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League table/ NORTON/BIG 4
Model report · 2005–2025

NORTON BIG 4

600cc Petrol Class 2
98.0%
first-time pass rate
1.0%
failed outright
7,104
median miles at test
101
MOT tests, 2005–2025

The pass rate is the MOT first-time pass: a roadworthiness check of the items an MOT covers (brakes, lights, tyres, steering, structure, emissions), not a full mechanical inspection of engine or gearbox internals. It is a reliability signal, not a complete measure of mechanical reliability. What this measures.

What fails on a BIG 4

failure defects by component group · advisories excluded
Component group Share of defects Defects % of defects
lighting and signalling
1 100

Defects recorded against failed normal tests, 2005–2025, grouped by DVSA inspection section. One test can record multiple defects.

How rivals compare

same type, similar capacity, high test volume

On first-time pass rate the BIG 4 beats 4 of its 4 closest rivals (KAWASAKI ZX-6R, SUZUKI GSF600, YAMAHA FZS600).

KAWASAKI ZX-6R 78.1% pass · 174k tests Compare head-to-head →
SUZUKI GSF600 77.3% pass · 143k tests Compare head-to-head →
YAMAHA FZS600 82.6% pass · 137k tests Compare head-to-head →
SUZUKI SV650S 80.6% pass · 84.6k tests Compare head-to-head →

Rivals share this bike's type and sit within ±30% of its engine capacity, ≥ 5,000 tests. Card colour = better/worse first-time pass rate than the BIG 4.

Compare with any bike

rival not listed above? pick any model to see it head-to-head with the Big 4

More NORTON models

other NORTON bikes ranked by MOT pass rate
NORTON COMMANDO 90.8% pass · 12.3k tests
NORTON DOMINATOR 92.6% pass · 3,807 tests
NORTON ES2 91.3% pass · 2,223 tests
NORTON COMMANDER 91.6% pass · 2,094 tests
NORTON TRITON 92.1% pass · 1,496 tests
NORTON ATLAS 92.5% pass · 1,153 tests

See all NORTON models →

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