The 1927 Isle of Man Tourist Trophy saw more changes occur with a fatal accident during practice to Archie Birkin, a brother to Tim Birkin of the Bentley Boys fame. The corner in Kirk Michael where the accident occurred was renamed Birkins Bend and from 1928 practice sessions were held on closed-roads. In the 1927 Junior TT Race the retirement of Wal Handley on the last-lap handed the victory to Freddie W Dixon, riding a HRD motorcycle, winning at an average speed of 67.19mi/h.
In the 1927 Lightweight TT Race, Wal Handley won the 7 lap race in 4 hours 10 minutes and 23 seconds, at an average speed of 63.3mi/h. A slipping clutch for Stanley Woods in the 1927 Senior TT Race, riding a new over-head camshaft Norton, allowed teammate Alec Bennett to win at an average speed of 68.41mi/h.
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | 68.41mi/h | 3.51.42 | |||
| 2 | 66.02 | 4.00.04 | |||
| 3 | 65.75 | 4.01.03 | |||
| 4 | J W Shaw | Norton | 64.83 | 4.04.28 | |
| 5 | 64.72 | 4.04.52 | |||
| 6 | 64.32 | 4.06.26 | |||
| 7 | Oliver Langton | New Hudson | 64.04 | 4.07.29 | |
| 8 | Charlie Dodson | Sunbeam | 63.77 | 4.08.23 | |
| 9 | George Rowley | 63.74 | 4.08.40 | ||
| 10 | Walter Braidwood | 62.94 | 4.11.50 |
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | Freddie Dixon | 67.19mi/h | 3.55.54 | ||
| 2 | Harold Willis | 64.78 | 4.06.39 | ||
| 3 | AJS | 64.33 | 4.08.22 | ||
| 4 | George Reynard | 64.32 | 4.08.24 | ||
| 5 |  Paddy Johnston | 63.81 | 4.10.21 | ||
| 6 | Edwin Twemlow | 62.81 | 4.12.19 | ||
| 7 | Cecil Barrow | Royal Enfield | 62.4 | 4.15.23 | |
| 8 | Len Cohen | AJS | 61.3 | 4.18.34 | |
| 9 | Sax Pearce | 60.57 | 4.21.39 | ||
| 10 | George Himing | Zenith | 60.39 | 4.22.27 |
| Rank | Rider | Team | Speed | Time | |
|---|---|---|---|---|---|
| 1 | 63.3 mph | 4.10.22 | |||
| 2 | 61.2 | 4.18.52 | |||
| 3 | 61.1 | 4.19.24 | |||
| 4 | Crabtree | 58.15 | 4.32.32 | ||
| 5 | Moto Guzzi | 57.60 | 4.35.08 | ||
| 6 | F L Hall | 57.44 | 4.35.56 | ||
| 7 | Cecil Barrow | Royal Enfield | 57.35 | 4.36.21 | |
| 8 | Sid Gleave | DOT | 57.22 | 4.37.01 | |
| 9 | Geoff Davison | Rex Acme | 56.72 | 4.39.26 | |
| 10 | L Higson | Montgomery | 56.41 | 4.41.00 |