BIKERELIABILITY Reg check
League table/ KTM 390 Duke 17/vs Honda CB400
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

KTM 390 Duke 17 vs Honda CB400

The KTM 390 Duke 17 passes its MOT first time more often than the Honda CB400: 87.0% vs 80.9%, a 6.1-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric KTM 390 Duke 17 Honda CB400
First-time pass rate 87.0% 80.9%
Outright fail rate 6.5% 11.0%
Vs comparable bikes (age & mileage adjusted) -2.4 pts -1.6 pts
Engine size 373cc 400cc
Rank among all models #1910 of 5428 #3398 of 5428
Median miles at test 4,650 30,796
MOT tests analysed 2,885 9,072
Most common failure lamps and reflectors steering and suspension

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.

"Vs comparable bikes" is the first-time pass rate minus the rate expected for each bike's own mix of age, mileage and test class, in percentage points: positive means better than comparable bikes. How this works.

What fails, side by side

share of each bike's MOT tests that failed on the component · lower is better
Component KTM 390 Duke 17 Honda CB400
Lights & signalling 2.7% 4.5%
Brakes 2.3% 4.0%
Steering & suspension 1.2% 4.9%
Tyres & wheels 1.2% 2.3%
Structure & body 1.5% 0.6%
Drive system 0% 1.1%
Fuel & exhaust 0% 0.6%

A test that fails on two components counts once in each. Component links go to the bikes most likely to fail on it.

Pass rate by test year

first-time MOT pass rate in each calendar year both bikes were tested
Test year KTM 390 Duke 17 Honda CB400
2020 91.8% 87.6%
2021 89.2% 86.7%
2022 86.2% 85.8%
2023 85.6% 90.4%
2024 85.9% 79.1%
2025 84.1% 86.4%

Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.

Pass rate by mileage

first-time MOT pass rate by miles on the clock at test
Mileage KTM 390 Duke 17 Honda CB400
0k-10k miles 87.8% 80.9%
10k-20k miles 81.5% 83.0%
20k-30k miles 67.4% 83.3%

Bands with fewer than 30 tests for either bike are left out.

KTM 390 Duke 17 vs Honda CB400 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the KTM 390 Duke 17 or the Honda CB400?

The KTM 390 Duke 17 passes its MOT first time more often than the Honda CB400: 87.0% vs 80.9%, a 6.1-point lead. Adjusted for age, mileage and test class the two are level (-2.4 vs -1.6 points against comparable bikes), so the raw gap is mostly down to how old and how used each fleet is. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the KTM 390 Duke 17 fail its MOT on most?

Lights & signalling: 2.7% of KTM 390 Duke 17 MOT tests failed on it, then brakes (2.3%).

What does the Honda CB400 fail its MOT on most?

Steering & suspension: 4.9% of Honda CB400 MOT tests failed on it, then lights & signalling (4.5%).

Which holds up better at high mileage, the KTM 390 Duke 17 or the Honda CB400?

At 20k-30k miles the Honda CB400 passes first time more often: 67.4% for the KTM 390 Duke 17 vs 83.3% for the Honda CB400.

See each bike's full report (trend, mileage curve, failure breakdown and rivals) on its own page.