SD`s were one of the best in class of their time, my dad and I ran them from 1985 to around 1990, he had a 116 originally and I had a 120 Super, we both moved up to Super injected saws in 1987, still have them and they still run great. Mark, yours looks like a keeper, tough as nails and easy starting saws, a tad heavy by todays standards but we loved them dearly in the late 80`s.