ZG1200 DFI ??

[madmax]

For those who don’t remember a few years ago I asked the forum if anyone had fitted fuel injection to a voyager.
Well I have just fitted an old DFI system to my bike & it was relatively simple. I used a set of ZX6R throttle body’s & injectors.
The DFI system off a KZ1100B2 (GPZ1100B2) from the early 80’s including the wiring harness. This is the same system as used on the ZN1300 voyager. Now there were only 6 wires to connect to the bike. Battery Earth, Battery Positive, Ignition S/W., Two to the coils & one to the starter relay.
All the wiring has been done under the false tank, which made life easier.
Now to the Throttle body’s.
The carb spacing is totally different to the throttle body’s not only that, but the diameter is also different. So on to Ebay for some 2.0” to 1.5” silicon tube reduces. I had to cut them down to length to fit. Being silicon made them bend to shape easer & with a little gentle persuasion they were on. Throttle cables was the next problem. Too short by 3”, lucky for me I had a roll of Bowden cable. The cable’s no longer go to the center as on the carbs but to the left side of the TB’S.
So far, so good.
Now to the throttle position sensor Oh dear! It’s totally different in size & value. It also has a different connector. So I decided to use the original ZX6R TPS.
Where can one get the connector from I think. China ! Aliexpress & in no time I found the correct one. Two weeks later it arrived & I changed it over. Almost there I think. Now where did I put the engine temp sensor???
No good I could not find it. (I put it some place safe so I wouldn’t lose it.)
So off I went to my friend’s auto workshop for a VW/Porsche sensor. (Same Value) & a BMW / Porsche Air temp sensor.
So for those who have a ZN1300 you can still get spares that will work.
I had to just rest the air temp sensor above the TB’s as I’ve not made an air filter box yet.
Fuel lines?
Right, a different fuel pump is reqd. A High pressure one. I acquired one from a friend. (Free) For a Porsche 924. Also replace all the fuel lines with high pressure ones.
One thing you have to do on this system is find a fuel return to the tank. Lucky for me Kawasaki had put one next to the fuel tank filler neck which was blanked off. (Not anymore.) So all the fuel lines are now connected. Wiring connected, battery fitted. Fuel in the tank.
I turned on the ignition & the fuel pump ran for about 5 seconds. Fuel primed the system & I could hear the excess fuel returning to the tank. Again, so far so good. No fuel leaks.
I pressed the starter button.
Nothing!!
It didn’t take long to find the starter relay was no good. Lucky for me, I had a spare. Now the second attempt. Pressed the starter & within 4 seconds it started. Not bad for an engine that’s been sat around for a few years. I was surprised it started & ran as well as it did. It sat at 800rpm & ran smooth. It soon became apparent that there was a problem as soon as I opened the throttle. The ECU fault LED indicator started to flash. The code was for the TPS. Not surprising as the value was way off.
Now according to the manual, you can check the TPS by measuring the voltage on the pins. I knew the ohms was way off so by adding a resistor I was able to get the voltage readings within 0.1 volts of what was reqd. It now runs fine with no fault codes. Throttle response is instant. None of that delay you get with carbs & no fuel leaks. I’ve still got to make an air filter box for it. Also a bracket for the ECU & lots of small jobs to be done. But I’m happy so far.
Now that’s as far as I’ve got.

I’m still rebuilding the bike after getting the frame Galvanized. (Everything rusts where I live.) I’m still putting it back together. Trying to remember where I put all the bits and where they go?
It’s all come to a stop now until this next April, as I’m out in Thailand for the winter. It’s too cold & wet in the UK. Now I know some of you will want to know how it performs on the road. Well you will have to wait. I will let you know as the testing goes on. The system is a simple one. It’s not programmable. No Computers to connect & program with this simple system. But you can fool it by playing around with the engine & Air temp value & fuel pressure. Kawasaki themselves added a 270 Ω resistor in to the engine temp line on the last ones they made, to richen it up a little. This was an experiment to see if it could be done & so far it’s gone better than I expected. No more carb problems. Great!!
What more can you ask for.
I’m sure there will be questions. Remember this is an experiment & is ongoing.
Oh! Before I forget: A Merry Xmas to you all, from a sunny & very Hot Thailand.

[cranky]

... outstanding work!!! Thanks for the write-up and great on ya for
all your thought and work!!!!! Yes... Merry Christmas back at'cha!!!!!

[Nails]

Many thanks for trailblazing. You might think about opening a restaurant on that trail, as I'm sure others will follow.

[Barry]

looking forward to hearing about the road test. Maybe some pictures too ?

[madmax]

Hi Barry, I can not post any pictures as I'm not a "Green" member. So unless someone knows of another way of posting photo's
then you are out of luck. Sorry. I don't make the rules. At the moment I only have 3 photo's of the installation which I found on my phone.

[cbrfxr67]

This is some spanktastic work! Please post more! Some pics would be great too!