dunstall

Hi, does anyone no where to find information about the Norton dunstall engine 810. What are the differences between the 750 and 850 commandos. Does the dunstall have a different crank. Are the rotor on 750 and 850 interchangeable does the 810 have a different rotor and timing mark as compared to the 750 and 850.I have been told I have a dunstall engine however I have yet to prove this.I have an 850 and 750 commando a british parts supplier told me the 850 and 750 rotor are same yet the 850 rotor I have will not fit the 750. So of course I am wondering if the 750 crank having the larger crank shaft and this is preventing the 850 rotor to fit is the 810 dunstall crank anyone?

dunstal

the dunstal 810 is a 750 bottem end with an aluminum overbored cylinder. the nuts that hold the cyl. on are diffrent than the750 ones as are the cam followers. the easy id is the top fins on the cyl do not match the bottom fins on the head like the 750 cyl. the 850 does not have the outer 2 nuts on both sides of the cyl. like the 750 or 810.
I guess you are talking about the alternator rotor because of the timing marks. as far as I know thy should all be the same.

bill