Honda Twins banner

1 - 6 of 6 Posts

·
Registered
Joined
·
234 Posts
Discussion Starter · #1 ·
I want to try a digital tachometer but I see people have had problems. Would a tachometer with one of these settings work?
I guess setting number 3 would work. Does it?

1. pulse per 2 revolutions
2. 1 pulse per revolution
3. 2 pulses per revolution
 

·
Registered
Joined
·
234 Posts
Discussion Starter · #3 · (Edited)
Thanks!
Ok, 1 pulse is what a want but the engine sends a 2 pulse signal?

Anyway, seems like I can choose the right settings on this tachometer to prevent double RPM readings.
 

·
Registered
Joined
·
459 Posts
On your engine both pistons travel in the same direction at the same time. Both arrive at TDC at the same time, one is on it's compression stroke and the other is on it's exhaust stroke but both are at TDC. Your CDI fires 1 spark every time the pistons come to TDC. This engine uses what is commonly referred to as "waste spark" system. What this means is that each time your CDI fires the spark will originate in the coil, travel through the wire to the plug and then across the gap...... BUT WAIT THERE'S MORE..... The spark continues its journey across the other plug gap too.

In short, you CDI actually fires 1 pulse each and every revolution.
 
  • Like
Reactions: Chippe
1 - 6 of 6 Posts
Top