Modern Vespa

Hello everyone,

Greetings from Transylvania!
You can skip the intro and go to problems part
A little intro about myself: back in 1999 my father bought a moped, it was a Tomos Targa and that's how 2 wheels madness started for me. I drove that Tomos until the sprockets broke, the my father bought another moped, a Ramzey Wolf. The end for this one was when the cylinder broke. I didn't have any mechanic knowledge back then and the spare parts were very hard to find.
It was 2006 when I first drove a Vespa. I think it was a PK; it had manual gearbox and 80cc cylinder.
In 2008 I got my driver's licence and I bought a Kymco Grand Dink 250. I kept that scooter for 5 years and I've put more than 60000 km on it. I also learned some basic mechanics. Finally, in 2013 the cylinder broke after just 5000 km after replacing it and that was the moment when I realized I have to move on. The 250cc engine was quite small for my needs and I was fixing it more often than I was riding it, so it was time to move on. In 2014 I bought a 600cc Honda Silverwing and I put around 20000 km on it since then.
Lately I found that the Honda is too big and heavy for daily commute and after I rode a 150cc ET4 I felt in love
This year in February my girlfriend started to think seriously to get a motorcycle, but I thought it would be best to accommodate with the traffic on a scooter, so we bought a 97 ET2. I didn't do too much research when I bought it and I didn't realize the fuel consumption until after I bought it. The fuel consumption is around 4 liters for 100 km and that's a lot for a scooter that can't go faster than 60 km/h. This is the end of the intro is this is where problems start.
I searched for a way to swap the ET2 engine with an ET4 engine and after reading many topics on this forum I found out that I needed the whole wiring loom, with contact, CDI and so on. On this research I found out that there are 2 engine types (the LEADER and the Non-LEADER) and I lived on the wrong impression that only the LEADER has an immobilizer.
I found a good deal for an used ET4 125; the seller stated that he didn't have the ignition and the engine can't run, but that didn't bother me at all. I just searched the VIN in stolen motorcycle databases, it wasn't reported as stolen so I bought it.

Problems
After I bought the ET4 I found out that even non-leaders have immobilizers and I knew it was bad news. The previous owner also tried various work-arounds and made a mess in the wiring loom.
I almost sorted the wiring loom and I will try my luck to bypass the immobilizer with an Aprilia Scarabeo 150 CDI. For now I would like to know if the NON LEADER HT coil gets 12V on the purple wire just as long as the start motor or the engine is running. The main idea is that I don't have a spark. I removed the immobilizer and the original CDI.
Can someone please have a look at the workaround I tried and tell me what did I do wrong? Here's the ET4 wiring and in the attached PDF there is the Scarabeo wiring diagram. I considered the left wire from Aprilia CDI (42 in the diagram) as 1, the 2nd one as 2 and so on and here are the connections I made:
On Aprilia----------On Vespa
1--------------------W
2--------------------V
3--------------------1
4--------------------R
5--------------------B
6--------------------G
The other 2 wires from the original CDI were removed (the one connecting the CDI to the diagnostic port and the one connecting to the immobilizer.
My problem now is that I don't have a spark and the HT coil gets 12V on the purple wire only as long as the engine starter is spinning. I have 2 questions about this:
1. Is it normal that the HT Coil gets 12V only as long as the starter is spinning? Is it gonna continue to get 12V as long as the engine is running?
2. How do I measure if the HT Coil is working properly?

Thanks for reading this long post and I hope someone can clear things for me.
George

You would be better off posting in the general discussion area as that is where they discuss four strokes

it's my first post on this forum and I can't move it. I hope and admin sees the topic and moves it if necessary.

If i understand you correctly you are trying to get a per leader engine to run on a leader cdi ?
If so good luck with that one as the two electrical systems are completely different and won't talk to each other.
The leader generator is a 3 phase and has a signal pulse for the cdi pick up, the pre leader engine has two signal wires from the pick up the leader has one.
So other than transplanting the leader engine stator plate, cdi pick up and voltage regulator and rectifier (which don't fit) it's a big headache.

There is a cdi with immobiliser bypass specifically for the pre leader engine, it's plug and play and made by beedspeed in the UK, it retails for about £70·00.
Cheers Andy.

no, i'm not trying to use a leader cdi on a non leader engine.

i am trying to use a Aprilia Scarabeo 150 CDI to the non-leader engine. have a look at both electrical diagrams, they are in the 1st post and then have a look at the wire setup I made.
basically I managed to send 12V to the HT coil, but I am not getting any spark. I will take some measurements of the HT coil tomorrow.

Won't work no signal from pre leader stator

That's some bad news for my low budget project

Hi, you are trying to attempt for want of a better assymalee
Connecting a HDMI cabled appliance to a SCART socketed appliance by joining the wires from both and expecting them to talk to each other and work.
Cheers Andy

Yes, I got that. Basically the vespa sends AC to the cdi, while the scarabeo cdi works on DC. I might get it to spark, but it won't be reliable

So I bought a non-imobilizer cdi and I managed to start it. It cost me about 40 Euros.
I now have to sort the wiring loom, as when the engine is runing I have a blinker light switched on all the time.

Hi,
Glad you got it started, just isolate the blinkers and wire a seperate circuit using a seperate relay, 10 mins work, £5·00 materials.
Cheers Andy.

Since there were a lot of wiring cuts on the existing loom, I need to isolate them and maybe I will get the issue fixed. If not, I will put a separate circuit for the blinkers, as you suggested.
Thanks for your support, Andy!

It's been a while since my last post here. In the mean time, I managed to start the 125cc engine. I also bought a new wiring loom. However, I still have some problems.
I am not sure that I connected properly the new wiring. Here's what happens when I touch the throttle: I can't figure out what is the connection between the throttle cable and the electrical wiring...
I also have some sparks when the cable from the idle screw touches the engine.
If anyone has a 1255cc non-leader I would appreciate a picture of the wire connections in the battery compartiment with the starting relay and what else is there.