Topic: It's 2010! Time for more questions - replacement tach and speedo

[ev0lve]

So I've got some plans to swap out my 750K frontend for a GL1000 this year and I'm ruminating on what I'd like to do with the gauges.

Poking around, Mike's XS has some pretty handsome stuff but it occurs to me I know exactly nothing about whether they would be accurate or not or how to begin figuring it out.

CB front rim is a 19, GL front rim is a 19, seems an XS front rim is 19
Here's the spec Mike's gives

Black Face 0-130 MPH with Tripmeter.
LED internal illumination. Mechanical cable drive type
(60MPH=2,240 RPM)

I'm guessing I'd need to measure the tire around, figure out how many times it takes to make a mile and then multiply that by 60 to get the RPM but hopefully someone just knows this number off the top of their head?

And on the tach

Black face. 0-10,000 RPM with redline
mark at 7,500 RPM. LED internal illumination, Mechanical
cable drive type (1:5 ratio)

I haven't run across the ratio anywhere for reference. Would it be accurate?

Thanks!

Kind of what I'm thinking of

And this fellow had a very nice piece made up

Edit: This is Bonafide's machine.
http://forums.sohc4.net/index.php?topic=30793.msg356533#msg356533

[Bodi]

Yamaha uses 1:5 tach ratio. Honda over 500cc is 1:4.

[ev0lve]

The Mike's XS gauges are prettier but CycleX has a CB specific pair
http://www.cyclexchange.net/Honda%20Cafe%20Page.htm - about a 1/4 of the way down the page