Spedo and Tach ratios

[aeromech]

I am currently in the middle of a 1980 CB750F SuperSport Cafe/Brat project and I am wanting to buy new gauges like the ones that dime city has for sale, does anyone know the correct ratios for the Speedo and the Tach. I am planning on using stock tire height.

 

[Steveo]

I am doing the same thing, same bike and would also like to know haha.