Triumph 21
Real ownership data from 95 UK 21 motorcycles — mileage, MOT pass rates and the faults that actually come up, taken from DVSA test records rather than opinion.
Most common 21 problems
Ranked by how often each fault appears in this model's MOT history.
| Fault | Severity | Share of faults |
|---|---|---|
| Tyres | fail | 9% |
| Lights and indicators | fail | 7.2% |
| Other | user entered | 5.9% |
| Brakes | fail | 4.5% |
| Fluid leaks | user entered | 2.7% |
| Controls and cables | fail | 2.3% |
| Wheels | fail | 1.8% |
| Electrical | fail | 1.8% |
Advisories (wear noted but not failed) are excluded above; the most common is brakes.
21 mileage and reliability by year
Use this to judge whether a specific bike is high or low mileage for its age.
| Year | Examples | Median mileage | Miles/year | First-time pass |
|---|---|---|---|---|
| 1963 | 5 | 44,253 mi | 131 | 95.12% |
| 1962 | 13 | 12,565 mi | 192 | 90.67% |
| 1961 | 7 | 6,847 mi | 59 | 91.67% |
| 1960 | 12 | 30,882 mi | 102 | 91.67% |
| 1959 | 5 | 1,605 mi | 11 | 94.44% |
| 1958 | 12 | 4,605 mi | 81 | 97.44% |
| 1957 | 6 | 7,432 mi | 504 | 100% |
21 questions, answered with data
What are the most common problems with the Triumph 21?
Across 95 UK examples, the most frequently recorded MOT faults are tyres (9% of all recorded faults), lights and indicators (7.2% of all recorded faults), other (5.9% of all recorded faults).
What is average mileage for a Triumph 21?
The median Triumph 21 in the UK has covered 12,199 miles, and typically rides about 85 miles a year. Half of all examples fall between 2,079 and 32,979 miles.
Is the Triumph 21 reliable?
94.31% of Triumph 21 MOT tests are passed first time, with an average of 0.47 faults recorded per test. This is measured from DVSA MOT records, not owner opinion.
Based on DVSA MOT test records for 95 Triumph 21 motorcycles registered in Great Britain and Northern Ireland. Contains public sector information licensed under the Open Government Licence v3.0.