BIKERELIABILITY Reg check
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

SYM AD05W Jet 4 50 vs Piaggio Zip

The Piaggio Zip passes its MOT first time more often than the SYM AD05W Jet 4 50: 71.3% vs 71.2%, a 0.1-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric SYM AD05W Jet 4 50 Piaggio Zip
First-time pass rate 71.2% 71.3%
Outright fail rate 21.7% 20.4%
Vs comparable bikes (age & mileage adjusted) -0.5 pts -1.0 pts
Engine size 49cc 49cc
Rank among all models #4640 of 5428 #4631 of 5428
Median miles at test 10,168 8,882
MOT tests analysed 819 78,993
Most common failure brakes 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 SYM AD05W Jet 4 50 Piaggio Zip
Lights & signalling 9.2% 11.9%
Steering & suspension 9.0% 9.2%
Brakes 8.9% 6.5%
Tyres & wheels 4.2% 4.0%
Structure & body 3.3% 1.6%
Fuel & exhaust 1.0% 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 SYM AD05W Jet 4 50 Piaggio Zip
2016 66.3% 71.0%
2017 77.9% 71.7%
2018 67.9% 72.9%
2019 63.9% 73.0%
2020 76.1% 73.1%
2021 75.5% 73.3%
2022 60.5% 74.5%
2023 65.7% 74.1%

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 SYM AD05W Jet 4 50 Piaggio Zip
0k-10k miles 74.3% 75.2%
10k-20k miles 67.1% 66.7%
20k-30k miles 72.6% 64.4%

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

SYM AD05W Jet 4 50 vs Piaggio Zip FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the SYM AD05W Jet 4 50 or the Piaggio Zip?

The Piaggio Zip passes its MOT first time more often than the SYM AD05W Jet 4 50: 71.3% vs 71.2%, a 0.1-point lead. Adjusted for age, mileage and test class the two are level (-0.5 vs -1.0 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 SYM AD05W Jet 4 50 fail its MOT on most?

Lights & signalling: 9.2% of SYM AD05W Jet 4 50 MOT tests failed on it, then steering & suspension (9.0%).

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 SYM AD05W Jet 4 50 or the Piaggio Zip?

At 20k-30k miles the SYM AD05W Jet 4 50 passes first time more often: 72.6% for the SYM AD05W Jet 4 50 vs 64.4% for the Piaggio Zip.

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