1. remove the rear handlebar cover including the speedo.
2. Dismount the gauge panel from the cover.
3. Remove the "lens" from the G. panel
4. Pull out the small stopper pin for the speedo needle
5. Pull of the silvery cover from the needle
6. Now the needle will go down to were the spring force is zero
7. Note at which reading the needle stops.
8. Pull the needle gently of the shaft with your fingers, this feels rather scary at first. The shaft for the needle is very thin.
9. If the needle stopped at, let's say, 5 km/h and your error is 10% then you should put back the needle on the shaft at "-5 km/h"
10. Turn the needle a bit and put back the stopper pin
11. Assemble everything back on the bike in the reverse order
12. Go for a ride and enjoy your new-found accurate speedo.
PS. This would probably work on a Vespa too
⚠️ Last edited by jk_single on Wed, 23 Sep 2009 19:06:13 +0000; edited 1 time