Over on YouTube we talk over the whole build about putting a CR125 engine into a CRF150RB. The frame and swingarm was cut up to get modern geometry. I saw a few people asking how much bigger this makes the bike. It ends up about the same size as the old KTM 105SX. The 150RB in stock form starts out a bit smaller compared to a lot of the supermini’s. To go along with putting the CR125 engine in and the frame mods, it has a fully hand made custom air box to keep maximum air volume for the 125 air boot and filter. A hand made aluminum gas tank that will make a 30 minute moto. A custom pipe to make sure it didn’t loose any power. Massive thanks to BBR Motorsports and Duane Brown for making this happen from the ground up. I wasn’t able to be there for most of it so this is mostly video that he texted along the way while doing it! We appreciate @Red Bull USA for supporting the build along with @Honda Powersports @MotoSport.com and @All Balls Racing. Dubya did the wheels, Dunlop tires,Bud Racing triple clamps, Rent