Modern Vespa

So I was shopping on a couple of websites for a big bore kit for my Piaggio Liberty 150 iget.

I remember looking at these awhile back and seeing that a CDI was required according to the listing for the big bore kit. Now that I am ready to buy the kit I noticed on scooterwest's site that the CDI's were unavailable so I asked the question, "Does the big bore kit require a new aftermarket CDI"

The answer I got back in my email was:

Answer:

We have found the bikes can adjust well enough with just the o2 emulator to be acceptable. It is essentially plug-n-play and simplifies the whole cylinder kit install.

Well enough they say, and yet on the scooterpartsco site it specifically says that the forcemaster CDI is required but does not show a CDI when looking in the piaggio liberty category but it does show the CDI with the big bore kit for the vespa primavera or sprint with the 150 iget engine.

Aren't they the same kit for both the liberty and the vespas with the 150 iget 3 valve engines?

And is it required or not? If I am going to spend $350 for the big bore kit and $130 for the emulator is it really well enough or should I get the CDI to go with it for another $150.

Maybe they have run a bunch of them without the CDI and found it to be just fine, it seems like that is what the scooterwest response is stating but isn't it better with the CDI? Why would both websites state the CDI necessary last year and now the scooterwest site saying nevermind you don't really need it? Is it just because they don't have any in stock to sell me?

Hopefully someone with better knowledge will pop in here and explain a little better. I thought about PMing Motovista but figured I should keep it public so everyone gets to see and then there is a record of it in the threads if someone has the same question in the future. It should apply to all of the 150 iget 3 valve fuel injected motors.

Thanks for your input.

Start at the CDI B4 you spend the money. Make sure it's plug and play. My Molssi CDI wasn't and I Don't splice important wires.

I am not afraid to splice/rewire if required but I am curious as to the model of both the bike and the part that didn't work together?

You make an excellent point however, and that is exactly what I am trying to do by starting this thread is find out what works the best for the iget 2017 and later 150 fuel injected engine.

I would really like to hear specifics from someone who has done this and knows. I was surprised to hear the scooterwest folks say" it works well enough without the CDI"

I think the stock setup works well enough I am trying to make it better! Also for my application I do have a spare engine to work with as well as wiring harness etc from a theft recovery parts bike. I can experiment and if it doesn't work well at all I can put it back to stock or any combination of parts that make it work the best.

I am not going to say I don't care if I blow up and engine but I do want to try a very high performance engine and see how it lasts and runs. You don't know what your limits are until you excede them!

So Malossi says to use a Force Master with the big bore kit, but the Liberty sent to the US isn't compatible with the Force Master they recommend for that year in Italy. I sent three different Forcemasters to one dealership, that has installed a lot of Malossi kits with forcemaster to Vespa Primavera and Sprints since they came out, to see if they could make them work with the new Liberty 150 iGet. They couldn't. I haven't reached out to our friends in San Diego to see if they'd be amenable to receiving the big box of Forcemasters that might work and having a go at it.
The bike does start and run without the forcemaster, and with the lambda emulator, you will get a bit more fuel at idle. Also, by unplugging the battery for a long time, you will cause the ECU to reprogram itself when you start it up with the big bore kit.
The issue that might arise from not using something akin to the Forcemaster is that the ECU in Piaggio scooters takes in information from the O2 sniffer up to 6000 rpms. And after that, it only does what it's programed to do. So if you're running the bike flat out for miles, you might be running it too lean for too long. I would definitely check the spark plug after a long run like that, and see if the bike is running lean, or okay.

Thank you very much! This is what I was hoping to find out.

So the force master CDI's work with the Sprints and Primavera's but not the Liberty?

That seems odd I thought the engines were the same except for gearing differences because of smaller diameter drive wheel on the Vespa.

There must be some other difference somewhere between the Piaggio and the Vespa for the CDI to work on one and not the other.

Also to be specific this is for all of the 2017 and up Liberty 150 (USA) iget engines? I wonder if there is a difference in the say 2020 and up Liberty but the first couple of years would work with the force master CDI?

I will keep my eyes open for an iget Vespa 150 project bike to dissect to see if I can learn more. Again thank you very much for the insight.