Norton 50 vs Yamaha RD350

The Norton 50 passes its MOT first time more often than the Yamaha RD350: 91.5% vs 86.3%, a 5.2-point lead.

MOT reliability, side by side

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

Metric	Norton 50	Yamaha RD350
First-time pass rate	91.5%	86.3%
Outright fail rate	0.8%	6.6%
Engine size	350cc	347cc
Rank among all models	#567 of 5428	#2120 of 5428
Median miles at test	19,595	23,256
MOT tests analysed	365	19,574
Most common failure	lighting and signalling	lighting and signalling

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.

Pass rate by test year

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

Test year	Norton 50	Yamaha RD350
2006	95.0%	79.9%
2007	90.7%	81.2%
2008	91.9%	79.7%
2009	90.3%	80.6%
2011	86.8%	82.2%

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	Norton 50	Yamaha RD350
0k-10k miles	85.7%	88.9%
10k-20k miles	95.1%	87.5%
20k-30k miles	90.6%	85.5%
30k-40k miles	97.7%	85.3%

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

NORTON 50 91.5% pass · 365 tests YAMAHA RD350 86.3% pass · 19.6k tests

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