There were 2 models of Honda PC50 (in England, in Holland there were several different machines with different forks).
The first model introduced in 1968 was an Overhead Camshaft Engined model, this has an aluminium cylinder head, and the exhaust comes out on the left hand side of the cylinder head and goes across to the right hand side of the machine, this machine was produced until 1970 when it was replaced by the PC50K1 model which had an Overhead valve engine with the valves operated by Pushrods, this machine has a cast iron cylinder head, and the exhaust comes out of the right hand side of the cylinder head and exits on the right hand side of the machine, this machine was produced up until about 1977.
On the early PC50 machine the rear sprocket is held on with a circlip, on the later PC50K1 machine it is held with three 8mm nuts.
The early machine did not have a very strong engine and not many survived.
I have one of each of the PC50s (I have been to France on each of them for the Sars Poteries rally) and I also have two P50s with the engine in the rear wheel.
Check out the National Autocycle and Cyclemotor Website on
I hope this has been of some help