Re: Any x7 big bore heads?
There is no 53cc pocket bike piston port engine, don't believe everything you see, 96% of the sellers lie like a Rug. MPR claimed my 47cc Cag with maybe 3 horses had 5 1/2 hp, it's a bare face lie. Or, they say there Cag will go 45MPH w/ some mods, yeah, if you spend $1,000 or more dollars on a $169 bike. If it has a 44mm bore its a 49cc engine, I do not care what they did to the cyld. The reed ports and three cyld upper port channels and call it up to 54cc, its the some old 44mm bore. If you have a 44mm bore cyld already, there is no bigger, unless you can make a Stihl cyld fit and piston your cases.
The word B/B big bore kit came form the early 47cc, really 39cc Cags., 40mm bore and 40mm piston w/ 10mm pin. Then they came out with B/B kit a 44mm cyld & 44mm piston with a 10mm rod pin and bearing to fit the stock crank. The factory 49cc Cags w/ 44mm bore & 44mm piston that has a 12mm pin and a HD 12mm crank.
Empty Pockets Racing: The difficult we do, the impossible takes longer.....