to the motorcycle by a pair of u shaped brackets 52 on the conversion assembly with their open ends facing forwardly to receive a corresponding pair of connecting lugs 54 extending laterally outwardly from opposite sides of the motorcycle 39 s rear wheel mounting frame 56 the u shaped brackets 52 are each connected to respective ones of the side legs 12 and 14 by a connecting bar 58 extending laterally and inwardly thereof into the receiving space 18 between the side legs 12 and 14 and at a location rearwardly from the inwardly converging diagonal side leg portions 24 and 26 the corresponding pair of connecting lugs 54 are connected to respective ones of the longitudinally extending side arm members 60 of the rear wheel mounting frame 56 by a bracket 62 bolted thereto and from which the lugs 54 project laterally and outwardly the auxiliary wheels 8 are connected to the frame 6 of the converging assembly 2 as follows a pair of wheel support shafts 64 project outwardly from respective ones of the side legs 12 and 14 at a location thereon about midway between the rear cross bar 10 and the beginning of the inwardly converging diagonal side leg portions 24 and 26 a cylindrical brake drum assembly 66 is secured to each of the wheel support shafts at a location radially offset from the center of the brake drum assembly on a radius which extends vertically and downward from the center a rotatable axle 68 extends outwardly from each of the brake drum assemblies 66 on which respective ones of the pair of auxiliary wheels 8 are mounted for rotation the conversion assembly 2 includes its own separate braking system to brake the auxiliary wheels 8 including a separate auxiliary brake pedal 70 which.