2020 Kawasaki BX 125 Alfa 0.1L Petrol · AK70 PLU

A defining mechanical concern has emerged in the most recent testing for this 2020 Kawasaki BX 125, where the 27 November 2025 MOT produced both a pass and a fail on the same day. The failure was driven by dangerous rear brake pad wear with less than 1.0 mm of friction material remaining, accompanied by a major defect for an excessively loose drive chain and a persistent advisory noting rear brake effort fluctuation. The earlier record from 2022 through 2024 was entirely clean across three consecutive passes, so the sudden emergence of brake wear, chain stretch, and an advisory for a noisy exhaust in late 2025 represents a notable shift from a previously unblemished roadworthiness history. While the brake pads appear to have been addressed prior to the same-day pass, the presence of an unbalanced rear brake and a worn chain suggests a machine whose serviceable components have not been kept current with the demands of regular riding. Recorded mileage stands at 13,565 miles over roughly six years, equating to around 2,260 miles annually, which is modest for a small-capacity motorcycle and typical of light commuter or errand-running use. Three MOT entries are recorded at almost exactly annual intervals from 2022 to 2025, with no multi-year lay-up gaps that might raise concerns about stale fuel, degraded rubber, or dormant brake hydraulics. Low annual mileage of this nature does, however, mean that consumable wear tends to be governed more by calendar age and exposure than by distance, with brake pads, chains, sprockets, and tyres all susceptible to hardening, corrosion, and surface degradation even when the odometer advances slowly. A prospective buyer should focus directly on the braking and drivetrain components flagged in the recent test. On a test ride, the rear brake should be assessed for a firm, progressive lever or pedal feel with the bike stationary, and any pulsation, grabbing, or uneven retardation when slowing from speed would corroborate the recorded fluctuation in brake effort and could point to a binding or partially seized caliper, warped brake disc, or contaminated pads. The chain should be inspected along its entire run for slack at the midpoint of the lower run, with the rear wheel pushed forward to check for tight spots that indicate uneven stretching, and the sprocket teeth examined for the characteristic hooked or shark-fin profile that typically accompanies a chain that has run loose for any length of time. A slow-speed pass over uneven surfaces and through gentle direction changes will also reveal any chain or sprocket noise that might otherwise be masked at higher road speeds. Given the abrupt contrast between the clean 2022 to 2024 record and the cluster of brake and drivetrain defects in November 2025, it would be prudent to verify the date and mileage stamp of the replacement rear brake pads and any chain or sprocket work, as well as to confirm whether the noisy exhaust advisory reflects a deteriorated mounting or a more substantive system concern. The lack of any recorded suspension, lighting, or structural advisories across all four tests is a positive indicator that the chassis, wheel bearings, and electrical systems have remained within tolerance, suggesting the November 2025 issues are localised rather than symptomatic of broader deterioration. Overall, the record indicates a motorcycle that has been kept on the road and tested consistently, but the late 2025 failure warrants a careful physical inspection of the braking system and final drive before purchase.