Hoping that you might be able to help answer a couple of things for me, first, can I put a 69, iron barrel and its piston and head on a 71 bottom end that is a radial head motor? I know that I would have to change the head bolts, but I cant see a reason why it wouldn't work, second, trying to wire up my lights and I have 4 wires, not sure which ones are for the lights and do they go straight to the front and rear lights? I could run them to the switch, then to the lights but wasn't sure if they had to go to a relay or something first, thanks for any help, Mike Carr.
The cylinder and head are a direct swap. You just need to put the longer studs in the cases. I have done it.i think the only difference is the older bikes had an iron connecting rod instead of aluminum.
Thanks, I probably should have said that they are both 125 5a motors, now if I can get the lights wired up I will be a happy camper!