Cheers

The speedo reads in mph and was working fine for the first four months I had my bongo. Was a gradual thing, first flickering slightly up and down, then large fluctuations and then not working at all for long periods.

Thanks to all who responded. Would thank you individually if I knew how.
Spoke to John (francophile) at Kings Lynn and he had a look at my speedo. Apparently it is a chipped speedo with dial going up to 180 (km/h). John suggested a 626 speedo replacement but I have noticed on ebay "delimiter chips" for £20. Could I not just replace that part?
Cheers
Dave