KTM 640 LC4-E vs Yamaha FZS600

The Yamaha FZS600 passes its MOT first time more often than the KTM 640 LC4-E: 82.6% vs 80.6%, a 2.0-point lead.

MOT reliability, side by side

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

Metric	KTM 640 LC4-E	Yamaha FZS600
First-time pass rate	80.6%	82.6%
Outright fail rate	10.0%	10.6%
Vs comparable bikes (age & mileage adjusted)	-6.8 pts	-0.8 pts
Engine size	625cc	599cc
Rank among all models	#3459 of 5428	#3052 of 5428
Median miles at test	7,836	21,612
MOT tests analysed	8,115	136,558
Most common failure	lighting and signalling	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	KTM 640 LC4-E	Yamaha FZS600
Lights & signalling	6.0%	3.4%
Brakes	1.5%	4.5%
Tyres & wheels	2.4%	2.9%
Steering & suspension	2.4%	2.7%
Drive system	1.0%	0.9%
Structure & body	0.6%	1.1%
Fuel & exhaust	0.5%	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	KTM 640 LC4-E	Yamaha FZS600
2018	83.5%	81.3%
2019	82.2%	83.0%
2020	83.6%	83.6%
2021	79.5%	82.8%
2022	79.6%	83.6%
2023	83.8%	84.2%
2024	88.6%	83.3%
2025	82.5%	84.0%

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	KTM 640 LC4-E	Yamaha FZS600
0k-10k miles	81.9%	89.6%
10k-20k miles	78.9%	85.5%
20k-30k miles	73.2%	81.4%
30k-40k miles	85.4%	78.7%

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

KTM 640 LC4-E vs Yamaha FZS600 FAQ

answers computed from the data above · terms in the glossary

Which is more reliable, the KTM 640 LC4-E or the Yamaha FZS600?

The Yamaha FZS600 passes its MOT first time more often than the KTM 640 LC4-E: 82.6% vs 80.6%, a 2.0-point lead. Adjusted for age, mileage and test class, the Yamaha FZS600 still comes out ahead: -6.8 points vs comparable bikes for the KTM 640 LC4-E, -0.8 for the Yamaha FZS600. An MOT checks roadworthiness items, not engine or gearbox internals.

What does the KTM 640 LC4-E fail its MOT on most?

Lights & signalling: 6.0% of KTM 640 LC4-E MOT tests failed on it, then tyres & wheels (2.4%).

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 KTM 640 LC4-E or the Yamaha FZS600?

At 30k-40k miles the KTM 640 LC4-E passes first time more often: 85.4% for the KTM 640 LC4-E vs 78.7% for the Yamaha FZS600.

KTM 640 LC4-E 80.6% pass · 8,115 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.