Vespa (douglas) Cosa vs Lambretta LI150

The Lambretta LI150 passes its MOT first time more often than the Vespa (douglas) Cosa: 88.8% vs 80.0%, a 8.8-point lead.

MOT reliability, side by side

first-time pass rate, outright fail rate and tests analysed · 2005–2025

Metric	Vespa (douglas) Cosa	Lambretta LI150
First-time pass rate	80.0%	88.8%
Outright fail rate	12.9%	5.9%
Vs comparable bikes (age & mileage adjusted)	+1.8 pts	+6.4 pts
Engine size	198cc	150cc
Median miles at test	11,910	2,944
MOT tests analysed	140	19,294
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.

Pass rate by mileage

first-time MOT pass rate by miles on the clock at test

Mileage	Vespa (douglas) Cosa	Lambretta LI150
0k-10k miles	86.0%	88.8%
10k-20k miles	72.9%	89.8%

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

VESPA (DOUGLAS) COSA 80.0% pass · 140 tests LAMBRETTA LI150 88.8% pass · 19.3k tests

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