Koso Tachometer/speedometer on GS 1000

[John Kat]

I had another go at getting the tachometer to work today.
First, I tried to wrap about 8 coils of wire around one of the spark plug leads and despite changing the polarity of the input, I got no rev indication whatsoever...
Next, I went back to connecting the tacho input wire directly to one of the coils but this time I used a 24.7 K ohm resistor in series.
The result is still very disappointing: at idle it works fine except for the needle that dips from time to time but when the engine revs above 4K rpm the needle wanders up and down by approximately a 1000 rpm.
Great! I didn't need a rev counter to get this level of approximation...
Koso North America answered my request for help by saying that I had to call Koso Europe.
That's very kind except that I bought the device from the USA as it is NOT sold in Europe.
No fun so far!
Update: I got an answer from Koso in Germany!
They stated that I had to get the signal from the electronic ignition pick up sensor.
It was in the manual but for some reason I didn't register that possibility...
I'll try tomorrow!

 

[John Kat]

Following Koso Europe's advice, I wired the tacho input wire to the electronic ignition pick up sensor.
I chose the blue wire and bingo IT WORKS
The indication is very stable from 1000 to 8000 rpm.
The good news is that I realize that I'm must have been shifting 1000 rpm too early before...
Gone is the hesitation of the original 30 year old instrument cluster.
I would highly recommend the device at least if you have an electronic ignition on your bike.

 

[Chris G]

Good stuff, I looked at mine earlier it was installed before I bougt it, but there is no wiring wound around any of the coils, plugs etc, appears to be as you state and wired direct to the coil pick up.

 

[Wheelbreak]

Following Koso Europe's advice, I wired the tacho input wire to the electronic ignition pick up sensor.
I chose the blue wire and bingo IT WORKS
The indication is very stable from 1000 to 8000 rpm.
The good news is that I realize that I'm must have been shifting 1000 rpm too early before...
Gone is the hesitation of the original 30 year old instrument cluster.
I would highly recommend the device at least if you have an electronic ignition on your bike.

Thank God for this thread!! I was ready to chuck this thing off a cliff. I just spliced to the blue wire you indicated and it's working great now!! The connect to the pick up sensor graphic in the instructions was confusing to me, and I tried every other method that pertained to my bike with no luck.

 

[John Kat]

Thank God for this thread!! I was ready to chuck this thing off a cliff. I just spliced to the blue wire you indicated and it's working great now!! The connect to the pick up sensor graphic in the instructions was confusing to me, and I tried every other method that pertained to my bike with no luck.

Glad it worked for you!
For some reason, I also got confused by the instruction sheet?

 

[Wheelbreak]

Quick question. Do you have any issues with your battery draining? I have read other people have this issue as well, and am wondering if it is my wiring job.

I ran a new wire to the battery +terminal for the red constant power on the koso. Used the orange wire that powers my lights to the brown wire on the koso for the ignition on power. Then I use one of my spare black and white grounds in the headlight bucket for the ground.

The gauge works well, but my battery seems to be draining. I am going to order a new battery today to start from scratch because my old battery will no longer hold a charge. This is ridiculous because it's only a year old.

 

[John Kat]

Quick question. Do you have any issues with your battery draining? I have read other people have this issue as well, and am wondering if it is my wiring job.

I ran a new wire to the battery +terminal for the red constant power on the koso. Used the orange wire that powers my lights to the brown wire on the koso for the ignition on power. Then I use one of my spare black and white grounds in the headlight bucket for the ground.

The gauge works well, but my battery seems to be draining. I am going to order a new battery today to start from scratch because my old battery will no longer hold a charge. This is ridiculous because it's only a year old.

I haven't paid particular attention to this so far but I could measure the current consumption for you.