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MOT reliability

Triumph Twenty one

164 vehicles · 856 completed MOT tests analysed
93%
MOT pass rate

Based on 164 Triumph Twenty one vehicles and 856 completed MOT tests, the Triumph Twenty one has an overall 93% pass rate, with an average recorded mileage of 25,297 miles.

164
Vehicles
856
MOT tests
190
Avg miles / year
0.3
Faults per test
1%
Dangerous-fault share

Triumph Twenty one problem areas

Where faults occur most across all Triumph Twenty one MOT tests:

  • Other98%
  • Steering17%
  • Lamps & electrical6%
  • Brakes6%
  • Body & structure1%
  • Emissions & nuisance1%
  • Tyres, wheels & suspension1%

Triumph Twenty one pass rate by age

Age (years)TestsPass rate
1683%
25100%
3580%
45100%
52100%
63100%
73100%
84100%
93100%
10475%
112100%
122100%
131100%
142100%
153100%
162100%
174100%
184100%
19989%
206100%

Fuel types: Petrol (164)

Most common Triumph Twenty one MOT faults

These are the faults and advisories recorded most often across Triumph Twenty one MOT tests:

  1. Front Roller brake test indicates slight fluctuation of brake effort (3.3.A1d) (22 times)
  2. Oil leak (12 times)
  3. Front Tyre worn close to the legal limit (4.1.3(ii)) (8 times)
  4. Rear suspension bush has slight free play (2.4.A2a(i)) (8 times)
  5. Front Wheel has a slightly distorted bead rim. (4.2.2) (8 times)
  6. Rear wheel bearings have slight free play (2.4.A.2c) (8 times)
  7. Wheel alignment slightly misaligned. (2.5.1) (8 times)
  8. Steering headbearing has slight free play (2.2.2) (8 times)
  9. Drive chain slightly loose (6.2.1d) (6 times)
  10. Front wheel bearings are slightly rough (2.3.5b) (6 times)
  11. Rear Roller brake test indicates slight fluctuation of brake effort (3.3.A1d) (6 times)
  12. Steering headbearing has excessive free play (2.2.2) (5 times)
  13. Stop lamp does not illuminate immediately a brake applies (1.3.1a) (5 times)
  14. Rear suspension bearing has slight free play (2.4.A2a(i)) (5 times)
  15. Front wheel bearings have slight free play (2.3.5b) (4 times)

Triumph Twenty one pass rate by registration year

YearVehiclesTestsPass rateAvg mileage
2021 1 2 50% 11,388
2020 1 2 50% —
2018 2 2 100% 1,056
2017 2 4 100% 1,615
2013 2 7 100% 51,677
2009 1 1 100% 41,988
2007 1 2 100% 14
2006 2 14 86% 53,955
2004 1 10 100% 46,606
2003 2 7 100% 23,456
2001 1 8 88% 69,837
1998 1 1 100% 95,228
1996 1 2 100% 3,019
1995 1 1 100% 23,887
1994 1 1 100% 6,454
1992 2 18 89% 21,631
1991 1 7 100% 54,912
1990 2 12 92% 27,950
1988 3 21 90% 20,363
1987 1 9 100% 33,991
1986 1 12 92% 11,695
1985 1 1 0% 39,765
1984 3 19 100% 6,938
1983 2 7 86% 8,946
1982 1 14 86% 52,724
1976 1 9 100% 72,957
1974 1 3 67% 56,353
1967 3 28 93% 31,544
1966 7 44 98% 24,683
1965 9 73 97% 31,543
1964 11 94 90% 40,450
1963 14 90 92% 20,739
1962 13 86 92% 15,167
1961 21 81 91% 23,296
1960 15 56 98% 20,944
1959 8 30 83% 27,119
1958 19 51 94% 15,886
1957 5 27 89% 42,133

Triumph Twenty one reliability FAQ

Across 164 Triumph Twenty one vehicles in our MOT data, 93% pass the MOT (a 7% failure rate), with about 0.3 faults or advisories recorded per test.

The most frequently recorded Triumph Twenty one MOT issues are: Front Roller brake test indicates slight fluctuation of brake effort (3.3.A1d); Oil leak; Front Tyre worn close to the legal limit (4.1.3(ii)).

The typical Triumph Twenty one in our data has covered around 25,297 miles.

Compare the Triumph Twenty one

See how the Triumph Twenty one stacks up against other Triumph models on MOT reliability:

Twenty one vs Toledo Twenty one vs Unknown Twenty one vs 2000 Twenty one vs 1500

Check a specific Triumph Twenty one

Enter a registration to see that exact vehicle's full MOT history, advisories and recurring faults.

See all Triumph models · Learn about common MOT failures · what an MOT checks