Modern Vespa

Hello good evening. My first post.
I’ve been fixing these things for years but I left the industry for pastures new.
I’m sure this has been asked before but how difficult is the transplant? And it’s my wife’s everyday transport. So can’t take too long.
The Mp3 isn’t too bad but it would mean she has to do a test in French, and go through registering the Mp3 in Monaco. ( headache).
We ve had Suzy the Vespa a long time and done 67000 kms on it, so I’d like to jazz her up a bit.
A dealer friend of mine reckons you need to run the Mp3 clocks as well as the obvious stuff and I imagine the engine mount is different. Anyone know for sure before I disable 2 bikes?
Thank you.
Tom.

Welcome, Tombatt73, to MV!

I haven't a clue, but I'm sure some of the more adventurous tinkerers here do. In the meantime, post some pics of the scoots in question. We are suckers for pics around here.

It’s not impossible, but it’s pretty difficult. Certainly not quick. And there are some unknowns here. I haven’t seen this exact swap done, but I can draw on my experiences from two other swaps that would seem to apply.

I have personally swapped a GTS250 engine into an MP3-250. It was an all-day, two-person job. While the two engines are essentially the same, they are configured slightly differently. If you have both GTS and MP3 engines, it’s not too difficult to switch the parts around.

I have also been a minor participant in a swap putting a GTS250 engine into a GT200. This was quite a bit more difficult. It required the wiring harness from the GTS to be transplanted into the GT, and that by itself took some doing -- especially around the headset, as the connections are different between the GTS and the GT. The engine was a pretty easy fit (the bodies are nearly the same) but there were a couple of places where new holes had to be drilled for mounting various accessories.

In the case of the swap you’re proposing, the MP3 wiring harness is likely a lot different, so you don’t have the advantage of going from a closely-related bike. The engines are going to be configured slightly differently (the MP3 engine is going to have an extra bracket on it) and it’s unclear to me if the cooling system on the GT125L is close enough to the GT/GTS to make the rest of the swap viable.

So, my guess is that the lack of a suitable wiring harness is going to be your biggest obstacle. If you can get a GTS300 wiring harness, that will likely go much more smoothly. Still, though, this is not a quick or easy job, and you will be in uncharted territory for some aspects of it. And some of the headset components just will not connect, so some customization will almost certainly be necessary.

Good luck to you, though.

I think jess has said it all really. It's largely uncharted territory for most of us so cannot give very much advice. Never ever did that professionally on a Vespa or any Piaggio. However, pretty much anything and everything is possible these days if you have the time and expertise. Do let us all know if you attempt this feat. You will be our test guy. Good luck!

Crazy enough, I’ve done this job. Or pretty much this job.

250~250

And let me tell you, it was a a total cork soaker mother clucker.

NOTHING worked, everything was different, sooo much crap had to be taken off or changed or modified or stolen from the parts bin.

As a professional, cut your losses. Buy a replacement engine and plug it in. Easy day job. Trying to reinvent the wheel on a daily only brings madness.

Also, pulling a motor from an MP3 suuuuccckkkssss