Buell XB12S vs Suzuki GSF1200

The Buell XB12S passes its MOT first time more often than the Suzuki GSF1200: 86.2% vs 82.4%, a 3.8-point lead.

MOT reliability, side by side

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

Metric	Buell XB12S	Suzuki GSF1200
First-time pass rate	86.2%	82.4%
Outright fail rate	6.7%	8.9%
Vs comparable bikes (age & mileage adjusted)	-0.9 pts	-1.2 pts
Engine size	1,203cc	1,157cc
Rank among all models	#2148 of 5428	#3108 of 5428
Median miles at test	8,538	20,274
MOT tests analysed	5,087	97,637
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.

"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.

What fails, side by side

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

Component	Buell XB12S	Suzuki GSF1200
Lights & signalling	3.7%	4.5%
Brakes	1.1%	2.8%
Steering & suspension	1.5%	2.2%
Tyres & wheels	1.2%	2.0%
Structure & body	0.8%	0.8%
Fuel & exhaust	0.4%	0.8%
Drive system	0.1%	0.6%

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	Buell XB12S	Suzuki GSF1200
2018	91.9%	83.2%
2019	88.3%	82.9%
2020	87.5%	83.4%
2021	89.6%	82.9%
2022	89.6%	83.6%
2023	87.4%	83.8%
2024	90.5%	83.4%
2025	90.6%	84.1%

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	Buell XB12S	Suzuki GSF1200
0k-10k miles	87.9%	87.7%
10k-20k miles	84.2%	83.8%
20k-30k miles	84.8%	81.1%
30k-40k miles	78.5%	78.5%

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

Buell XB12S vs Suzuki GSF1200 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Buell XB12S or the Suzuki GSF1200?

The Buell XB12S passes its MOT first time more often than the Suzuki GSF1200: 86.2% vs 82.4%, a 3.8-point lead. Adjusted for age, mileage and test class the two are level (-0.9 vs -1.2 points against comparable bikes), so the raw gap is mostly down to how old and how used each fleet is. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Buell XB12S fail its MOT on most?

Lights & signalling: 3.7% of Buell XB12S MOT tests failed on it, then steering & suspension (1.5%).

What does the Suzuki GSF1200 fail its MOT on most?

Lights & signalling: 4.5% of Suzuki GSF1200 MOT tests failed on it, then brakes (2.8%).

Which holds up better at high mileage, the Buell XB12S or the Suzuki GSF1200?

They are level: at 30k-40k miles the Buell XB12S passes 78.5% first time and the Suzuki GSF1200 78.5%.

BUELL XB12S 86.2% pass · 5,087 tests SUZUKI GSF1200 82.4% pass · 97.6k tests

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