Re: long bang forble tricycle cub done

Fri Sep 07, 2012 10:45 pm

Landreo wrote:To run as a "forble" I needed to add a second set of points 90 degrees from the original, I used a set of lawnmower points to get the 90 degree offset.
Major cam shaft modification would be required. No changes made to crankshaft.

Ignition firing, firing order would be: Fire the two cylinders at TDC compression stroke. Fire other two cylinders at 180 degree crankshaft rotation. 540 degree crankshaft rotation without firing cylinders or firing the cylinders on the exhaust stroke. Bringing us back to fire two cylinders at TDC.

Re: long bang forble tricycle cub done

Sat Sep 08, 2012 5:53 am

So the version with modified crankshaft would fire evenly, like a Deere, while the modified camshaft would "lope", like a Harley. Two different characteristics and sounds, but two different ways to make it a twin cylinder.....