That carb link look's like the carb that came stock on my 09 jonway 50.
All i had to do is remove the end cap to adjust the air/fuel mix.
Can't say anything about rebuilding it as i haven't had to in the 3 years i have had this scooter, but if the need be i can.
Good carb and not a bad price/shipping.
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Now like SK said a 20 mm carb might be the way to go.
If you plan on installing a Big bore kit, sometime. (soon if your running too lean at WOT all the time) Then go with a 20mm carb.(yes you can use a 20mm carb as a replacement to the 18mm carb)
That 18mm carb will work just fine, and you might find it better for you'r current stock setup.
Ride,try then buy mod'$ .. you never know, but that stock EP carb, has got to go...