firing sequences on parralell twins

There'd probably be a slight rocking couple (if I have the terminology
right) side to side, from the force being applied alternately on one
side of the engine then the other. I'm guessing you'd probably only feel
it at higher revs.

I actually thought the early Trumpy motors felt like a single revving at
double the revs to actual but I'm obviously not as sensitive to nuance
as you must be.

JL
(insensitive bastard that I am)

 

....and you meant 90 degree 'L' twin!

 

My Triumph T140 was strongly modded, joe hunt magneto, high lift cam,
40mm amals etc etc etc.

For a trumpy parallel twin it was a revver... that may be why I could tell.


G-S

 

It is.

Generally the cams are set up to fire the cylinders alternately, so
yeah, the pistons go up and down together but one is on the compression
stroke while the other is on the exhaust stroke, if you see what I mean.

Boxer twins are kind of like this too. The crank pins are at 180
degrees, but then so are the cylinders ...

Yeah, pretty much. Offset-crank V-twins are cool too!

-----sharks

 

Methican bandith?

Postman Pat