Bsa Rocket 3 vs Triumph Thunderbird

The Bsa Rocket 3 passes its MOT first time more often than the Triumph Thunderbird: 93.4% vs 87.8%, a 5.6-point lead.

MOT reliability, side by side

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

Metric	Bsa Rocket 3	Triumph Thunderbird
First-time pass rate	93.4%	87.8%
Outright fail rate	2.8%	6.2%
Vs comparable bikes (age & mileage adjusted)	+9.2 pts	+2.1 pts
Engine size	750cc	885cc
Rank among all models	#245 of 5428	#1669 of 5428
Median miles at test	12,550	13,106
MOT tests analysed	973	56,312
Most common failure	lighting and signalling	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	Bsa Rocket 3	Triumph Thunderbird
Lights & signalling	1.1%	2.2%
Brakes	0.7%	2.0%
Tyres & wheels	0.9%	1.6%
Steering & suspension	0.9%	1.3%
Fuel & exhaust	0.2%	0.4%
Drive system	0.1%	0.2%
Structure & body	0%	0.3%

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	Bsa Rocket 3	Triumph Thunderbird
2011	91.2%	86.1%
2012	93.8%	88.1%
2013	92.6%	86.5%
2014	95.2%	85.9%
2015	93.8%	88.5%
2016	91.7%	88.2%
2017	94.7%	88.2%
2018	93.5%	87.8%

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	Bsa Rocket 3	Triumph Thunderbird
0k-10k miles	92.9%	90.5%
10k-20k miles	94.4%	87.3%
20k-30k miles	94.4%	85.4%
30k-40k miles	91.1%	84.3%
40k-50k miles	97.6%	83.2%

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

Bsa Rocket 3 vs Triumph Thunderbird FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Bsa Rocket 3 or the Triumph Thunderbird?

The Bsa Rocket 3 passes its MOT first time more often than the Triumph Thunderbird: 93.4% vs 87.8%, a 5.6-point lead. Adjusted for age, mileage and test class, the Bsa Rocket 3 still comes out ahead: +9.2 points vs comparable bikes for the Bsa Rocket 3, +2.1 for the Triumph Thunderbird. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Bsa Rocket 3 fail its MOT on most?

Lights & signalling: 1.1% of Bsa Rocket 3 MOT tests failed on it, then tyres & wheels (0.9%).

What does the Triumph Thunderbird fail its MOT on most?

Lights & signalling: 2.2% of Triumph Thunderbird MOT tests failed on it, then brakes (2.0%).

Which holds up better at high mileage, the Bsa Rocket 3 or the Triumph Thunderbird?

At 40k-50k miles the Bsa Rocket 3 passes first time more often: 97.6% for the Bsa Rocket 3 vs 83.2% for the Triumph Thunderbird.

BSA ROCKET 3 93.4% pass · 973 tests TRIUMPH THUNDERBIRD 87.8% pass · 56.3k tests

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