Odometer slightly fast.

[PropTP]

I recently bought a used 2001 TT600R Belgarda with 10500 km on the clock.

I've noticed that the speedometer shows a reading that's around 7-9 km too fast compared to my GPS. That's no problem, as I know that almost all vehicles speedometers do that, incl. my 2001 Mitsubishi Colt. Something to do with EU allowing a reading that's too fast, but not the opposite.

Problem is that my odometer is running too fast too. On a 80 km ride yesterday, where both GPS and odometer was synced at the start, there was a end.difference of around 1,3 km.

The good thing about it, is that my bike has actually done a good deal lesser mileage than the clock says.

The bad is, that it's racking up the miles too fast and true fuel consumption is actually less than I thought it was.

My questions...

1. The speedometer and odometer are connected and reading from the same input, correct? So one cannot fix one independently of the other?

2. My speedometer needle jumps up and down slightly when riding. Is that a sign of something wrong? Nothing crazy, but definitely not steady. (I'll see if I can get a video up)

3. Is there any easy way of calibrating the speedometer/odometer, or should I just live with it?

I'm running 90-90/21 Heidenauer K60s on the OEM rim.

Thanks,