Thanks for the reply PackRat. I used a universal 12v coil that I mounted under my springer seat with a chrome cover/bracket. I wired the + to a momentary switch and then to the battery, and the - to the spark unit that triggers the rear coil. When I push the button it reduces the spark for the rear cylinder also so that helps put more gas in the exhaust. I got some plug wire that goes to the plug in the front pipe, and then I spliced into it there and ran it back to the rear pipe. The plugs I used were for a chain saw/weed eater and are only 1 7/8" total length. Pretty simple setup, but it works. I've been running cheap ways to do propane through my head and I may tackle that one day soon. Tough to find places to hide the bottle and valve. I could use a solenoid valve, but they are very expensive and I don't got the bread for that. Thought about kiping some hoses from a gas grill and using one of the valves from it, but it'd be tough to find a place to hide/mount it that would be accessible while riding. Any ideas for valves? I don't know how much pressure some copper tubing with a small ball valve could take?