Jumping Tacho !
 

My 998 Tacho is starting to jump around , i have checked & cleaned the Battery terminals & it is still the same any ideas ?

stop using the throttle so erratically? .:lol:

sorry i'll get my coat.

My 916 used to do it regularly on track days, was loose connection for the tacho pickup.

Sounds like it could be a sign that the battery is dying as it's not charging.
Check:
- 14V across terminals at 3Krpm (if yes then the regulator is OK)
- Yellow leads from generator where they pass behind the battery box (these are not of correct capacity for the output and have a tendency to melt and then short out leading to no charge to battery)

Erratic Tach
 

Most likely - Intermittent power or earth connection
Next likely - Intermittent rpm signal connection
Least likely - Tachometer internal problems

So first check for a loose or corroded electrical connection at the battery, the fuse, and any in-line connector. Check the two battery connections first, next the connector at the instrument cluster, then at the fuse, and lastly at the wiring harness connections.

Next, since the bike is running OK, the RPM sensor gap, the sensor itself, and wiring back to the computer are not the problem. So you need to check the connectors between the computer and the tach.

Finally, try to borrow a tach to verify that it’s actually the problem, before buying a replacement.

Thanks so far , that's something to go on for now .
The bike is only 16 months old but i would like to try & fix it myself before taking it to the dealer
If if looks like the Tacho then of to the dealer it goes !

Fairings of & all (that i could find) connections checked & cleanned also getting 14volts across terminals when at rev's
So will phone dealer in morning & book it in , seems like a good opportunity to get the 999 Demo bike at the same time !!!