Letting the 125 supermini sing around The Trailer Park MX. If a brand produced a supermini sized 125 2-stroke, would you get one? We get a ton of questions about this full custom BBR Motorsports Supermini 125 build, so here is a rundown. This is a complete one off Supermini sized bike that we put a YZ125 engine into. I have tons of fun ripping Supermini sized bikes but struggle to keep them alive as an adult. We talked about just building a aluminum framed Supermini to keep the frame from bending and breaking everything around it. But had also talked about putting a 125 into a Supermini so that it has tons of fast, fun, and reliable power. My dad (Duane Brown) got to work on this dream project putting in over 300 man hours of milling, welding, machining, and grinding to make this thing a reality. This is NOT a cut down 125 frame, he made the frame from scratch. Nothing off of a YZ125 frame was used. By the end of it he made a full one off aluminum Supermini frame, linkage and swingarm...