Shift Light

Is it possible to wire up a shift light to a 1975 Kawasaki Z1 ?  Not sure where I would pick up the RPM signal.  
Thanks.

 

wrote:

Is it possible to wire up a shift light to a 1975 Kawasaki Z1 ?  Not sure where I would pick up the RPM signal.  
Thanks.


 

Are you running electronic ignition - I have previously taken the pulse for a GSXR Tacho on a CB1100 Honda from the switched side of one of the coils (if you connect to both coils it doubles the speed signal) 

Yes it does have a electronic ignition on it. 

 

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Yes it does have a electronic ignition on it. 


 

You should be able to take pulse from the switched side of one of the coils - I did this for the Tacho on my Honda engined Harris Magnum to run GSXR instruments. It was running the factory Honda electronic ignition

wrote:

Is it possible to wire up a shift light to a 1975 Kawasaki Z1 ?  

I think it would help if you posted the model of electronic ignition you have on the bike and what model of shift light you'd like to use.

The electronic ignition is a Dyna S ignition and the shift light is a proform adjustable shift light.

BIGKEVIN post=871476The electronic ignition is a Dyna S ignition and the shift light is a proform adjustable shift light.

The shift light instructions show how to wire the light to the coil negative wire.  This same configuration should work fine with the Dyna S.  

www.proformparts.com/images/ePIM/origina...ght_Instructions.pdf

The shift light instructions show a green wire from the shift light.  This would connect to the black or green wire between the Dyna S and coils.  Pick either one, maybe pick green so they match.

www.mpsracing.com/instructions/Dynatek/DS2-1_2-2.pdf

This should work electrically, however I'm not certain it can be configured to read the correct engine speed with the dual-wasted-spark coil setup on the KZ.  It seems to assume the engine only has a single coil and a distributor?  Maybe you'd need to do something fancy to feed both coil signals into it?  Is there another option that can be configured for a 2-cylinder?

EDIT: I see they recommend a tach adapter for applications without distributors.  It seems a bit pricy:   www.autometer.com/tach-adapter.html

This one seems like it would work, but it doesn't look as cool:   www.proformparts.com/product-detail/6700...igital-3-wire-hookup


 

This should work electrically, however I'm not certain it can be configured to read the correct engine speed with the dual-wasted-spark coil setup on the KZ.  It seems to assume the engine only has a single coil and a distributor?  Maybe you'd need to do something fancy to feed both coil signals into it?  Is there another option that can be configured for a 2-cylinder?

As I said when I did this for a tachometer I initially wired it to both coils (using diodes to stop the coils triggering together) but it read double the engine speed. When connected to only one coil it worked fine. I would suggest connecting to one coil in the first instance and set the shift point at 3000rpm - if you have to rev to 6000rpm before the light comes on I will do you a diagram of how to connect to both coils with diodes
WARNING: I would suggest fitting a diode in the pulse wire to stop the coil trying to earth through the shift light and burning it out (probably not necc but better safe than sorry for a couple of bucks!)

wrote:

As I said when I did this for a tachometer I initially wired it to both coils (using diodes to stop the coils triggering together) but it read double the engine speed. When connected to only one coil it worked fine. I would suggest connecting to one coil in the first instance and set the shift point at 3000rpm - if you have to rev to 6000rpm before the light comes on I will do you a diagram of how to connect to both coils with diodes

 

Yeah, connecting both Dyna S pickups to the light using diodes is what I was suggesting would be "something fancy". 

You're suggesting the light would read double-speed, but it seems to me that it would read half-speed.  Configured for a 4-cylinder using a distributor and a single coil, the coil would pulse 4 times for 720 degrees.  On the other hand, on a KZ, connecting to a single pickup on the Dyna S it would pulse 2 times for 720 degrees.  Half the pulses would be read as halt the speed?  So wouldn't you need to set trip point to be double the actual engine speed?  So set the light for 18,000 rpm to get a 9,000 RPM trigger?  Note that the light only goes up to 16k.

 

wrote:

WARNING: I would suggest fitting a diode in the pulse wire to stop the coil trying to earth through the shift light and burning it out (probably not necc but better safe than sorry for a couple of bucks!)

www.proformparts.com/images/ePIM/origina...ght_Instructions.pdf

Also, note that the instructions have an interesting note about using a zener diode:

In the event your shift light randomly blinks or flashes try this possible solution...  We recommend you purchase a Zener diode with a voltage of 10 or higher...  Add the diode in line with your green wire with the diode arrow pointing toward the shift light.  In some cases, more than one diode may be needed. Just add the additional diode in the same manner as the first diode.

It's not clear why they recommend a zener here, but it goes on to say that more than one might be needed.  In a 12V system, two 10V zeners in series is basically just a normal PN diode.  I read this as helpfully suggesting that feeding the two Dyna S pickup signals into the light with diodes pointing towards the light is likely to work.

wrote:

wrote:

As I said when I did this for a tachometer I initially wired it to both coils (using diodes to stop the coils triggering together) but it read double the engine speed. When connected to only one coil it worked fine. I would suggest connecting to one coil in the first instance and set the shift point at 3000rpm - if you have to rev to 6000rpm before the light comes on I will do you a diagram of how to connect to both coils with diodes





 

Yeah, connecting both Dyna S pickups to the light using diodes is what I was suggesting would be "something fancy". 

You're suggesting the light would read double-speed, but it seems to me that it would read half-speed.  Configured for a 4-cylinder using a distributor and a single coil, the coil would pulse 4 times for 720 degrees.  On the other hand, on a KZ, connecting to a single pickup on the Dyna S it would pulse 2 times for 720 degrees.  Half the pulses would be read as halt the speed?  So wouldn't you need to set trip point to be double the actual engine speed?  So set the light for 18,000 rpm to get a 9,000 RPM trigger?  Note that the light only goes up to 16k.





 

I probably haven't made myself clear (I know what I meant in my head !!) that is why I said set the shift point at 3000rpm as if it reads half speed it won't flash until 6000rpm.When I used this method for a tacho connected to both coils it read double, I can only assume that the internal circuitry saw each pulse as 1 revolution. I guess ultimately if he sets the shift point low enough to "suck it and see" with out destroying the motor then he can always hook in the second coil if necc
My rational is that a car distributor will pulse the coil 4 times per revolution but runs at half engine speed (2 pulses per crank rotation) the KZ also produces 2 pulses per crank rotation but only 1 to each coil. Therefore 6000rpm crank speed would produce 6000 pulses per coil when the unit is looking for 12,000 pulses from a car system. which is why I suggested 3000rpm as an initial start point as the unit will be looking for 6000 pulses. which it will get with the unit connected to 1 coil

Thanks for the input.  As soon as I get time, I'll give these suggestions a try.