I took the smallest child cranks that I could find and cut them down and then re drilled and tapped the holes for the cranks, I used a center distance of 100 mm for my 2 1/2 year old daughter. I have a machine shop so this was quite easy to do, however any local machine shop in your area should have no problem doing the same. I would recommend buying the LH & RH taps for the pedals from a bike supplier as these are not common thread sizes to make it easier for the shop. It is important that you have the equipment to hold accurate center distances as well as keep all the holes straight in relationship to centerlines of the crank mounting holes so that there is no wobbling of the pedals.