177cc/si20/20
Posted: Thu Dec 13, 2018 2:47 pm
Can vespa 177 kits be successfully run with si 20/20 carbs or is 24/24 a necessity. mine would be a BGM in this instance, but also like the look of VMC.
You can run it with a 20/20, no problem. The benefit of the larger carb would be to provide more air flow, and correspondingly, more fuel. This allows for higher RPMs and more speed. But with the smaller carb you would expect to see better throttle response and performance off the line. This is due to better atomization of fuel at lower RPMs and smaller throttle openings.
Personally I like this thing for the 20/20 carb.
https://www.shapeways.com/product/ZFBJ7 ... arketplace
It's a velocity stack and is sort of a best of both worlds solution. It's not as good as having a bigger carb, but it will let the engine breathe a little bit better and may make an extra pony or so. And you can't beat the price.