the compression stroke.

 

Can anyone shed light on this? One of the reasons I am interested is that I saw (foolishly) this website that has fuel injections for small engines... and turbos O.O . I don't know about turbo, but it would be sweet to stick a fuel injection conversion on one of these tractors, just for S&G. But if the EFI use the spark timing to time the squirt, and if the spark fires every rev on breakerless, wouldn't it squirt even on the exhaust cycle?

 

I saw the post where someone had actually put a turbo on a Wheel Horse, but it looked like he had to actual fabricate the whole injection system from scratch.

 

http://www.ecotrons.com/products/small_engine_fuel_injection_turbo_kit/

 

[pfrederi 17,147]

I do not know about fuel injection sensors but yes the breakerless system fires on every rotation so every other spark is wasted on the exhaust stroke.  The KT twins also waste a spark as the coil fires both plugs at the same time so the one cylinder is on the exhaust stroke.

[formariz 11,863]

Good and interesting question that also puzzled me for a while years back.Someone correct me please if I am incorrect but from my experience in trying to make "Tiny Tachs" work with different tractors here, I found that the Kohler breaker-less ignition fires on every revolution since it is driven by the trigger and bump on flywheel, therefor having a "wasted" spark, but the points system one fire on every other revolution since they are driven by the cam..

Edited November 30, 2016 by formariz

[Digger 66 3,476]

Same with the HD single fire ignition system .

 

GOOD QUESTION ! 

[FatJackDurham 318]

45 minutes ago, Digger 66 said:

Same with the HD single fire ignition system .

 

GOOD QUESTION ! 

 

What is an HD system?

 

So, for people trying to make tachs work, a twin cylinder would register as double the RPMs, right?

[Achto 26,573]

13 hours ago, FatJackDurham said:

What is an HD system?

A Harley Davidson ignition. @Digger 66 is close but the dual fire system fires a dead plug, and the pick up is on the cam so while it does fire both plugs at once it does not fire on every revolution. The single fire upgrade for HD only fires each plug when needed, so there is never a plug firing in a dead hole. I've switched to a single fire sys on one of my HD's when I dual plugged the heads on it.

Some of your newer cars with coil packs also fire two different plugs at once.

Edited November 30, 2016 by achto

[Digger 66 3,476]

7 hours ago, achto said:

A Harley Davidson ignition. @Digger 66 is close but the dual fire system fires a dead plug, and the pick up is on the cam so while it does fire both plugs at once it does not fire on every revolution. The single fire upgrade for HD only fires each plug when needed, so there is never a plug firing in a dead hole. I've switched to a single fire sys on one of my HD's when I dual plugged the heads on it.

Some of your newer cars with coil packs also fire two different plus at once.

 

My mistake , I meant to say dual fire .

Sorry folks .

[Achto 26,573]

4 hours ago, Digger 66 said:

My mistake , I meant to say dual fire .

Sorry folks

No worries, I get them mixed up some times too.