YAMAHA DT175

171cc Petrol Class 1

#2984 of 5426 overall #172 of 409 YAMAHAs #1887 of 2787 other bikes

82.9%

first-time pass rate

8.7%

failed outright

12,008

median miles at test

2,702

MOT tests, 2005–2025

Pass rate over time

first-time pass rate by test year · 2005–2022

The DT175's first-time pass rate has risen 3.6 points since 2005, 84.8% to 88.4%.

Pass rate by mileage

how the DT175's first-time pass rate falls with the odometer · class average 73.4%

A low-mileage DT175 passes first time 82.5% of the time; by 40k that's 73.3%.

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 DT175

failure defects by component group · advisories excluded

Component group	Defects	% of defects	vs all bikes
lighting and signalling	337	51	1.4×
steering and suspension	113	17.1	0.9×
tyres and wheels	64	9.7	0.8×
lamps and reflectors	43	6.5	0.5×
brakes	34	5.1	0.2×
fuel and exhaust	23	3.5	1.0×
reg plates and vin	17	2.6	1.0×
drive system	15	2.3	0.7×
audible warning (Horn)	9	1.4	1.8×
suspension	6	0.9	0.3×

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 DT175 beats 0 of its 1 closest rivals (BSA BANTAM).

BSA BANTAM 88.7% pass · 7,201 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 DT175.

Pass rate by registration year

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

Best year to buy used: 1975 (89.2% pass). Weakest: 1984 (74.4%).

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.

YAMAHA DT175 FAQ

answers computed from the data above · terms in the glossary

Is the YAMAHA DT175 reliable?

The YAMAHA DT175 is more reliable than average for its class: 82.9% of its 2,702 MOT tests (2005–2025) passed first time, against a class average of 73.4%. That ranks it #2984 of 5426 models.

What does a DT175 fail its MOT on most?

lighting and signalling — 51% of all defects recorded against failed DT175 tests.

What is the best year of DT175 to buy used?

By first-time pass rate, 1975-registered examples do best (89.2%) and 1984 worst (74.4%). Condition and history still trump the year.

How many miles will a DT175 last?

The median DT175 shows 12,008 miles at test, and examples around 40k miles still pass 73.3% of the time — mileage alone rarely kills one.