Any ideas if this would work on a zx12r?

Digital Gear Indicator for Motorbikes - Universal | eBay UK

Looking at it, it seems to require a seperate signal for each gear on the box. Normaly the box only has an output for neutral, so where the signal for the other gears would come from I havnt a clue. I have seen these units before and were about 70 quid and I believe they come with an electronic box that drives the display. That's my 2 pennys.

Dan

what about combined with this
http://www.angelfire.com/wa3/r.miklos/shiftindicator/gearindicator.htm

In theory, yes, in practice I don't know if you've got all you need in the 'item' description.

Devices such as this are programmable, it simply looks at the wheel rpm and the engine rpm - it's progammed to then give you what gear you're in by looking at the figures. This (apparently) just hooks into the speedo/ECU/whatever feeds from the existing sensors?

Some use independent sensors Hall magnets on th eprop/wheel/whatever for the speed, and a simple tacho feed from anywhere else suitable. These devices would certainly work and are what you need for such certaincy.

Modern bike engines *do* know what gear they're in, or at least the ECU does. They have different ignition/fuel/traction control maps (and a lot more) for each gear.

Some are simple resisitive drums on the gearchange (GSXR) so that you have a different ohm value for each gear. You can use this directly on an independent display.... simples.....