Motorcycle Repair: fzr 600 tach doesnt work, car battery, voltage regulator

Question
Hey Falcon thanks for your help!
my battery was dead i jumped it to fire it up. i noticed my tach didn't work. i took all elec connections apart and sprayed them with elec. connection cleaner and coated with elec grease cause i stored it outside in winter without a cover. when i last put it away the tach worked just fine however my voltage regulator went bad and the bike stoped running on me as a result. i did replace it though and the battery as well. i read that if you jump a bike at least mine you run a risk of messing something up that would cause the tach to not work. basically in my chilton repair book there is nothing that covers this problem nor any trouble shooting. Do you have any ideas or tests i can do?

Answer
Hi Jason.

I have no info on tests that can be done on the tach itself, but I can tell you this about jump-starting from a car;

It can be done safely on any bike AS LONG AS THE CAR IS TURNED OFF.  Jumping it like normal (battery connected to battery) and using ONLY the power available from the car battery, it should be no issue at all.  I have jumped quite a few bikes in this manner without any problems.

For the tach, before you trash it, check the wiring for shorts  in the circuit for the tach and see if you have any there.  Also check your fuses.  The tach is tied in to one of them, perhaps instruments or signals.

Good luck and ride safe.
FALCON