Gage ratios?

I am planning to change gages on my '79 KZ1000. Can someone tell me the ratios of both the speedo and tach? There are some aftermarket ones on ebay with various ratios so I want to get the right ones.

The speedometer is probably a 2240 --- it may have 2240 revs = 1 mile stamped in ink on the back of it. Aftermarket units are typically listed as 2240@60mph or something like that. I think the 2240 stuff is a Japanese standard.
I don't know about the tachometer.

On the back of the KZ 1000 is stamped in red ink R = 1 : 5
Steve

Thanks very much for the info, That should get me the right aftermarket gages. I will let the forum know how this worked out.