I think you meant paulgp602.

 

Glad you asked, Zorro!

Since the tiny tach picks up its input from only one cylinder's spark plug wire, it shouldn't matter how many cylinders in the engine, seems to me.

Any given cylinder MUST receive a spark pulse for each power stroke; since 4-stroke engines generally receive a "wasted" pulse at the end of the exhaust stroke as well, both 4- and 2-stroke small engines manufactured today usually receive a spark pulse at each revolution. My guess, the Tiny Tach has no idea whether it's working on a single-cylinder engine or anything else, as long as it receives a pulse with each revolution (there are probably models for one pulse every other revolution, as well, for point-and-coil ignition systems).

The guys from Tiny Tach ought to know; think they have a contact (oren@megsinet.net); you can ask 'em.

Diogenes

 

Of course! I meant paulgp602.

If you're reading this, paulgp603, please accept my apology; only a typographical error (numbers are so HARD!) I assure you; in no way did I confuse you with paulgp602.

Diogenes

 

Uhmm, Correct me if I am wrong here.. The "extra" spark would have to happen between the exhaust and intake stroke. With the ignition spark happening between the compression and power stroke. It would seem to me that if you fired these sparks at the same timing on different revolutions then you would have a massive backfire through the carburator. The intake would be open and there would be a live spark sitting there to ignite the fresh fuel/air. I may be being ignorant here, But I have never heard of an extra spark system. And it sounds like a very incorrect theory\idea\what-cha-ma-call-it.

 

AdrenalinFreak, why not examine the ignition system on your own ATV.

Is there a magnetic pickup connected to your CDI, mounted near your alternator rotor?

Does the alternator rotor have a projection that rotates near the magnetic pickup?

Or does your ATV have ignition contact points making and breaking electrical contact with the primary circuit of an ignition coil?

If these answers are "Yes," "Yes," and "No," your ATV probably has a "wasted spark" ignition system, firing every engine revolution, no matter how strange the concept. The projection on the rotor passes the magnetic pickup each revolution, consequently triggering a spark.

If your answers are, "No," "No," and "Yes," then you probably have an ignition system that fires once every two engine revolutions.

The "wasted spark" system is much simpler and more economical to manufacture (no point cam drive, no points to adjust/replace, no capacitor to replace, no timing/dwell adjustments necessary with age/service life). Some even say the extra spark helps reduce emissions, burning mixture more thoroughly; however, this contribution to a cleaner environment would appear a small one to me.

Diogenes