Originally Posted by Pablo
Indeed that is not correct. Your thinking is not right. "Designation" does NOT mean Del Orto part #'s. It means industrial number drill sizes. The table is for general usage and really just tells you drill bit equivalents, NOT Del Orto jet #'s.
Mine is a #65 which is .65mm. Your is a #68 which is .68mm. Stock is .70mm
This is NOT a bad thing. The thought is the these engines will run better (as you are seeing and feeling) by being slightly lean of stock. Good blind experiment!!
Ok......by what you are saying Delortto uses the jet size as the listing number. Basically take the number a convert it to mm. I feel that the 70cc would thrive with a bigger carb as well. Ive been doing alot of research and alot of what im gathering is that you want at the least a 17mm carb on a 70cc. The 14mm is made for the 49-50cc and just wont supply enough air to help the engine get to its full potential.