First the bike is running great. But here is my puzzle. I got one of those mini tachs for Christmas and after reading several of articles on the mini tachs I assumed it was a 2:1 ration and I would need a single fire adapter since my 2005 FLSTC is single fire ignition. So being basically cheap, and also part of the enjoyment of a motorcycle is doing things for yourself, I read an internet article on how to build a single fire adapter from parts purchased very cheaply at Radio Shack. So I wired up it all up and started the bike and the tach read zero. No problem I thought and rewired it without the adapter and sure enough at idle it read 500 rpms and I know my idle speed is 1000 to 1100. Since I can do the math (at least I can multiply by 2) I thought this is cool and will order a “real” single fire adapter from Barron’s. But first it was time for a ride. Well a few miles down the road the rpm read out doubled and by all my calculations was reading the engine speed correctly. Now sometimes it reads at ½ the rpms at start up and in a mile or so starts reading rpms correctly. Sometimes it is correct from the get go. Do you think there is some circuitry in there that can tell what single it is getting? Not a major deal but I am curious as to what the wisdom of the forum has to say. Thanks.