Dyna 2000 on GXSR1100 - tacho/wiring help?

[wraith]

Hi all,
Just got (off the missis's bike) a Dyna 2000 'black box', and put it on the GSXF (1127cc) Kat. The thing is, I can't get the tacho working (missis never ran it with a tacho). I'm using the standard Kat clocks and the tacho worked with the standard black box before I swapped them over (a month or so ago, anyway).
I've rung Dyna to check that I've wired it up right and I have, and we've checked Haynes manual wiring diagrams and Dyna's instruction and advice leaflet, but still no joy.
I've tried connecting a separate tacho which I think works to the green Dyna wire with a live feed and an earth from the existing clock harness and it doesn't work.

The loom's off a GSXR 750/1100, I think 85-87 UK according to the manual. It has a black with yellow tracer wire from the original black box to one coil and to tacho, as opposed to a black with red tracer which other looms have (and not all go via or get a signal from the coil).
I've tried connecting the green (or yellow) tacho output wire from the Dyna box into the black/yellow wire into the clocks (which seems to be the tacho feed from the original loom as far as I can tell, no other spare wires for it to be) and nothing works (the black/yellow is otherwise disconnected from everyting else now that the Dyna's fitted, of course).

So:
1. Has anybody had this problem and how did you get round it?
2. Is there a way of checking the green wire (from Dyna box) is working/giving a signal? (Or yellow wire - neither is working in tacho terms.)
3. Will the rev limiter still work with the tacho lead not being connected? (bit loathe to try without a rev counter!)
4. Will it be OK to take a wire from the coil to the tacho with out fu*king the Dyna box? (i.e. taking a tacho signal direct from the coil and not the ignition box, by passing the box altogether?) If so, will it read right or half or twice (don't know what the original black box output 'speed' was, though it does seem from the wiring diagram that the original tacho wire just takes a signal; from one coil)?

Cheers.

Edited December 7, 2015 by wraith

[Ben Slabby]

Yeah, rev limiter will work fine. If you're having issues, just pick up a tach signal from one of the coils, it'll work and not harm the Dyna. 

Ifyou're bothered, I'd try a substitute rev counter just to see if yours is iffy.  

[wraith]

Nice one, thanks