BIKERELIABILITY Reg check
League table/ SYM Jet 14 125 E4/vs Piaggio Vespa
Head-to-head · 2005–2025

Data as of: DVSA MOT results to 2025

SYM Jet 14 125 E4 vs Piaggio Vespa

The Piaggio Vespa passes its MOT first time more often than the SYM Jet 14 125 E4: 80.7% vs 73.8%, a 6.9-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025
Metric SYM Jet 14 125 E4 Piaggio Vespa
First-time pass rate 73.8% 80.7%
Outright fail rate 17.4% 12.2%
Vs comparable bikes (age & mileage adjusted) 0.0 pts +5.9 pts
Engine size 125cc 124cc
Rank among all models #4421 of 5428 #3439 of 5428
Median miles at test 9,914 10,023
MOT tests analysed 1,562 287,482
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 Jet 14 125 E4 Piaggio Vespa
Lights & signalling 8.5% 6.4%
Brakes 9.8% 3.5%
Tyres & wheels 5.3% 3.8%
Steering & suspension 3.3% 3.2%
Structure & body 1.6% 1.4%
Fuel & exhaust 0% 1.3%

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 Jet 14 125 E4 Piaggio Vespa
2020 85.2% 85.6%
2021 78.1% 85.8%
2022 72.7% 86.6%
2023 71.4% 86.5%
2024 72.9% 87.2%
2025 73.2% 87.4%

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 SYM Jet 14 125 E4 Piaggio Vespa
0k-10k miles 77.6% 85.0%
10k-20k miles 69.2% 77.0%
20k-30k miles 67.6% 75.3%
30k-40k miles 68.9% 75.4%

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

SYM Jet 14 125 E4 vs Piaggio Vespa FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the SYM Jet 14 125 E4 or the Piaggio Vespa?

The Piaggio Vespa passes its MOT first time more often than the SYM Jet 14 125 E4: 80.7% vs 73.8%, a 6.9-point lead. Adjusted for age, mileage and test class, the Piaggio Vespa still comes out ahead: 0.0 points vs comparable bikes for the SYM Jet 14 125 E4, +5.9 for the Piaggio Vespa. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the SYM Jet 14 125 E4 fail its MOT on most?

Brakes: 9.8% of SYM Jet 14 125 E4 MOT tests failed on it, then lights & signalling (8.5%).

What does the Piaggio Vespa fail its MOT on most?

Lights & signalling: 6.4% of Piaggio Vespa MOT tests failed on it, then tyres & wheels (3.8%).

Which holds up better at high mileage, the SYM Jet 14 125 E4 or the Piaggio Vespa?

At 30k-40k miles the Piaggio Vespa passes first time more often: 68.9% for the SYM Jet 14 125 E4 vs 75.4% for the Piaggio Vespa.

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