I posted a topic on this last month, I started having problems with the tach freezing or not working at all, then all of a sudden it would work again then quit. I took it to the dealer and they replaced the tach. Got the bike back went on a trip with friends and the tach as still not working, it actually was worse. This has to be a wiring problem. I am starting to get a little upset with my dealer. Why didn't then check the wiring? My dealer is 65 miles away one way, and it is costing me a bundle of money for gas (1978 ford F-150). I have to take it back now and they tell me they are back up about 10 days and they will get to it when they can. This will be the third time taking the bike down to the dealer for this problem. I would appreciate if anyone has had this problem to let me know so I can give the dealer's mechanics some "advice" on the possible cause. Thanks guys!

 

I used to have a similar problem with my ski boat. Turned out to be a ground issue. I would check to make sure that the wires are grounded good. More often than not the problems are simple Loose connection, worn insulation, bad connector, that kind of stuff.