In addition we only use top grade fuel, we have found that "bottom grade" pump fuel does affect performance and when you are talking 6 cents difference on a machine capable of over 100 mpg, 6 cents is not an issue. Like I have said in another post we do change all vacuum lines, fuel lines and fuel filters before we start them for the first time. As a Roketa Dealer (brick and mortor store) every 50cc ( actually 49.7 cc by the MCO) that we have gotten has done at least 35MPH out of the box except for one "PIG" that would only do 25, which was a piece of "crap" in the carb main jet, an easy fix. I can not speak for other manufacturers but I can for Roketa.
Or do you have two 50cc scooters, and one can go faster than the other? So being 5mph off is probably normal up there. Of course you are way up high there in Colorado, as I understand it, that has a serious impact on engine performance. It might simply be a carb or cam that is the problem with not getting that extra 5mph out of it. There are four basic 50cc engine crankcase designs, ATV with short stub axle for a chain sprocket a short case used for small 8 and 10 inch wheels and a long case design used with 13 inch wheels since there are some scooters with 16 inch wheels there is a longer case design too, but the engine case for the 13 inch wheels might work for this one too (I don't know). The police impounded the moped and removed the head and cylinder as being illegal, then let him have it back. I remember a number of years ago reading about a teenager from the Netherlands or Belgium getting caught going over 30. it is to discourage 15 YOA teenagers from easily hopping up their rides. They've actually built detuned 50cc engines for that purpose. So it should not be surprising to run across engines that seem to not go faster than 30. Such as a good deal on a contract that fell through and they have 500 engines surplus from something.īasically, in some countries a 50cc can't go over 30mph to be considered a "moped" or something, so the engines are tuned for that. Heck they probably just go for what they can get at the moment. The manufacturer orders a batch of engines, they may or may not specify engine performance parameters, so different engines can be bought and used. Since these 50cc engines are so generic and umbiqutous, the parts are amazingly interchangeable. there are known differences between head and valve designs, where one head has smaller ports and valves than another has. They can put in different cams and ignition modules for different purposes. There are actually several different QMB or GY6 style 50cc engines out there.