There are a lot of gear heads over at Total Ruckus , who know a lot more than me about these . This is what I do to all of mine , some people keep them stock and live with the BR gremlins . #1 change oil and add only one quart , Honda recommends 1.2 quarts which is to much oil . Using the recommended amount gives you oil blow back on to the air filter which leads to cutting air off to the engine . Then replace or clean the air filter . What happens is the oil blow back plugs the filter leading to a bad bog off the line . #2 Re-jet the carb to a 45 pilot and a 102 main , then replace bowl screws with hex heads . #3 Replace Honda variator with Jcosta . This eliminates the vibration on take off and the flat spot at around 5 MPH . And overall performance from 0 to top speed . #4 Replace rear shock , I buy the Bitubo because they work well and I like the looks of them . The Honda shock is not only weak , its unsafe . On a severe lean the rear tire can lose its grip , I know because I almost went down . That was enough foe me , I ordered the Bitubo that day . Thats pretty much it , now like Ive said before on this and other forums , some people are quite content with the BR stock . Im not one of them , thats for SURE ! When I did all of the above to my sons BR he said O MY GOD ITS LIKE A WHOLE DIFFERENT SCOOTER . I concur . Most people quite simply are just to cheap to spend the extra say $700 for the up grades , personally I wouldnt drive a BR without the up grades . But thats me . So there is your write up , short and sweet . TheReaper!