I'm pretty sure I already know the answer to this but thought I'd ask anyway.
Is there anyway to adjust the accuracy of the tach on the f3? I have a '98 that has extremely low miles but for some reason, the tach is off by about 300 rpm. I have an Actron bench tach, which I have verified its accuracy against other tach's, so I feel confident that it is correct. When I adjust my idle to 1,200 on the Actron, the bike reads 1,500.
I don't know of a way to adjust it or if there is a part other than the tach itself that can be replaced or tweaked. I can live with it as it is, but my OCD mind will always know it's not right. Any advice is appreciated.

 

Aftermarket Tach?????

I'm not sure there is a way to adjust it.

EDIT: How does the tach get its signal on the F3? Is it from the coil? Or is it off of a rotor?

 

It's the OEM tach that came from the factory.
The only thing I've found in the HSM so far is measuring voltages to determine if it's a bad tach or ICM. I'm sure the info is in there somewhere, I just haven't found it yet.