Skip to content

Triumph Junior vs Triumph Unknown: reliability comparison

MOT pass rates, common faults and mileage compared from real UK MOT data.

Triumph Junior
97%
MOT pass rate · 11 vehicles
Triumph Unknown
89%
MOT pass rate · 65,927 vehicles
Verdict: On MOT pass rate the Triumph Junior (97%) and Triumph Unknown (89%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Head to head

Measure Triumph Junior Triumph Unknown
MOT pass rate 97% 89%
MOT failure rate 3% 11%
Faults & advisories per test 0.1 0.6
Dangerous-fault share 0% 2%
Average mileage 1 mi 16,601 mi
Sample size (vehicles) 11 65,927

Most common faults

Triumph Junior

  1. No lights fitted at time of test
  2. no lights fitted at time of test only to be used during daylight hours and not to be used at times of seriously reduced visibility
  3. Daytime use only
  4. Front wheel bearings are slightly rough (2.3.5b)
  5. only to be used during daylight hours and not to be used at times of seriously reduced visibility
  6. rear tyre looks perished.

Triumph Unknown

  1. Exhaust noisy (8.1.1 (a))
  2. Exhaust noisy (7.1.2)
  3. Front Roller brake test indicates slight fluctuation of brake effort (3.3.A1d)
  4. COVID-19 6 MONTH EXTENSION
  5. Rear Tyre worn close to the legal limit (5.2.3 (e))
  6. Steering headbearing has slight free play (2.2.2)

Reliability FAQ

On MOT pass rate the Triumph Junior (97%) and Triumph Unknown (89%) are very close — weigh the individual measures below, and remember condition depends on age, mileage and upkeep.

Full Triumph Junior report Full Triumph Unknown report Most reliable cars

Pass rates are computed over completed (pass/fail) MOT tests. Reliability also depends on age, mileage and upkeep — see each model's page for the full picture.