Guess I have built just about all kinds of MBs but never a push trailer. Figured I would give it a shot. The trailer is made from scrap left from our old house renovation. Uses a wheel barrow wheel with a 72t #35 sprocket welded to it. 212 Preddy thru a TAV 2 clone. The TAV is the only way to go these days @ only $52 shipped why fool with a cent clutch. Ratio is a 4.8:1 which starts off at a 12.8:1 and ends up at a 4.32 if it reaches OD. Figures to the low 40s with the governor, the Preddy is governed at 3800 instead of the usual 3600 With out I bet 50+ is easily possible. Really just want a relaxed cruise in the upper 30s. The thing is not as ungainly as it looks in function, is very quiet and is as vibration-less as an ebike. Has worked very well is the short time I have used it. Cool thing is my wife got a steal on a nearly new Schwinn Meridian and it will quickly hook up to it. Will hook up to various bikes we have. I made a two sided seat post to adapt the bigger posts. Its got skid rails on the sides to protect the engine should the need ever arise-- hopefully not!