Any Experience with Koso Gauges?

I have the Koso T&T Multi Gauge and overall I'm very happy with it. Seems well made and all the info i need is in one compact spot. But I'm having an issue with the tach bouncing around some. It's currently hooked to the ring terminal on one of the Dyna coils. I'm curious if hooking to both would help any?

Pics?
Steve

Horrible picture but it's the only thing I had on my phone. Had snapped a few quick pictures before I dropped it off to have some carb adjustments made.

I used a Koso on an ST 1300 fighter nine years ago, high quality and easy to install. Check your ground wire.

I tied the ground into black/yellow in the headlight bucket where my other connections are. I'll try grounding straight to frame and see how it does. Hope to get my bike back this weekend. Thanks

The ground circuit is always marginal on our classic bikes. I always build my own. 12 guage wire and directly back to the ground point of the battery. I then feed all of the major grounds back through it. The headlight, horn, taillight and ignition. Everything works better.

Yeah I've been going through the wiring redoing things here and there just to clean it up and get it more reliable for the summer. I plan on redoing it all this winter so I'll end up doing something along those lines. Really want to lean it up and switch to deutsch connectors for simplicity sake. Appreciate the input. I'll definitely redo the ground to see how it acts.