[Kenneth_Moore]

"A 270-degree firing interval essentially turns the motor into a 0-degree V-Twin"

I guess I should have read the homework assignment Mr. Duke, but I don't understand what you mean. Can you elaborate on this?

 

[Kenneth_Moore]

It means they staggered the firing order to simulate a V-Twin firing sequence without the cylinder arrangement. The traditional Triumphs had 360-degree firing order. One cylinder fired every revolution. It had a very even exhaust sound. The 270 gives is a bit of 'potato-potato' sound.

So they make a point of not building a V-Twin, and then build the inline twin to sound like one. Schizophrenic. It will never sound like a Shovelhead, so why even bother?

 

[Kenneth_Moore]

One more explanation and I will be completely lost. Wait, I already am.

 

[Kenneth_Moore]

Here it is Ken. Normal Vertical Twin motors have an even firing sequence of once every 360 degrees of crank rotation. Every time the crank goes around one cylinder fires and the next time it goes around the other cylinder fires. One cylinder fires at the 0 position for every 360 degrees rotation. If it was a clock, pistons fire alternately at the 12 oclock position

Now, what triumph did here is to stagger the firing sequence to fire at 270 degrees of crank rotation, which means that it will fire at the 0 position and then again at 270 degrees of crank rotation instead of going all the way to back to the 0 position after 360 degrees of crank rotation. If it was a clock one would fire at the 12 oclock position and the other would fire at around 10 oclock.

How's that?

Ok, I get it. And I think that explains why they need 2 balance shafts and a third vibration damper. They've designed in vibration in their pursuit of a sound. You might say they "Runed" a perfectly good motor.

 

[Kenneth_Moore]

Wow, a calm voice of reason! What are you doing on this board?!!

Ain't he great? The man is ON FIRE!!!