JM Star JSD 50 QT-13 vs Piaggio Zip

The Piaggio Zip passes its MOT first time more often than the JM Star JSD 50 QT-13: 71.3% vs 61.4%, a 9.9-point lead.

MOT reliability, side by side

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

Metric	JM Star JSD 50 QT-13	Piaggio Zip
First-time pass rate	61.4%	71.3%
Outright fail rate	28.8%	20.4%
Vs comparable bikes (age & mileage adjusted)	-16.2 pts	-1.0 pts
Engine size	50cc	49cc
Rank among all models	#5168 of 5428	#4631 of 5428
Median miles at test	2,832	8,882
MOT tests analysed	285	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.

Pass rate by test year

first-time MOT pass rate in each calendar year both bikes were tested

Test year	JM Star JSD 50 QT-13	Piaggio Zip
2010	59.5%	70.8%
2011	56.3%	69.7%
2012	54.2%	69.1%
2013	55.6%	69.7%
2014	71.4%	68.8%

Each year mixes bikes of different ages, so a fleet that is getting older tends to slip.

JM STAR JSD 50 QT-13 61.4% pass · 285 tests PIAGGIO ZIP 71.3% pass · 79.0k tests

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