Indian Motorcycle Roadmaster vs Triumph Rocket Iii

The Indian Motorcycle Roadmaster passes its MOT first time more often than the Triumph Rocket Iii: 96.6% vs 88.3%, a 8.3-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025

Metric	Indian Motorcycle Roadmaster	Triumph Rocket Iii
First-time pass rate	96.6%	88.3%
Outright fail rate	2.3%	6.1%
Vs comparable bikes (age & mileage adjusted)	+9.6 pts	+2.7 pts
Engine size	1,811cc	2,294cc
Rank among all models	#15 of 5428	#1505 of 5428
Median miles at test	11,310	13,110
MOT tests analysed	641	15,488
Most common failure	lamps and reflectors	brakes

First-time outcomes on normal tests, 2005–2025. "Most common failure" is the component group with the most recorded defects on failed tests. Read pass rates against test counts: a smaller sample is noisier. Source: DVSA anonymised MOT results.

"Vs comparable bikes" is the first-time pass rate minus the rate expected for each bike's own mix of age, mileage and test class, in percentage points: positive means better than comparable bikes. How this works.

What fails, side by side

share of each bike's MOT tests that failed on the component · lower is better

Component	Indian Motorcycle Roadmaster	Triumph Rocket Iii
Lights & signalling	0.6%	2.3%
Tyres & wheels	0.5%	2.0%
Brakes	0.6%	1.8%
Steering & suspension	0.5%	0.7%
Fuel & exhaust	0%	0.6%
Structure & body	0.3%	0.2%

A test that fails on two components counts once in each. Component links go to the bikes most likely to fail on it.

Pass rate by test year

first-time MOT pass rate in each calendar year both bikes were tested

Test year	Indian Motorcycle Roadmaster	Triumph Rocket Iii
2020	96.3%	88.4%
2021	100.0%	88.5%
2022	96.4%	88.7%
2023	94.5%	89.3%
2024	96.9%	90.7%
2025	97.3%	88.3%

Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.

Pass rate by mileage

first-time MOT pass rate by miles on the clock at test

Mileage	Indian Motorcycle Roadmaster	Triumph Rocket Iii
0k-10k miles	98.1%	89.2%
10k-20k miles	95.2%	88.6%
20k-30k miles	96.5%	87.7%

Bands with fewer than 30 tests for either bike are left out.

Indian Motorcycle Roadmaster vs Triumph Rocket Iii FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Indian Motorcycle Roadmaster or the Triumph Rocket Iii?

The Indian Motorcycle Roadmaster passes its MOT first time more often than the Triumph Rocket Iii: 96.6% vs 88.3%, a 8.3-point lead. Adjusted for age, mileage and test class, the Indian Motorcycle Roadmaster still comes out ahead: +9.6 points vs comparable bikes for the Indian Motorcycle Roadmaster, +2.7 for the Triumph Rocket Iii. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Indian Motorcycle Roadmaster fail its MOT on most?

Lights & signalling: 0.6% of Indian Motorcycle Roadmaster MOT tests failed on it, then brakes (0.6%).

What does the Triumph Rocket Iii fail its MOT on most?

Lights & signalling: 2.3% of Triumph Rocket Iii MOT tests failed on it, then tyres & wheels (2.0%).

Which holds up better at high mileage, the Indian Motorcycle Roadmaster or the Triumph Rocket Iii?

At 20k-30k miles the Indian Motorcycle Roadmaster passes first time more often: 96.5% for the Indian Motorcycle Roadmaster vs 87.7% for the Triumph Rocket Iii.

INDIAN MOTORCYCLE ROADMASTER 96.6% pass · 641 tests TRIUMPH ROCKET III 88.3% pass · 15.5k tests

See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.