Ariel Arrow vs Yamaha WR250F

The Ariel Arrow passes its MOT first time more often than the Yamaha WR250F: 93.7% vs 78.0%, a 15.7-point lead.

MOT reliability, side by side

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

Metric	Ariel Arrow	Yamaha WR250F
First-time pass rate	93.7%	78.0%
Outright fail rate	1.9%	12.8%
Engine size	250cc	249cc
Rank among all models	#214 of 5428	#3913 of 5428
Median miles at test	19,558	3,018
MOT tests analysed	1,615	10,465
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.

What fails, side by side

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

Component	Ariel Arrow	Yamaha WR250F
Lights & signalling	0.7%	8.2%
Steering & suspension	0.7%	5.1%
Tyres & wheels	0.6%	3.0%
Brakes	0.6%	2.2%
Drive system	0.1%	0.7%
Structure & body	0.3%	0.5%
Fuel & exhaust	0%	0.4%

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	Ariel Arrow	Yamaha WR250F
2011	90.6%	76.7%
2012	93.3%	76.5%
2013	95.1%	75.7%
2014	95.8%	77.9%
2015	95.9%	77.3%
2016	93.4%	78.9%
2017	94.9%	80.3%
2018	93.9%	79.2%

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	Ariel Arrow	Yamaha WR250F
0k-10k miles	95.6%	78.1%
10k-20k miles	95.6%	77.3%
20k-30k miles	91.6%	67.9%

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

Ariel Arrow vs Yamaha WR250F FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Ariel Arrow or the Yamaha WR250F?

The Ariel Arrow passes its MOT first time more often than the Yamaha WR250F: 93.7% vs 78.0%, a 15.7-point lead. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Ariel Arrow fail its MOT on most?

Lights & signalling: 0.7% of Ariel Arrow MOT tests failed on it, then steering & suspension (0.7%).

What does the Yamaha WR250F fail its MOT on most?

Lights & signalling: 8.2% of Yamaha WR250F MOT tests failed on it, then steering & suspension (5.1%).

Which holds up better at high mileage, the Ariel Arrow or the Yamaha WR250F?

At 20k-30k miles the Ariel Arrow passes first time more often: 91.6% for the Ariel Arrow vs 67.9% for the Yamaha WR250F.

ARIEL ARROW 93.7% pass · 1,615 tests YAMAHA WR250F 78.0% pass · 10.5k tests

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