BIKERELIABILITY Reg check
League table/ Derbi Senda/vs Piaggio Zip
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

Derbi Senda vs Piaggio Zip

The Piaggio Zip passes its MOT first time more often than the Derbi Senda: 71.3% vs 55.0%, a 16.3-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric Derbi Senda Piaggio Zip
First-time pass rate 55.0% 71.3%
Outright fail rate 33.6% 20.4%
Vs comparable bikes (age & mileage adjusted) -16.8 pts -1.0 pts
Engine size 50cc 49cc
Rank among all models #5339 of 5428 #4631 of 5428
Median miles at test 9,556 8,882
MOT tests analysed 9,050 78,993
Most common failure lighting and signalling lighting and signalling

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 Derbi Senda Piaggio Zip
Lights & signalling 25.0% 11.9%
Steering & suspension 16.7% 9.2%
Brakes 13.2% 6.5%
Tyres & wheels 5.3% 4.0%
Drive system 7.6% 0.0%
Structure & body 5.2% 1.6%
Fuel & exhaust 3.2% 2.5%

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 Derbi Senda Piaggio Zip
2018 50.8% 72.9%
2019 60.0% 73.0%
2020 69.0% 73.1%
2021 62.1% 73.3%
2022 59.9% 74.5%
2023 63.6% 74.1%
2024 65.3% 73.4%
2025 59.6% 76.2%

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 Derbi Senda Piaggio Zip
0k-10k miles 59.3% 75.2%
10k-20k miles 51.4% 66.7%
20k-30k miles 50.5% 64.4%
30k-40k miles 45.9% 64.5%
40k-50k miles 39.1% 65.4%

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

Derbi Senda vs Piaggio Zip FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Derbi Senda or the Piaggio Zip?

The Piaggio Zip passes its MOT first time more often than the Derbi Senda: 71.3% vs 55.0%, a 16.3-point lead. Adjusted for age, mileage and test class, the Piaggio Zip still comes out ahead: -16.8 points vs comparable bikes for the Derbi Senda, -1.0 for the Piaggio Zip. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Derbi Senda fail its MOT on most?

Lights & signalling: 25.0% of Derbi Senda MOT tests failed on it, then steering & suspension (16.7%).

What does the Piaggio Zip fail its MOT on most?

Lights & signalling: 11.9% of Piaggio Zip MOT tests failed on it, then steering & suspension (9.2%).

Which holds up better at high mileage, the Derbi Senda or the Piaggio Zip?

At 40k-50k miles the Piaggio Zip passes first time more often: 39.1% for the Derbi Senda vs 65.4% for the Piaggio Zip.

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