Vincent Black Shadow vs Harley-Davidson XL

The Vincent Black Shadow passes its MOT first time more often than the Harley-Davidson XL: 94.0% vs 87.9%, a 6.1-point lead.

MOT reliability, side by side

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

Metric	Vincent Black Shadow	Harley-Davidson XL
First-time pass rate	94.0%	87.9%
Outright fail rate	1.2%	5.3%
Engine size	998cc	883cc
Rank among all models	#172 of 5428	#1639 of 5428
Median miles at test	13,531	6,108
MOT tests analysed	822	18,541
Most common failure	lighting and signalling	lamps and reflectors

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	Vincent Black Shadow	Harley-Davidson XL
Lights & signalling	0.7%	3.0%
Steering & suspension	0.2%	0.9%
Brakes	0.2%	0.8%
Structure & body	0%	1.0%
Tyres & wheels	0.1%	0.5%
Drive system	0.1%	0.0%
Fuel & exhaust	0%	0.1%

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	Vincent Black Shadow	Harley-Davidson XL
2006	96.3%	89.7%
2007	91.9%	92.9%
2008	96.0%	93.4%
2009	90.8%	83.6%
2010	93.6%	85.9%
2011	94.7%	91.5%
2012	91.6%	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	Vincent Black Shadow	Harley-Davidson XL
0k-10k miles	94.5%	89.0%
10k-20k miles	94.6%	85.5%
20k-30k miles	92.2%	85.6%
30k-40k miles	93.9%	83.6%
40k-50k miles	90.9%	82.3%

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

Vincent Black Shadow vs Harley-Davidson XL FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Vincent Black Shadow or the Harley-Davidson XL?

The Vincent Black Shadow passes its MOT first time more often than the Harley-Davidson XL: 94.0% vs 87.9%, a 6.1-point lead. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Vincent Black Shadow fail its MOT on most?

Lights & signalling: 0.7% of Vincent Black Shadow MOT tests failed on it, then steering & suspension (0.2%).

What does the Harley-Davidson XL fail its MOT on most?

Lights & signalling: 3.0% of Harley-Davidson XL MOT tests failed on it, then structure & body (1.0%).

Which holds up better at high mileage, the Vincent Black Shadow or the Harley-Davidson XL?

At 40k-50k miles the Vincent Black Shadow passes first time more often: 90.9% for the Vincent Black Shadow vs 82.3% for the Harley-Davidson XL.

VINCENT BLACK SHADOW 94.0% pass · 822 tests HARLEY-DAVIDSON XL 87.9% pass · 18.5k tests

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