Jet and Pinasco 177 Au setup for VBB2T

I re-upload this post as a question (instead of a discussion), please help me out!


I have my VBB2T 1963 1 year ago from a the old owner and now I want to rebuild my engine for 5 - 10 years usage (at least). Therefore I decide to apply:

Pinasco 177 Au cylinder kit


SI 20/20


1/ For my engine. Is this kit good enough for the daily usage?

A lot of discussions have been taken place to discuss about the SI 20/20 and 24/24. I know the 24/24 allow more fuel and air mix into the cylinder but:



If 24/24 allows faster cooling system but consumes more fuel, I rather mix more oil into the tank. I ride the scooter every day thus I also want to save fuel cost.

(the manual book says 2%. But according to my experience after 1 month using 2% oil, the engine makes crashing sound (i think because of too little oil and too much collision between the piston and the case). My Vespa engineer told me that this sound wont stop until i replace the new cylinder.

Hence to due with the cooling effect, next time I will use 4% of oil for daily cruise and maybe up to 6% for travel around 200 km

The reason I choose this cylinder is because it's a Au kit therefore the overheat problem will be reduced.


3/ Do you have other choice for the Crankshaft? Or only 1 choice MAZZUCCHELLI. Which one is the best?


4/ Do I need to buy the racing crankshaft to balance with the Pinasco 177 Au kit (I just need my VBB for daily usage, NOT RACING)


5/ My VBB2T is 2 ports (i think) so do I need to do any modification to my old engine? I dont want to do any modification at all, so in that case, do you have other recommend kit to my need.


6/ I want to use my old exhaust, is that ok with this new kit?


7/ I want to run it the most EFFICIENT, most SAVING COST, and most DURABLE


Please answer my question 1-7 in order so that I could have all the necessary information for my restoration.

Thank you very much

1&5.  You can't put a 3 port kit on a 2 port motor, without having a machine shop cut a 3rd port (not recommended).  There is a 2 port pinasco 177 made of cast iron that will work on your motor.

2. a 24/24 carb will have higher fuel consumption than a 20/20 carb.  Adding extra oil to the mix is not recommended, it will actually make your mix leaner rather than richer.  Run the proper 2% mix, and adjust your jetting properly.

3. You have several choices on crankshafts.  Mazzucchelli, MecEur, PGO, etc. 

4. A pinasco 177 kit is NOT a racing kit.  Don't let the displacement or size of the kit mislead you, this is a very tame kit.

5. you say you don't want to modify your engine, what do you think this process is?  If you don't want to modify your motor, than just buy a new, stock top end.  

6. What is your old exhaust? Assuming the stock exhaust, no, it's not great for a kitted motor.  A kitted motor will need at least a Sito+ or SIP Road pipe.  Any expansion chamber exhaust will run the risk of scraping the ground if you're still running 8 inch wheels.

7. Efficient, cheap, and durable....... Buy a modern vespa.  Your best bet at trying to accomplish those goals are keeping your motor completely stock, and just replacing worn parts with OEM parts.