Norton 850 vs Yamaha FZS600

The Norton 850 passes its MOT first time more often than the Yamaha FZS600: 92.7% vs 82.6%, a 10.1-point lead.

MOT reliability, side by side

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

Metric	Norton 850	Yamaha FZS600
First-time pass rate	92.7%	82.6%
Outright fail rate	1.0%	10.6%
Vs comparable bikes (age & mileage adjusted)	+11.3 pts	-0.8 pts
Engine size	828cc	599cc
Rank among all models	#344 of 5428	#3052 of 5428
Median miles at test	23,840	21,612
MOT tests analysed	287	136,558
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.

Pass rate by mileage

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

Mileage	Norton 850	Yamaha FZS600
0k-10k miles	94.5%	89.6%
10k-20k miles	95.1%	85.5%
20k-30k miles	83.9%	81.4%
30k-40k miles	94.7%	78.7%
50k-60k miles	96.7%	74.7%

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

NORTON 850 92.7% pass · 287 tests YAMAHA FZS600 82.6% pass · 137k tests

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