CBR F3 Speedo jumps 0 - 20 mph when ignition OFF to ON

Street speedometer on F3 goes from zero to 20 mph when turning ignition on. Bike isn't even running yet. When riding, the speedo has an approx. 20 - 30 mph offset higher than the actual speed. Not sure how it affects odometer. I'm downloading the wiring diagram now. My F2 was a mechanicla speedo. Pretty sure F3 is electronic. Any ideas?

 

The speedo is picked up off the transission. I believe it's the piece mounted in the top case by the starter. I don't have a speedo on my race bike. You will have to pull the tank, airbox and carbs to get to it.

 

I found a wiring dgm late the other night and glanced over it. That must be the 'speed sensor' that's on the transmission. I'll have more time to look into this weekend with the multimeter. The temp guage isn't working either. I was hoping this may have been encountered before and was an easy fix.

 

The temp picks up off the thermostat housing. If it's still hooked up then the guage is probably bad.

I'm putting one of these on mine so I don't have to worry about all that stuff going bad
http://trailtech.net/motorcycle_vapor_kits.html

I would add one of these for a streetbike
http://www.trailtech.net/motorcycle_indicator_dashboards.html

For around $175 you get all set up.