ORIGINAL: edge_fanatic
I think the main difference is that the head of the 50 is bored out more than the 44, making the 50 slightly lighter, and slightly more powerful...
the two are very different! the 44 has a 12mm crank while the 50's crank is 15mm.......and i do believe that the 50 is a bit heavier.
the 44 was echo's attempt to get a bit more power from a their 39cc engine while the 50 is a totally different design that offers not only a lot more power but also more strength
dave