BIKERELIABILITY Reg check
League table/ Ducati Monster/vs Triumph Street Triple
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Ducati Monster vs Triumph Street Triple

The Triumph Street Triple passes its MOT first time more often than the Ducati Monster: 87.7% vs 83.9%, a 3.8-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Ducati Monster Triumph Street Triple
First-time pass rate 83.9% 87.7%
Outright fail rate 8.6% 5.9%
Vs comparable bikes (age & mileage adjusted) -2.1 pts +1.3 pts
Engine size 803cc 675cc
Rank among all models #2767 of 5428 #1695 of 5428
Median miles at test 11,140 11,189
MOT tests analysed 8,991 37,699
Most common failure lighting and signalling brakes

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 Ducati Monster Triumph Street Triple
Lights & signalling 4.7% 2.6%
Brakes 2.4% 1.6%
Steering & suspension 2.1% 1.2%
Tyres & wheels 1.6% 1.2%
Structure & body 0.5% 0.7%
Drive system 0.7% 0.2%
Fuel & exhaust 0.4% 0.1%

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 Ducati Monster Triumph Street Triple
2018 85.4% 87.8%
2019 86.9% 87.9%
2020 86.3% 89.6%
2021 87.4% 87.2%
2022 85.9% 87.3%
2023 85.6% 87.5%
2024 90.9% 88.0%
2025 86.4% 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 Ducati Monster Triumph Street Triple
0k-10k miles 87.3% 91.3%
10k-20k miles 82.4% 86.7%
20k-30k miles 79.7% 82.7%
30k-40k miles 78.9% 79.9%
40k-50k miles 77.8% 74.6%
50k-60k miles 78.1% 75.6%

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

Ducati Monster vs Triumph Street Triple FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Ducati Monster or the Triumph Street Triple?

The Triumph Street Triple passes its MOT first time more often than the Ducati Monster: 87.7% vs 83.9%, a 3.8-point lead. Adjusted for age, mileage and test class, the Triumph Street Triple still comes out ahead: -2.1 points vs comparable bikes for the Ducati Monster, +1.3 for the Triumph Street Triple. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Ducati Monster fail its MOT on most?

Lights & signalling: 4.7% of Ducati Monster MOT tests failed on it, then brakes (2.4%).

What does the Triumph Street Triple fail its MOT on most?

Lights & signalling: 2.6% of Triumph Street Triple MOT tests failed on it, then brakes (1.6%).

Which holds up better at high mileage, the Ducati Monster or the Triumph Street Triple?

At 50k-60k miles the Ducati Monster passes first time more often: 78.1% for the Ducati Monster vs 75.6% for the Triumph Street Triple.

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