Were they pricey? I did the complete rear end conversion (wheel, shock, swingarm, brakes etc). Everything was fairly straight forward but unlike some of the others I've seen I decided to put aluminum bushings between the motor and the drz frame, I didn't want to have that much open space with no support. The bushings were something around 22mm inside diameter, but don't quote me on that, so I had to use scrap aluminum bushings my father and I had left over from tt500 flat track wheel spacers. I need to make some dog bones to lower the rear end of the bike. Hopefully we will put the motor together and in this week/weekend and we will get started on making a low pipe. The high pipe we made won't work because it gets in the way of the master cylinder.
All of this kx100 stuff I had laying around in the shop. I thought about doing the conversion about a year ago and found a kx100 with no motor or body work for 175$ or 200$ I can't remember the exact number. I started this conversion because I traded a set of subwoofers I had laying around for an absolutely roached drz 125 which I gave to my father so we could both have mad dog flat track bikes. It didn't have the correct rear wheel so between us we only had one good drz125 wheel so that really promoted the neccessity for the kx100 conversion. Here's what we started with and here's what my dad has done so far. We sourced a lot of cr85 and kx100 parts from my parts bin to save us some money. He used kx100 forks with a cr85 front wheel and drz 125 brakes and used a cr85 shock.
My bike is the one with the headlight. Dad's is the black front fender one. The green/back/yellow/white bike is dad's the day I traded the speakers for the bike.