Pinasco Pinion or 3.72 transmission?

Hello S.I.P

I want to road tune my Vespa 50 s. 

I've bought a DR 75 cc cylinder and a 16.16 carb, and everything necessary for it to work. Now the site recommends a Pinasco 16 teeth pinion or a 3.72 transmission. But it does not explain if I'm able to put the Pinasco pinion in my Vespa 50 engine with the normal transmission ratios. Now the 3.72 transmission makes sense to me, because both cogs change size so the fit together. But i can't how see a single cog (the Pinasco Pinion) would fit into my engine and make it better?

But i hear that it's easier to change only the Pinasco, rather than the 3.72 transmission.

So am i able to just install the Pinasco on my original Vespa 50 s engine without anything else, or do i need something to go with it to make it fit? and which upgrade is better - the Pinasco or the 3.72 transmission?

I hope someone can help me! 

Regards

Kristoffer Munck

you can do some  gearing changes by removing the clutch cover..and the clutch which will expose the cog. this cog can be altered to a different one. do some maths to see what you can achieve with this limited change

For more l gearingoptions you will have to spit the cases and also change out the big cog that is riveted to the clutch basket.

when you buy a "Kit" eg Polini then you get BOTH cogs....and will have to select which particular ratio you need.

Different gearing makes a HUUUUGE difference