The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => A7 1946-1950 => Topic started by: Craig on 26.07. 2016 05:43

Title: Longstroke Timinig - Useful info
Post by: Craig on 26.07. 2016 05:43

I know there are lot of threads on this subject already - but thought I would share this info as may benefit some people.

If you are not using timing wheel / disc for whatever reason - here is handy tool to calculate Piston Travel in mm vs Crank Rotation in degrees

http://www.dansmc.com/mc_software2.htm

Taking standard Longstroke measurements:
Stroke 82mm
Conrod length of 6.5" (165.1mm)
Standard Timing of 5/16" would be approx. 32.7 deg

That gives a piston travel in mm of 7.897mm for 32.5 deg (I used 0.5 degree increments in the calculator)

Title: Re: Longstroke Timinig - Useful info
Post by: muskrat on 27.07. 2016 11:03

G'day Craig.
I've used that page a fair bit. Check out some of his other pages. I like this on his carburetor page.
"Now we come to carburetors. FIRST go get a working fire extinguisher and put it in easy reach. Trust me... if you work on carbs and engines long enough you will light yourself, or an engine, off sooner or later.
Cheers