Maybe this should be in the "other bikes" section? I'm sitting inside on a winter day (waiting for spring!) and perusing thru U tube when I came across a video of someone who removed the engine and front / lower frame cradle from a Yamaha IT 175. This was all replaced w/a 150cc chinese(Honda clone) engine. There wasn't much wrong w/the Yamaha engine, he just liked the 4 stroke better. I'm pretty sure it wasn't one of our GasGas friends; the footpegs were mounted backwards, the exhaust was beyond belief( it looked like it would boil the gas in the tank!), the carb was mounted directly to the engine- no spacer for vibration and subject to more heat, the airbox was pitched and a clamp-on filter installed and the engine looks like it would bottom out before the suspension fully compresses. Many years ago I crammed a Suzuki 100 engine into an RM 80 chassis. The RM 80 was free and the 100 I bought from my nephew for $35. It didn't turn out that well but it was a good bike for my daughters' to learn on. If they broke something or just didn't like riding, so what? I was wondering what anybody else had seen in the way of "hatchet-job" dirt bikes? Jim