Gilera GP 800 vs Yamaha FZS600

The Gilera GP 800 and Yamaha FZS600 have an identical 82.6% first-time MOT pass rate.

MOT reliability, side by side

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

Metric	Gilera GP 800	Yamaha FZS600
First-time pass rate	82.6%	82.6%
Outright fail rate	12.2%	10.6%
Vs comparable bikes (age & mileage adjusted)	-2.0 pts	-0.8 pts
Engine size	839cc	599cc
Rank among all models	#3052 of 5428	#3052 of 5428
Median miles at test	18,404	21,612
MOT tests analysed	690	136,558
Most common failure	brakes	brakes

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	Gilera GP 800	Yamaha FZS600
Brakes	4.8%	4.5%
Lights & signalling	5.2%	3.4%
Steering & suspension	4.1%	2.7%
Tyres & wheels	3.2%	2.9%
Structure & body	1.0%	1.1%
Drive system	1.0%	0.9%
Fuel & exhaust	0.1%	1.1%

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	Gilera GP 800	Yamaha FZS600
2015	82.7%	81.1%
2016	89.6%	82.2%
2017	77.6%	82.0%
2018	86.1%	81.3%
2019	71.0%	83.0%
2021	91.4%	82.8%
2022	70.6%	83.6%
2023	84.4%	84.2%

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	Gilera GP 800	Yamaha FZS600
0k-10k miles	88.4%	89.6%
10k-20k miles	82.6%	85.5%
20k-30k miles	82.0%	81.4%
30k-40k miles	75.3%	78.7%
40k-50k miles	81.4%	76.8%

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

Gilera GP 800 vs Yamaha FZS600 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the Gilera GP 800 or the Yamaha FZS600?

The Gilera GP 800 and Yamaha FZS600 have an identical 82.6% first-time MOT pass rate. Adjusted for age, mileage and test class, the Yamaha FZS600 still comes out ahead: -2.0 points vs comparable bikes for the Gilera GP 800, -0.8 for the Yamaha FZS600. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the Gilera GP 800 fail its MOT on most?

Lights & signalling: 5.2% of Gilera GP 800 MOT tests failed on it, then brakes (4.8%).

What does the Yamaha FZS600 fail its MOT on most?

Brakes: 4.5% of Yamaha FZS600 MOT tests failed on it, then lights & signalling (3.4%).

Which holds up better at high mileage, the Gilera GP 800 or the Yamaha FZS600?

At 40k-50k miles the Gilera GP 800 passes first time more often: 81.4% for the Gilera GP 800 vs 76.8% for the Yamaha FZS600.

GILERA GP 800 82.6% pass · 690 tests YAMAHA FZS600 82.6% pass · 137k tests

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