BIKERELIABILITY
MOT DATA · GREAT BRITAIN · 2005–2025
League table/ BETTER/BT 125-20
Model report · 2005–2025

BETTER BT 125-20

125cc Petrol Class 1
#5333 of 5426 overall #1 of 1 BETTERs #691 of 734 commuter bikes
55.3%
first-time pass rate
30.1%
failed outright
4,245
median miles at test
976
MOT tests, 2005–2025

Pass rate over time

first-time pass rate by test year · 2008–2016

The BT 125-20's first-time pass rate has fallen 17.1 points since 2008, 65.9% to 48.8%.

39%55%71%2008: 65.9% pass (44 tests)2009: 54.9% pass (175 tests)2010: 59.3% pass (140 tests)2011: 58.9% pass (129 tests)2012: 48.3% pass (120 tests)2013: 52.9% pass (102 tests)2014: 44.4% pass (81 tests)2015: 52.8% pass (53 tests)2016: 48.8% pass (43 tests)20082016

What fails on a BT 125-20

failure defects by component group · advisories excluded
Component group Share of defects Defects % of defects vs all bikes
lighting and signalling
360 34.7 4.5×
steering and suspension
214 20.6 4.4×
brakes
147 14.2 2.6×
body and structure
93 9 13.2×
drive system
75 7.2 8.1×
tyres and wheels
69 6.6 3.3×
fuel and exhaust
29 2.8 3.5×
lamps and reflectors
25 2.4 0.8×
structure and attachments
14 1.3 1.2×
reg plates and vin
12 1.2 1.4×

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 BT 125-20 beats 0 of its 4 closest rivals (YAMAHA YBR 125, HONDA CG125, HONDA CBF125).

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 BT 125-20.

Pass rate by registration year

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

Best year to buy used: 2005 (58.4% pass). Weakest: 2006 (53.7%).

53%56%59%2005: 58.4% pass (327 tests)2006: 53.7% pass (646 tests)20052006

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.

BETTER BT 125-20 FAQ

answers computed from the data above · terms in the glossary

Is the BETTER BT 125-20 reliable?

The BETTER BT 125-20 is less reliable than average for its class: 55.3% of its 976 MOT tests (2005–2025) passed first time, against a class average of 73.4%. That ranks it #5333 of 5426 models.

What does a BT 125-20 fail its MOT on most?

lighting and signalling — 35% of all defects recorded against failed BT 125-20 tests.