Sip digital speedo Again!!

[al pushpak]

Hi, been messing about the best part of the day with it trying to find tune the speed setting using a gps sat nav, it seems fine up to 40mph with regards to the gps , but once I reach about 50/60mph on the gps the speedo is 10 mph slower! ( at 50mph gps the speedo reads 40mph & at 60mph gps the speedo reads 50mph) I've messed about with the tyre circumference settings which I measured at 1300 mm & was the setting I started with but it makes no difference if I lower or higher this setting! the gear ratio is set 0.77 & the rpm setting is 3 & it runs a standard speedo cable not a magnetic pick up. any help much appreciated! that's in advance. Cheers

[bennn]

Think you need the gear ratio at 1 for Lambretta, I beleive (may be wrong here) you only mess about with that on Vespas.

Ben.

[Fast n Furious]

TBH. it sounds like you have a problem with the speedo drive or cable for it to be giving you readings like this. ?????/