[basket case king]

bought a dayna dual fire ignition for my 1975 shovelhead the question i have is what should the plugs be gapped at also someone said i should have a different coil what should the coil resistance be and how can i check it?

[Killer-B]

Hi there, well, you did'nt give much info to go on, I'll assume you bought it used, as if you bought it new you would have all the instructions to install. Yes, you will have to get a coil that will work with that system, probably 3 ohms.
GAP
1966 - 1969 0.025 - 0. 030 in. ( 0.63 - 0.76 mm )
1970 - early 1978 0.028 - 0. 033 in. ( 0.71 - 0.84 mm )
Late 1978 - on 0.038 - 0. 043 in. ( 0.96 - 1.09 mm )

Good luck

[CD]

Originally Posted by Killer-B

Hi there, well, you did'nt give much info to go on, I'll assume you bought it used, as if you bought it new you would have all the instructions to install. Yes, you will have to get a coil that will work with that system, probably 3 ohms.
GAP
1966 - 1969 0.025 - 0. 030 in. ( 0.63 - 0.76 mm )
1970 - early 1978 0.028 - 0. 033 in. ( 0.71 - 0.84 mm )
Late 1978 - on 0.038 - 0. 043 in. ( 0.96 - 1.09 mm )

Good luck

Whew!!! So true! Dyna S? 5 ohm same as points Dyna electronic? 3 ohm and gap same as any electronic.
Select option C from KB's list above.