93 Spider Veloce Speedo & Tires

["Robert J. Favali" <rfavali@domain.elided>]

Friends,
My 93 Spider Veloce registers around 13 MPH on the speedo
when at an idle.
Once you pass this speed, it is correct -- or at least it
registers a speed greater than 13 mph!
Why? How to fix? Electrical? Mechanical?

Also ... wanting to replace the tires. I have Pirelli
195/60-15 and am considering going to Pirelli P-6000's.
Thoughts? Better tire than the P6000 for non-race, summer
only, hard driving?

Thanks!
Rob Favali
Connecticut

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