BIKERELIABILITY Reg check
League table/ Triumph Tiger 800/vs Yamaha XT 660 Z Tenere
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Triumph Tiger 800 vs Yamaha XT 660 Z Tenere

The Triumph Tiger 800 passes its MOT first time more often than the Yamaha XT 660 Z Tenere: 91.6% vs 87.4%, a 4.2-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Triumph Tiger 800 Yamaha XT 660 Z Tenere
First-time pass rate 91.6% 87.4%
Outright fail rate 4.8% 6.0%
Vs comparable bikes (age & mileage adjusted) +6.5 pts +2.4 pts
Engine size 800cc 660cc
Rank among all models #546 of 5428 #1787 of 5428
Median miles at test 16,027 16,356
MOT tests analysed 6,797 5,654
Most common failure brakes lamps and reflectors

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 Triumph Tiger 800 Yamaha XT 660 Z Tenere
Lights & signalling 1.1% 2.6%
Brakes 1.8% 1.7%
Steering & suspension 1.2% 1.6%
Tyres & wheels 1.1% 1.0%
Structure & body 0.5% 0.8%
Drive system 0.2% 0.4%
Fuel & exhaust 0.0% 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 Triumph Tiger 800 Yamaha XT 660 Z Tenere
2018 90.7% 85.0%
2019 90.5% 86.4%
2020 92.6% 85.6%
2021 90.9% 88.4%
2022 92.8% 83.5%
2023 90.2% 86.6%
2024 92.1% 84.5%
2025 89.4% 84.4%

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 Triumph Tiger 800 Yamaha XT 660 Z Tenere
0k-10k miles 94.4% 93.0%
10k-20k miles 91.9% 87.9%
20k-30k miles 90.2% 84.7%
30k-40k miles 89.0% 82.6%
40k-50k miles 86.5% 77.9%
50k-60k miles 86.5% 85.3%

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

Triumph Tiger 800 vs Yamaha XT 660 Z Tenere FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Triumph Tiger 800 or the Yamaha XT 660 Z Tenere?

The Triumph Tiger 800 passes its MOT first time more often than the Yamaha XT 660 Z Tenere: 91.6% vs 87.4%, a 4.2-point lead. Adjusted for age, mileage and test class, the Triumph Tiger 800 still comes out ahead: +6.5 points vs comparable bikes for the Triumph Tiger 800, +2.4 for the Yamaha XT 660 Z Tenere. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Triumph Tiger 800 fail its MOT on most?

Brakes: 1.8% of Triumph Tiger 800 MOT tests failed on it, then steering & suspension (1.2%).

What does the Yamaha XT 660 Z Tenere fail its MOT on most?

Lights & signalling: 2.6% of Yamaha XT 660 Z Tenere MOT tests failed on it, then brakes (1.7%).

Which holds up better at high mileage, the Triumph Tiger 800 or the Yamaha XT 660 Z Tenere?

At 50k-60k miles the Triumph Tiger 800 passes first time more often: 86.5% for the Triumph Tiger 800 vs 85.3% for the Yamaha XT 660 Z Tenere.

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