Hello,

I'm trying to install the KOSO RX2N on my R125.. Now everything works, only the revmeter won't work
I've really tried everything to make it work but I just can't find it...
I've also gone through the wiring diagram and found out that the RPM-wire could be the yellow-white or the green-white, but none of those 2 works.. I've also tried to wire the meter to the ignition coil, but that also doesn't work...

I'm really out of advice now, is there somebody that can help me?

Get the wiring diagram for the r125 and check which one is the rpm

 

Get the wiring diagram for the r125 and check which one is the rpm

I can't find it on the wiring diagram.... They say the Tachometer is number 57 but there isn't a wire comming from number 57...

 

Okay so 57 (Tach) is inside box 55 which is just the whole dash in general, the only two wires I can see that aren't accounted for are the Yellow/White striped wire and the Green/White like you already said. Have you tried revving the bike and probing each of the wires with a multimeter to see which ones change voltage?

 

Okey, so I checked the green/white and yellow/white wires for their voltages while revving the bike but none of them gave an actual result.
The only wire from which the voltage changed a little bit was the yellow/white wire but while revving it only gives a voltage of 0.003V and idle a voltage of 0.020V ?

I really don't know what I'm doing wrong Can it be that my ECU is broken?

Wait I will upload the videos in a second
Yellow/white:

Green/White:

 

Looks like maybe it is that Yellow and White, it's perfectly normal for it to decrease voltage as you rev, but I don't know if the KOSO works that way, not really sure how to help!
How many other wires have you already got connected?

 

I only have the power cables connected & ground... But I've found a movie on youtube of an r125 who has also the rx2n and he says this:

anuk punk 2 maanden geleden
Hey , to connect the first need rx2n koso each wire which
is the bike, turn signals, high beams, etc. ......... short and connect each
cable IMPORTANT RPM cable connecting the coil lit.
sry for my bad english google.

But what is the coil lit?

 

PS. Do you know what kind of signal the KOSO meter is looking for?
I guess if you wire up everything else that you know, then you'll only have a few wires left over, and whichever one does the right thing will probably work

 

I've tried to wrap the RPM cable around the spark cable and now it works a little bit haha
And i've measured the voltage that goes trough the RPM cablewhile wired around the spark cable and the KOSO meter is looking for a raising voltage...

This is with the RPM cable around the spark cable:

As you can see as soon as I stop revving, it immediatly goes to 0 rpm & also if I idle at 6k rpm it stays at 0 rpms..

 

I don't know what else to suggest then, other than find other R125s with it on and ask them, or wire up everything else and try whatever wires are left!

 

This problem sucks man. That speedo is the sex!

 

Only r125 with shift light

 

Almost as good as yours mate

 

That looks beast haha

 

have you tried wrapping it around the spark plug a few times, maybe 5 or 6?

 

Why? Haha

 

http://www.kosonorthamerica.com/fCMSBackend/imgRoot/inst/BA010001.pdf
here you go dude, under the diagram, tells you how to install the RPM wire

 

if in doubt, consult the instruction manual

 

Pfft, that's for stupid people and women

 

If you were going to put it on the spark, you'd probably want to do it before the coils wouldn't you?
The spark plug has quite an unstable electrical signal (being a spark), whereas the initiating current would be a more stable pulse.

 

I assume that before the coil would be a very small signal, it doesnt need a stable signal all it needs is the big voltage spike, the rpm is calculated by counting the amount of these spikes..... I think :L

 

It won't need a large voltage to run. I've just been reading the KOSO manual and it recommends pre-coil if you can't find the original tach wire, the spark splug just isn't a good reliable source as the actual signal wires on other parts of the bike.

Any progress yet Dimitri?

 

Almost as good as yours mate

Yea

 

Fair enough xD I was just educated guessing at how it may wrong never said I knew I was right lol

 

No it's good logic, as long as the spark plug was a single high-powered pulse, but sadly it's not; it's got some big interference in it, due to the way the spark is actually generated

 

Nope, still no progress..
When wrapped around the spark cable, the tachometer doesn't work well..
But I've also seen that the engine management light is on because I disconnected the original speedometer
Maybe that why I can't find any wire that gives the rpm?

I will take a look at it next week, because I've already put everything back on.

I also find it weird that when connected to the negative side of the coil, I don't get an rpm signal...
I've measured it and it gives a raising voltage as soon as you rev (starting from aprox. 12v)

 

Well, I got an answer from the guy who installed it on youtube

anuk punk 1 dag geleden
Hello,dimitri,install the RPM cable to,ignition coil.Koso select number 7 button menu, put P-0.5 ok?.

But what is the ignition coil? xD

 

Well, I got an answer from the guy who installed it on youtube

anuk punk 1 dag geleden
Hello,dimitri,install the RPM cable to,ignition coil.Koso select number 7 button menu, put P-0.5 ok?.

But what is the ignition coil? xD

The part before the spark plug cap A round little cylinder thingy

 

That's an awesome looking dash how well does it fit does anything need altering to get it to mount?

No phased by the wiring as I've got a Vauxhall Astra GTE digidash fitted in my XR2

 

I'll ask what may sound a stupid question but have you wired it to the positive side of the coil.

 

Yes, I've wired it to the 12V input side

 

Ok does the dash need to be set up as in do you need to press buttons so it knows that it's a 4 stroke. Can you not wire into the existing wires for the revs or has somebody already mentioned that?

Perhaps it works off voltage rather than pulses if that's the case wiring to coil wouldn't be much good and wrapping around the plug lead would be a bit intermittent.

 

Ok does the dash need to be set up as in do you need to press buttons so it knows that it's a 4 stroke. Can you not wire into the existing wires for the revs or has somebody already mentioned that?

Perhaps it works off voltage rather than pulses if that's the case wiring to coil wouldn't be much good and wrapping around the plug lead would be a bit intermittent.

Normally there has to be a wire for the revs, as the original meter also has a revmeter, but I can't seem to find it.....
I tought the yellow/white or green/white wire, as they both go into the ECU without going anywhere else, but they don't give any voltage changes when you rev.

And yes I've set the settings to 4-stroke & 1 Piston