BIKERELIABILITY Reg check
League table/ Buell S1 Lightning/vs Suzuki GSF1200
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Buell S1 Lightning vs Suzuki GSF1200

The Buell S1 Lightning passes its MOT first time more often than the Suzuki GSF1200: 84.1% vs 82.4%, a 1.7-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Buell S1 Lightning Suzuki GSF1200
First-time pass rate 84.1% 82.4%
Outright fail rate 8.6% 8.9%
Vs comparable bikes (age & mileage adjusted) -1.9 pts -1.2 pts
Engine size 1,200cc 1,157cc
Rank among all models #2721 of 5428 #3108 of 5428
Median miles at test 11,469 20,274
MOT tests analysed 560 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 S1 Lightning Suzuki GSF1200
Lights & signalling 5.5% 4.5%
Steering & suspension 3.8% 2.2%
Tyres & wheels 2.0% 2.0%
Brakes 0.9% 2.8%
Fuel & exhaust 1.6% 0.8%
Structure & body 0.9% 0.8%
Drive system 0.4% 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 S1 Lightning Suzuki GSF1200
2006 81.5% 86.2%
2007 84.1% 84.3%
2008 100.0% 82.0%
2009 81.1% 80.3%
2011 73.0% 80.2%
2012 87.9% 80.7%

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 S1 Lightning Suzuki GSF1200
0k-10k miles 85.9% 87.7%
10k-20k miles 83.4% 83.8%
20k-30k miles 81.3% 81.1%

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

Buell S1 Lightning vs Suzuki GSF1200 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Buell S1 Lightning or the Suzuki GSF1200?

The Buell S1 Lightning passes its MOT first time more often than the Suzuki GSF1200: 84.1% vs 82.4%, a 1.7-point lead. Adjusted for age, mileage and test class the two are level (-1.9 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 S1 Lightning fail its MOT on most?

Lights & signalling: 5.5% of Buell S1 Lightning MOT tests failed on it, then steering & suspension (3.8%).

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 S1 Lightning or the Suzuki GSF1200?

They are level: at 20k-30k miles the Buell S1 Lightning passes 81.3% first time and the Suzuki GSF1200 81.1%.

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