Datsun Roadster Forum-311s.org

I have a 66 roadster that I just purchased and the speedometer will not exceed 45 mph. It seems accurate up to that point but just maxes out. Any ideas?

Bigger engine probably need to get inside the unit to find the problem. They can be rebuilt or you could probably find a used one for a reasonable price.

Honest Officer, I am not saying that your radar is wrong, but my speedo only said 45mph....

I had a 720 that had the same problem, but with the tachometer.
Upon disassembly, found that the drum had small spots of rust on it. The clearances were so tight that that tiny bit of rust would prevent the needle from going past 3000 rpm. Some very careful scraping with a small pick remedied the problem.

The drum on the 65/66 and 67 speedo's and tach's tend to gradually slip on the shaft which doesn't change the calibration but ends up moving the stop to random locations. Unfortunately you will need to tear it apart to relocate it and secure it in place.

Jon