2 Strokes Down Under

I have fitted a motogadget mini digital speedo to my bike because i have the R6 front end.

I have connected the speed sensor to the back wheel.
I have NOT connected the tacho function wire as it is not needed
I have connected the power to a switched positve and connected the earth.

While your riding the speedo works fine up till the tacho reaches 5500rpm then it goes haywire with speed readings of, for example 484,358,433 klms per hour, drop back below 5500rpm its works fine.
If you sit with the bike in neutral and rev it above 5500rpm it does the same thing, then when it drops below 5500rpm it reads zero as it should .

It seems that there is some sort of electrical interference at high RPM.
I have insulated all the wires properly.
It is installed as the instructions advise.

I have contacted motogadget but they were no help. I thought at $300 for the unit there would be some sort of after sales service but no.

Can any of you electonic guru's help me???

Hmmmm thats a good one.


How are you earthing the tacho? to the frame or directly to the battery?

What happens if you power the tacho separately? ie: connect it to its own 12V power source. Does it remove the disturbance?

Maybe you were doing 484 Million kmph

Definitely interference.

That is a long way for a wire to travel that's picking up a magnetic signal. I ran mine to the front wheel for this reason.

You could try replacing the cable with a 2-core shielded wire, and connect the shield at one end to ground.

Or run it through a ferrite ring a few times , near the tacho maybe?