If you use a Vincent Power Arc ignition you must use resistor plugs and cables. The Moroso Blue Max 800 ohm cables are provided with the ignition, but are available locally, though maybe not in black. The plug choice is left up to the user due to varying engine requirements. I use NGK BPR5ES and sometimes 6ES. My two coils for single fire are under the cowl on the Rapide, but that is a difficult fabrication test for the average user. I have not had any difficulty with interference, maybe because the ignition uses an optical encoder instead of a magnetic field. I do keep the coil trigger wires away from the plug wires as much as possible. Bob Larmour has designed and uses a mount up on the cylinder head on his Rapide with a dual fire wasted spark coil. I can send a copy of a template if needed. I think it could be combined with the steering damper mount for someone clever. I will be putting the two coils for the TPV dual plug Comet under the tank up by the head, fastened to the Egli type DDV spine tank. The coils are also Power Arc and supplied with the ignition to the users single or dual fire needs and designed to handle the recovery demands of the triple spark capability. You can’t find them at the auto parts store, so I carry a spare (to guarantee I will never need it), and they are only a day or two away by post from me or Power Arc in Iowa. I have not heard of coil failures from the many Norton Commando PA users, but the Vincent users are only a few so far. The people at Power Arc tell me that the main source of coil problems is accidentally hooking up the -12v coil terminal to +12v during installation.
I also use the lifter lever with a complete swing dropping it near the bottom and don’t bother with finding the ideal position first. I have done this since the mid 70’s with magnetos, Lucas distributors, dual points conversions, and with this system. It has always worked best for me since I am not very good at positioning the pistons, especially in front of a crowd that wants to hear a Vincent run.
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