Vespa PX125 conversion




I couldn't take it anymore. I had to clean up to a minimum level. I couldn't find tools and I was tripping over everything.

Now back to getting it dirty again! :D


Because my battery is VERY tight, I added two layers of shrink wrap to the battery for a bit of extra protection. The base will get a 1/8" sheet of nylon for abrasion protection.



Sealed up the battery bracket and rust treated the inner fender. It will also get undercoating.

Test fit the swingarm, fits perfectly.

Started front end disassembly for cleaning, lubing and painting.

New shocks on the way.

I think I am going to fully box the swingarm, more to keep dirt out than anything.

Almost all parts are in, except the motor, controller and rear brake. I need them to move too much further on the electric side. Still a little bodywork and fab for the handlebars to do.

Making the clean shop messy again.


rich c

Well-Known Member
I've never seen anyone put Bondo on top of spot filler. I was taught the other way around.


Yeah! My motor and controller came in. Not bad at all.

Boxes were heavy and protected the parts well.

Useless, to me key switch. Nice quality, but I am using my stock switch.

The throttle looks like it will work, despite the ding in one of them.

Brakes came all in one piece, prebled. I will have to take it apart to install them.

And, of course, the huge, but stout Kelly Controller. I am looking forward to setting this up:

Next the QS 205 4KW 10" hub motor. Well boxed, very well.

In perfect condition, brake rotor preinstalled.



I took a few minutes to see if the brake kit would work well, and it appears it will:

This guy struggles with it:

Lastly, a question: The torque arms are very loose, moving 1/4" at the tip. You can see the slot has a significant gap:

It is barely over half the thickness of my swingarm dropouts, and they are very snug, plus will be pinch bolted. Should I still use them?

If yes, is there any reason why I can't curve them to fit my swingarm, then drill and tap it for a bolt?

Anyhow, here is today's haul, plus many parts behind them. I will lay all my parts out and label them in a future post when the last remaining pieces come in.

I don't really do unboxing videos, but this guy did one. (Same guy who had trouble with the brakes.

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I added another internal crossbrace, drilled and plug welded, plus perimeter welded. Then I boxed in both ends. It weighs 28 pounds. If this isn't strong enough, nothing is.



At this point I would be better off paying a pro to build this to my spec. I have at least 15 hours in fab, and another 10 in design.

Nonetheless, I am pretty happy with it, and learned a lot. My welding is steadily improving. It is STOUT!

The addition of the shock mount was problematic. Angle and clearance. I will have to mod the new shock when I receive it. Yes, single sided.

Then the brake mount messed with me. I ended up with the caliper upside down. Not ideal. I will be looking at it more tomorrow. Note the bolt threaded through both sides of the swingarm, and into a bushing on the caliper mount.

Lastly I made a small error in building the swingarm and did not leave enough meterial for the pinch bolts, so I added it.

Also my paint came in, Green and off white. That will, maybe, be next weekend.

Tomorrow I start working on the hydraulic brake mount and positioning of the components.


Modded the handlebars to fit the rear brake lever and master cylinder, and the electronic throttle. The Vespa had a shifter that you activated by rotating the left bar to select a gear, while pulling the clutch at the same time. Kinda odd, but you get used to it. The throttle was a cable, and the bar was too large to fit the electronic throttle, so I had to fit a smaller bar. Then both bars needed to be staked into the headset to the would not move or come out.

Then I rubber undercoated the inside of the fender and underside of the leg shield.

Next I started working on positioning of the major components. I think the Kelly Controller will fit perfectly where the battery was, and the 12V DC/DC converter will fit next to it. Most of the other components will go inside the fuel tank area.

Finally I installed the tire and tube on the hub motor. It was a bit of a pain. I would not want to do this on the road. My only concern is the valve stem is contacting the hub. I need to find a way to move it so that it doesn't wear through and cause a flat.



Fixed a couple of issues. Shrink wrapped the valve stem. It isn't really tight on the hub, so this should be good. I also chopped off a bunch of the shock mount to make it less bulky, then boxed it in.

Used rust reformer on the inside of the side cowls and front fender.

Received and checked the fit on the new LED headlight.

Cleaned the front axle, brakes and centerstand.

And from now on I am working towards paint next weekend, so lots of sanding, cleaning, sanding, touch up spot putty, sanding, and then primer, sanding, and paint.

Parting shot:


Sanded down everything that will be painted with 400 grit paper. Cleaned up, again, and sorted all the conversion parts to the back workbench.

That is about $1900 in parts there. A couple small items missing.


Well-Known Member
Silicon Valley
Vespa's are very collectible these days... soon everyone will want an electric scooter! 😉

Vespa Elettrica electric scooter begins sales today in EU, next year in USA (