chinese tacho

Dear all,

I have fitted a chinese speedo tacho and need ur help
everything works but the tacho
it has only one wire black and yellow, I have attached it to coils, magneto with no results, only when I attch it to one of the stator wires a get a quick rpm reading then the needle dies and does not move, help needed please

Electric tacho,s normally have 3 wires. Black earth, red live, and a third which could be any colour which is the pulse feed. As yours only has one wire it must be earthing through the mount and taking live from however the unit is powered which means the remaining wire must be the pulse feed. This will conect to the pulse wire to the coils as a spur to tap into pulse to read its frequency.
Did it not come with a wiring diagram? If it did post it up so we can see the details.

Here is the same chinese tacho with a wiring write up.

www.kzrider.com/forum/4-electrical/60978...er-tachometer#795528

I got the wiring diagram, the pulse wire is on the 9pin connector "yellow/black

any help will be much appreciated

Hhhmmm, how does it know if its a single, double, four or six cylinder bike? Is there an internal switch to set?
Where on the dyno are you connecting too? These things are normally run from the pulse feed to the coil/s.

the internal switch is on the back, settings are for no. of coils instead of cylinder, so I set it at 2,
I have connected the black/yellow wire to
+ on coils
pick up coil
the only place I got a reading is from one of the yellow wires coming from the stator, but it only gives a short rpm reading when you first start the engine, then the reading returns to zero where it stays

When you say the + on the coils are saying the live feed to the coil or the wire that triggers the coil to release its power and make a spark. Normally the live coil feed on kawasakis is red and yellow. the trigger wire is a solid colour. Blue for one coils and Green for the other on my Z's. Its this "Blue or Green" wire it would need connecting too.

one coil has green and yellow/red, the other has black and yellow/red, I have tried all of them lol, but still no joy

OK so yellow and red is the live feed and you probably have one wire out the loom which splits to feed the two coils. The other two are the trigger / pulse wires. Its one of those two I would expect it to connect to. You mentioned you have all the other elements working correctly and the yellow / black on the 9 pin block that is the only wire not connected to anything? Kinda means it MUST be the correct wire. Either that or their translations into English are highly suspect!
Its not for something with an ECU is it? That would give a on / off reading rather than erratic peaks from points/dyno.
I know points/dyno type tacho's need a different chip in them to work correctly. Can you get inside to see how many connector legs the chip has? If it is an 8 connector leg LM2917 it won't work. It needs to be the 16 connector/leg version.

The yellow wires from the stator are AC voltage, not DC. The alternator on my bike puts out about 50 VAC.

For the tachometer some guy with a CB650 connected the sensor wire to the pulsing coil blue wire by back-probing the connector. I don't know if the Honda wiring is color coded the same as the Kawasaki, so you may have to try a different color wire. Most KZ electronic tachs get their signal from the black wire going to one of the ignition coils.

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Had the same Problems to get a correct rpm Signal. I have try all connectable posibilities and cheap low pass filter circuits with no sucsess!
Had to buy a ABS Signal converter to get clear square wave Signal for my DYNA III / KOSO RX2N+ Combo.

www.kzrider.com/forum/4-electrical/60769...eter?start=20#784802