There are two versions of the Yerbi: 1. Race Package 2. Street Package Race Package Includes:  NEW Derbi GPR Engine Motor Mounts for YSR CDI and Ignition Coil Clutch Cable  Shift Lever Most of you racing YSRs already have a 24mm carb and pipe. The pipe for the YSR can be easlily adapted for the Derbi, or we can supply the pipe. (The YSR pipe works extremley well when adapted to the Derbi engine). The 24mm carb bolts right on. You will need a radiator. If you don't have one, they can be purchased from a salvage yard for a reasonable price. Or you can purchase an automobile "heater core" from just about any auto parts store very inexpensively. On the race version of the Yerbi we would suggest mounting radiator in upper cowl due to that area sustaining the least crash damage. Result? A very fast, liquid cooled 50GP racer, with plenty of room for additional horsepower. Street Package Includes: NEW Derbi GPR Engine Motor Mounts for YSR CDI and Ignition Coil Clutch Cable  Shift Lever Wiring Harness Regulator/Rectifier  Starter Relay for electric start  YSR Wiring Diagram Derbi Wiring Diagram Many of you street riding YSRs already have a pipe and 24mm carb. The pipe for the YSR can be easlily adapted for the Derbi, or we can supply the pipe. (The YSR pipe works extremley well when adapted to the Derbi engine) The 24mm carb bolts right on. You will need a radiator. If you don't have one, they can be purchased from a salvage yard for a reasonable price. Or you can purchase an automobile "heater core" from just about any auto parts store very inexpensively. On the street version of the Yerbi we would suggest mounting radiator on the side of the frame or in front of the engine as long as the front wheel clears it. How hard is this to do? About a 5 on a scale of 10. Motor mounts are already made, so you just bolt it in where the original YSR was. The rest is more time consuming than difficult. Result? A very fast, liquid cooled, 12volt, electric start, 50GP road going racer, with plenty of room for additional horsepower, projector beam headlights, LED stop and turn signals and whatever elst your imagination can conceive! Please note: we will NOT answer Yerbi questions via e-mail. If you have questions, please call 831.484.1921 m-f 9AM-5PM Pacific