Speedo readings

I recently checked my speedo readings. At 30mph I’m doing 23 mph according to my speedo and at 40 mph I’m doing 30mph on my speedo. Any ideas?

Yes 1993 Vespa px200e, with the original speedo.how do I make it read correctly.

I would say that you must be riding a vespa… and I’d even bet that you have a Veglia speedo [:D] …they’re good like that [;)]

Try changing the speedo drive in the front hub. If that does not fix it get a new speedo.