TRIUMPH BONNEVILLE T120

1200cc Petrol Class 2

#454 of 5426 overall #29 of 175 TRIUMPHs #85 of 465 cruiser bikes

92.1%

first-time pass rate

3.0%

failed outright

4,316

median miles at test

724

MOT tests, 2005–2025

Pass rate over time

first-time pass rate by test year · 2024–2025

The BONNEVILLE T120's first-time pass rate has risen 3.5 points since 2024, 89.8% to 93.3%.

What fails on a BONNEVILLE T120

failure defects by component group · advisories excluded

Component group	Defects	% of defects	vs all bikes
lamps and reflectors	15	36.6	0.9×
steering and suspension	6	14.6	0.2×
tyres	4	9.8	0.8×
lighting and signalling	4	9.8	0.1×
Identification of the vehicle	3	7.3	1.8×
suspension	2	4.9	0.4×
steering	2	4.9	0.7×
brakes	2	4.9	0.1×
structure and attachments	2	4.9	0.4×
audible warning (Horn)	1	2.4	0.8×

Defects recorded against failed normal tests, 2005–2025, grouped by DVSA inspection section. One test can record multiple defects. "vs all bikes" is how often this model's tests record a defect in the group, as a multiple of the all-bike rate.

How rivals compare

same type, similar capacity, high test volume

On first-time pass rate the BONNEVILLE T120 beats 4 of its 4 closest rivals (TRIUMPH BONNEVILLE, TRIUMPH THUNDERBIRD, HARLEY-DAVIDSON XLH 883).

TRIUMPH BONNEVILLE 89.0% pass · 195k tests TRIUMPH THUNDERBIRD 87.8% pass · 56.3k tests HARLEY-DAVIDSON XLH 883 87.4% pass · 41.2k tests HARLEY-DAVIDSON FLSTF 88.9% pass · 30.1k tests

Rivals share this bike's type and sit within ±30% of its engine capacity, ≥ 5,000 tests. Card colour = better/worse first-time pass rate than the BONNEVILLE T120.

Pass rate by registration year

how each model-year cohort fares · registration year from first use date

Best year to buy used: 1970 (96.6% pass). Weakest: 2021 (89.7%).

First-time pass rate by the year each bike was first registered (cohorts with ≥ 50 tests). Older cohorts are survivors: the worst examples have already left the road, which tends to lift the earliest years.

TRIUMPH BONNEVILLE T120 FAQ

answers computed from the data above · terms in the glossary

Is the TRIUMPH BONNEVILLE T120 reliable?

The TRIUMPH BONNEVILLE T120 is more reliable than average for its class: 92.1% of its 724 MOT tests (2005–2025) passed first time, against a class average of 84.9%. That ranks it #454 of 5426 models.

What does a BONNEVILLE T120 fail its MOT on most?

lamps and reflectors — 37% of all defects recorded against failed BONNEVILLE T120 tests.

What is the best year of BONNEVILLE T120 to buy used?

By first-time pass rate, 1970-registered examples do best (96.6%) and 2021 worst (89.7%). Condition and history still trump the year.