Harley-Davidson XL 1200 T Superlow SPORTSTER18 vs Triumph Thunderbird

The Harley-Davidson XL 1200 T Superlow SPORTSTER18 passes its MOT first time more often than the Triumph Thunderbird — 94.1% vs 87.8%, a 6.3-point lead.

MOT reliability, side by side

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

Metric	Harley-Davidson XL 1200 T Superlow SPORTSTER18	Triumph Thunderbird
First-time pass rate	94.1%	87.8%
Outright fail rate	1.7%	6.2%
Median miles at test	6,724	13,106
MOT tests analysed	290	56,312
Most common failure	tyres	brakes

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.

HARLEY-DAVIDSON XL 1200 T SUPERLOW SPORTSTER18 94.1% pass · 290 tests TRIUMPH THUNDERBIRD 87.8% pass · 56.3k tests

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