Hello Mike:
Re starters: I have used both a friction starter and a starter/generator on my 6/1. The friction starter is made with an automotive starter motor and a fricrion wheel. The friction starter works fine moast of the time, and is very simple and inexpensive. The only problem with it was that my flywheel gets wet and sometimes iced up with freezing fog.........not enough friction. I have installed a golf cart starter generator to eliminate the lack of friction in those freezing for situations. Since we have not had the fog as yet this winter, I cannot say how the starter/generator will perform under those conditions.
Friction starter has the advantages of inexpensive and easy to fabricate. There is no load on the engine when the starter is disengaged.The starting battery is topped up by an electronic battery charger.
Starter/generator works with the flick of a switch, recharges its own battery, is a lot more costly. The drive belt is always engaged, so there is a bit of extra drag, though seems to make no noticeable difference in performance.
I am currently using the starter/generator set-up. but the friction starter just needs to be hooked up to a battery and it is ready for action.
An air driven friction starter works fine, especially if you hav an aircompressor belted up to your engine. I don't. We have seen friction air starters working well with either a tire or a much smaller friction wheel as on my modified automobile starter
They are both still installed, you can see photos at this link
http://listerengine.com/smf/index.php?topic=7715.msg87441#msg87441Cheers,
Hugh