Tacho/Rev counter drive ratios

[cagimaha]

At the moment I've got a cable driven (as opposed to electronic) tacho from an early mito on my mito 350 after being informed that they are the same drive ratio as the 350LC motor. I am now coming to believe that this is not the case and that mito tacho under-reads... Which isnt the best of ideas. What I want to know is if a cable driven clock from a TZR125 will have the same drive ratio as a 350LC? Or if not does anyone know of a tacho with the same drive ratio that is roughly the same size and dosent have any idiot lights or other gauges on the face? Cheers, Ben.