I have a Honda V Twin 18 hp that was not firing on one cylinder, so I put a new coil on it, and now neither of them are firing. I have ohmed all three coils and they are all the same. I also put my ohm meter on it and spun it over and they seem to be building fire but no spark. Any suggestions?

Hi,
The engine depends on a baterry-energized ignition. It has a control module that is used for this also located at the lower left rear of the engine block. Both the module and the coils must be supplied with 12 V battery voltage. That is the first place to start; checking for voltage. The module usually has connectors that are turned so that they cannot be plugged together wrong.
The module can be sensitive to pressure washing and water, as can be the connectors. First thing I do in the case of a Honda with this type if problem is to unplug and re-connect all connectors to make sure they have good connections. It solves nearly 90% of the problems. Do the same with the key switch. Check for voltage and most of the time everything worke again. Let me know.
Peace,
Clarke