I am working on installing the correct zr4 mag on my 30, the mag that was on it (a newer bosch with a inpulse) was "directly conected" meaning no timing adjustments. I am looking for a pic of the correct drive pieces and a procedure for timing it.

Thanks for any help

Steve

What you have in pic is exactly as the book shows for PS0001 - PS2932 if you need i can send you pic but what you got is what it shows

Ok, thats a good start since I have the stuff I need except for a easy to get roll pin.

as far as timing, would it be correct that it makes no difference on timing as long as the wires are in the right order and start with the compression stroke TDC cylinder on the hot post?

It may work ok just to hook it up but I would think you should be very carefull because the impulse varies some from mag to mag and will greatly change the timing. Hook it up and slooowly turn the engine over and see if it fires right at or just very slightly ahead of top dead center. If not better adjust, may even have to driill a new hole.(or just use a set screw temporarily) Most of the thirties seem to have an adjustable link with two machine screws in it so fine tuning is possible.

Steve, is there a lever coming out of the front of your mag that can move the cam that opens the points. Many old mags like tha have them (IHC E4A and aero splitdorf). T time them you put a piece of ciggaret paper in the points and whenit lets go of the paper it fires. You will need to go over tdc and back up to get the impulse out of the picture. If you have a timing advanc lever I would look for timing at TDC fully retarded.
Later Bob

The hole should be ok just bolt it all together when you time it make sure plugs are out or wires off, but before you try to start be sure to trip the impluse and if it flutters and trys to start be sure you re trip or you wont be crankin nothin for awhile

Ok

a new development, I have 2 different drives that fit on the mags taperd/keyed shaft and they are indexed different, I will procede with caution. I broke my wrist on a rd6 and learned a lot of respect for crank start engines,
I was aware of how easy the trip lever will unlock on this type of mag

also the disk between the 2 drives is made of steel, most of the ones I see are made of a brown fiber materal, I was thinking I would make one out of nylon, if I find the timing is off a few degrees O could adjust it with a custom coupler disk