KTM 125 DUKE 20

125cc Petrol Class 1

#4108 of 5426 overall #189 of 230 KTMs #186 of 205 naked bikes

76.6%

first-time pass rate

14.8%

failed outright

6,621

median miles at test

898

MOT tests, 2005–2025

Pass rate over time

first-time pass rate by test year · 2023–2025

The 125 DUKE 20's first-time pass rate has fallen 1.7 points since 2023, 75.6% to 73.9%.

Pass rate by mileage

how the 125 DUKE 20's first-time pass rate falls with the odometer · class average 73.4%

A low-mileage 125 DUKE 20 passes first time 81.0% of the time; by 20k that's 59.0%.

First-time pass rate by odometer reading at test, 10,000-mile bands for this model. Mileage is the strongest reliability signal. See the full curve.

What fails on a 125 DUKE 20

failure defects by component group · advisories excluded

Component group	Defects	% of defects	vs all bikes
lamps and reflectors	131	39.1	6.0×
brakes	76	22.7	1.4×
structure and attachments	73	21.8	7.8×
tyres	19	5.7	2.8×
suspension	16	4.8	2.1×
steering	11	3.3	2.4×
Identification of the vehicle	7	2.1	3.4×
audible warning (Horn)	1	0.3	0.6×
wheels	1	0.3	1.9×

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 125 DUKE 20 beats 0 of its 1 closest rivals (HONDA CB125F).

HONDA CB125F 81.2% pass · 30.6k 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 125 DUKE 20.

Pass rate by registration year

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

Best year to buy used: 2020 (76.8% pass). Weakest: 2021 (73.1%).

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.

KTM 125 DUKE 20 FAQ

answers computed from the data above · terms in the glossary

Is the KTM 125 DUKE 20 reliable?

The KTM 125 DUKE 20 is more reliable than average for its class: 76.6% of its 898 MOT tests (2005–2025) passed first time, against a class average of 73.4%. That ranks it #4108 of 5426 models.

What does a 125 DUKE 20 fail its MOT on most?

lamps and reflectors — 39% of all defects recorded against failed 125 DUKE 20 tests.

How many miles will a 125 DUKE 20 last?

The median 125 DUKE 20 shows 6,621 miles at test, and examples around 20k miles still pass 59.0% of the time — mileage alone rarely kills one.