MOT failure rate and common problems for the Bsa B50mx, and how to check your own car by registration.

Updated 05 September 2026.

13.7%fail rate

Bsa B50mx MOT failure rate

What a Bsa B50mx fails its MOT on, and the part that fixes each.

What it fails on, and why

Lamps & electrical28.6% of failures

Lighting is the single most common MOT failure and the cheapest to put right. A blown headlight, brake-light or number-plate bulb, a cracked lens, or a headlamp beam that points too high or low will all fail. Most are a two-minute bulb swap.

Tyres14.3% of failures

Tyres fail for tread below the 1.6mm legal limit across the central three-quarters, uneven or exposed-cord wear, or sidewall damage. The tester inspects all four; a single illegal tyre is a fail.

The parts that fix each

If your car has just failed, you have 10 working days to fix the items and get a free partial retest. Confirm the exact fitment against your registration or VIN before buying.

For the lamps & electrical failure: Bsa B50mx headlight and indicator bulbsShop Bsa B50mx headlight and indicator bulbs on Amazonaffiliate Find Bsa B50mx headlight and indicator bulbs on eBayaffiliate

For the tyres failure: Bsa B50mx tyresShop Bsa B50mx tyres on Amazonaffiliate Find Bsa B50mx tyres on eBayaffiliate

Other models

All Bsa models MOT failure rates comparedRanked worst to best Bsa A10 MOT failures7.9% failure rate Bsa Bantam MOT failures10.3% failure rate Ford Fiesta MOT failures27.1% failure rate

Questions and answers

What is the MOT failure rate of the Bsa B50mx?

It fails 13.7% of its MOT tests across the DVSA record, from 51 tests.

What do these cars fail their MOT on most?

The most common failure area is lamps & electrical, at 28.6% of this model's failures.