Norton dual points

[Monkeypants]

Bob Dunn says get all of the advance in early with a Vincent. Bob gave advice on the Pazon advance slope (can't really call it a curve) for Vincent engines. I recall it starts with about 4 degrees advance for kick starting, slopes steeply up to 15 or 20 for idle, then is all in at 31-38 degrees(depending on two plug or single) by about 2,000 rpm.
No complex curve thru the rev range, Bob says they like the straightforward and all in early approach.

Glen

 

[Oldhaven]

Bob Dunn says get all of the advance in early with a Vincent. Bob gave advice on the Pazon advance slope (can't really call it a curve) for Vincent engines. I recall it starts with about 4 degrees advance for kick starting, slopes steeply up to 15 or 20 for idle, then is all in at 31-38 degrees(depending on two plug or single) by about 2,000 rpm.
No complex curve thru the rev range, Bob says they like the straightforward and all in early approach.

Glen

Thanks Glen, I will be changing out the advance springs for the softer commando ones tomorrow. I think the idle is too retarded, due to the stiff advance springs, plus I have to tune in the cylinder spacing. I can see the advantages of this rather complex ignition set up, once it is right, though the magneto is a great and simple way to go if you have a good one. Getting there.
Ron

 

[litnman]

Has anyone else here used the Dyna S DS6-2 Single Fire ignition? It's made for 45º Harleys but one module can be rotated to 50º. I'm not
using auto advance so had to make a manual advance. Sounds good on paper but haven't tested it yet.

 

[greg brillus]

We have installed a few of the Crane/S&S Hi 4 and Hi 4N type ignitions which work well and are quite adjustable. The old ones had an adjustment to alter the firing point for the rear cylinder on Harley's plus or minus 5 degrees, which made allowances for our 50 degrees, but the new ones don't have that feature any more. So we modify the rotor by adding a small amount to one of the gaps in the rotor to change the timing from 45 to 50 degrees. Takes a few goes but you can set it up dead accurate, as it has a small red LED light that tells you the instant the coil will fire. It has adjustable advance curves, and a retard setting for starting to avoid kick backs and a few other good features. I think they would be very reliable......Cheers......Greg.

 

[Oldhaven]

I saved this document from 1999 written by Geoff Collins describing how to modify Boyer Bransden ignitions for non standard offset cranks. It could be used on a 50 degree twin. I imagine the same process would work with some other systems as is mentioned above. I think John Healy also wrote something about modified vertical twin crank configurations and the ignition mods required.

 

[Oldhaven]

I also found a later article by Geoff that proposes a less expensive method that requires just one black box and kit, and in my case I suppose the Boyer Commando kit would work. Halfway down the page he describes this in a general way. One pickup pin on the stator is cut off to remove the 180 degree waste spark and one magnet on the rotor is moved. I am not sure how this would work with the printed circuit board on the back of the stator and the individual wires to the coil, so I will trust that this has been done successfully. This would not have the individual adjustability of the original Norton 10CA points, and would have to done very accurately, but would be no different than the ground KVF ring cam in that sense.

http://victorylibrary.com/brit/offset-c.htm
http://www.ebay.com/itm/Genuine-Boy...ystem-12V-Norton-Atlas-Commando-/351055635354

I also note in the Boyer Bransden products website that the recommended and provided wires are copper core, but they call for suppressed plug caps since the interference messes with the computer chip in some of their systems causing starting problems and erratic running, and may even destroy the electronics. Sound familiar?

Ron

 

[Bill Thomas]

It's funny how talking to like minded people can help you later, My brother Ron and me were finishing off his rebuild of a Comet , For a friend, And we found we had a Mag' that went the wrong way, He lives 3 hours away from me so I didn't have all my stuff. It had a Bright Spark mod' on it , So Ron rang him for advice, He is a top Man !!. I thought it would need to be rewound, But Bill ,"Bright Spark", Said if we take the cam out and grind the location notch in a special place and reverse the points like you can do on some of them, We might get away with it. To cut a long story short, I had to eat my words to Ian on this thread about running the points the wrong way !!, I put a lead in on the fibre points heel and ran it the wrong way !!, Who cares, As long as it goes !!.
The Owner who lives near London, 5 hours away !!, Can sort out another Mag' Later. We all have to get the info' that is out there and use it as best we can. Many Thanks Bill.