The Ultra-Lightweight TT was a motorcycle road race that took place during the Isle of Man TT festival, an annual event at the end of May and beginning of June. Between 1951 and 1974 this race was part of the Grand Prix motorcycle racing season at world-level, representing the British round. The Ultra-Lightweight TT and the Lightweight TT races were both dropped from the 2005 Isle of Man TT race calendar due to lack of entries, but were later reinstated to the 2008 and 2009 TT race schedules held on the 4.25miles Billown Circuit.[1]
The 1924 Isle of Man TT was the first race for Ultra-Lightweight motorcycles not exceeding 175 cc engine capacity, won by Jack Porter, on a New Imperial at an average speed of 51.21mi/h for three laps of the Snaefell mountain course. The Ultra-Lightweight TT race was re-introduced for the 1951 Isle of Man TT race for motorcycles not exceeding 125 cc engine capacity until dropped from the TT race meeting in 1974. The Ultra-Lightweight race was re-introduced for the 1989 TT races, again for motorcycles not exceeding 125 cc engine capacity and was part of the TT Festival until 2004.
The lap record for the Ultra-Lightweight TT is 19 minutes and 18.2 seconds[2] at an average speed of 110.52mi/h set by Chris Palmer during the 2004 Ultra-Lightweight 125 cc TT Race.
| Year | Rider | Motorcycle | Average Speed | |
|---|---|---|---|---|
| 1962 | Ernst Degner | Suzuki | 75.12 mph | |
| 1963 |  Mitsuo Itoh | Suzuki | 78.81 mph | |
| 1964 |  Hugh Anderson | Suzuki | 80.64 mph | |
| 1965 |  Luigi Taveri | Honda | 79.66 mph | |
| 1966 | Ralph Bryans | Honda | 85.66 mph | |
| 1967 | Stuart Graham | Suzuki | 82.89 mph | |
| 1968 |  Barry Smith | Derbi | 72.90 mph |
| Rider | Wins | |
|---|---|---|
| 4 | ||
| Robert Dunlop, Chris Palmer | 3 | |
| Chas Mortimer, Phil Read, Tarquinio Provini*, Luigi Taveri | 2 | |
| Hugh Anderson, M.Baldwin, Dieter Braun, Les Graham, Rupert Hollaus*, Wal Handley, C.Horton, Bill Ivy, Cromie McCandless, Mike Hailwood, Jack Porter, Tommy Robb, Cecil Sandford, Dave Simmonds | 1 |
| Marque | Wins | |
|---|---|---|
| 20 | ||
| Yamaha | 8 | |
| MV Agusta | 7 | |
| Mondial, Suzuki | 2 | |
| Kawasaki, New Imperial, NSU, Rex-Acme | 1 |
Clive Horton