Fuel Efficient Carb

[davscott]

I'm looking for a fuel efficient carburetor for my 50cc GY6. Any suggestions?

[tortoise2]

Oct 18, 2018 7:49:03 GMT -5 davscott said:

looking for a fuel efficient carburetor for my 50cc GY6

Context . . most queries on this forum are for the opposite?

The sealed carbs on new 139QMB engines are typical jetted lean.

Deni carburetor with 78 main jet . . link

Deni carburetor with 85 main jet . . link

[90GTVert]

Tuned properly, a stock carb should be quite fuel efficient. If stock is hard to tune because it is sealed or has no needle adjustments, replace with an 18mm-19mm CV carb. These things should get 80MPG and beyond on a basically stock scoot.

[ratdog]

Already said, but I’ll replete. For best fuel economy you want a small carb jetted lean, which is what the bike comes with. I have not seen and aftermarket carbs in 17 mm ( I know there are bikes that have them stock, but have not seen them for sale) so really you are working with a 18 mm. It might be good to get an aftermarket carb that we have more adjustment options, but frankly I doubt you can run much leaner then stock. The exception might be if you lived at higher altitudes, like over 3000 feet. Then going leaner might be a good thing.

The issue you have, is that only have 3 hp to start with. And stock bikes already tend to run hot. Lean it out more and you will loose power and increese heat. Both bad things

Never really thought much about it before, but you might very slightly increase your weights inside the CVT, which would move your RPMs down a little when accelerating, and therefore give slightly better mialage, but that would also tend to make your bike accelerate slower. Of course you could change your overall gear ratio to run at lower RPMs but that would destroy your acceleration.

Of course you could also decrease weight to get better mileage. But frankly, it a lot easier for you to take off weight then to get weight off these little scooters.