The unit single is the replacement for the pre-unit single. That cleared things up much?
Unit singles (Unit Construction Singles) are from the days when BSA and Triumph were operated on a sort of collective basis, sharing a lot of parts, mainly the engines. Good examples are BSA Starfires, Triumph Trophies, BSA Bantams. Most 250 - 500 cc bikes from the 60's and early seventies. The complete list of unit singles is
- From Triumph - TR25W (like mine), T25T, T25SS, TR5MX
- From BSA - C15, B40, B25, B44, B50
The one to get if you can is the B44 Victor Special (500cc). Later bikes tended to get less con-rod issues.
|