Harley-Davidson Street XG 750 17 vs Triumph Thunderbird

The Harley-Davidson Street XG 750 17 passes its MOT first time more often than the Triumph Thunderbird: 89.3% vs 87.8%, a 1.5-point lead.

MOT reliability, side by side

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

Metric	Harley-Davidson Street XG 750 17	Triumph Thunderbird
First-time pass rate	89.3%	87.8%
Outright fail rate	4.6%	6.2%
Median miles at test	4,411	13,106
MOT tests analysed	850	56,312
Most common failure	lamps and reflectors	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 STREET XG 750 17 89.3% pass · 850 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.