1957 Moto Parilla 125 2T

[bhh1989]

I thought you guys may enjoy this due to the oddities of this old 2 stroke motor. This bike was imported from Italy in '91 to California and remained untouched until I purchased it several years back. It is one of about 4 in the country that I know of, but they are somewhat easy to find in Italy. It had all the right stuff for an easy restoration or at least a refurbishing - strong compression, spark, squeaky clean tank inside.. but no carb. I sourced a NOS carb from Italy after much searching and Google translating. Then I started working on it!

[bhh1989]

After researching and verifying the correct jetting, cleaning the taps and changing the oil, I poured in some HEAVILY mixed gas (the original manual calls for like 20% oil to fuel.... I put 18:1 waging on advances in 2T oil since Italy 1957). She fired about just a few kicks, but it didn't rev well. After much tinkering with carb settings, it still wouldn't run well and would hardly pull.

I decided to investigate beyond just taking off the head like I had already done. Much to my chagrin, I found this little hole in cylinder wall. The piston was the max overbore than was available at the time too.

[bhh1989]

I have many Parilla sources around the globe and was lucky enough to source a NOS cylinder, piston and rings, as well as a new gear selector (which is external). Take a look at this weird piston design:

[bhh1989]

I have a philosophy about taking off parts and reassembling - if it gets taken off, it doesn't go on until 100% clean. This is the rear of the motor after cleaning, where the external gear selector is attached:

[bhh1989]

I dipped the NOS cylinder in light phosphoric acid to remove some light surface rust from 60+ years of storage life, then repainted it, honed it and reassembled the motor. The bore itself was not rusted at all thanks to the creosote. Here is the cylinder after dipping:

[bhh1989]

And after restoration:

[bhh1989]

She runs better now, but I suspect the timing is off, it just doesn't rev well at all. The flywheel on this motor has a super weird thread size (M26 x 1.25 RH) which I will have to have a machine shop make a puller for. But she still had enough LOW END power, which is more than it has top end, to take my wife and I uphill in the grass at the Barber Vintage Festival campground and around the site roads. It was quite a site.

[RDryan]

Amazing you got her to run with that hole in the cylinder! Pretty bike I never knew of. I hope you get her sorted soon and keep us posted with the progress. 

[m in sc]

I so love this project 

[tony27]

I have many Parilla sources around the globe and was lucky enough to source a NOS cylinder, piston and rings, as well as a new gear selector (which is external). Take a look at this weird piston design:

Strangest looking deflector piston I've ever seen, only ever seen 1 lump. Looks to be from when directed flow from the transfers first started to be understood
Spent a look of my childhood on the back of 50s & 60s Jawas & their pistons were very conventional design where the Moto Parilla is a cross between 30s era & what we have now
It's really interesting just how easy it is to get parts for a lot of Europeon bikes compared to Japanese bikes

[Czakky]

This is such a cool project! Reminds me of the Silk/Scott pistons.

[Czakky]

Also this months issue of Motorcycle Classics has a spread of 50cc 2t Italian motorcycles.
Viva Italia!

[bhh1989]

I uploaded a video of my ride at Barber this year to YouTube:

https://youtu.be/CEYblP1ZIXI

Here is a video of the phosphoric acid doing work. I use this stuff a lot.

https://youtu.be/CEYblP1ZIXI

[bhh1989]

Side view.

[bhh1989]

Other side.

I know, get with the program, stupid way to upload images.