Know Your MOT

MOT failure rate and common problems for the Riley 9hp, and how to check your own car by registration.

Updated 05 September 2026.

2.0%fail rate

Riley 9hp MOT failure rate

What a Riley 9hp fails its MOT on, and the part that fixes each.

What it fails on, and why

Lamps & electrical100.0% 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.

Brakes100.0% of failures

Brake failures cover worn pads and discs, an imbalance between wheels, corroded or scored discs, or a binding caliper. Braking efficiency is measured on a rolling road, so a spongy or pulling brake shows up as a low reading.

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: Riley 9hp headlight and indicator bulbsShop Riley 9hp headlight and indicator bulbs on AmazonaffiliateFind Riley 9hp headlight and indicator bulbs on eBayaffiliate
For the brakes failure: Riley 9hp brake pads and discsShop Riley 9hp brake pads and discs on AmazonaffiliateFind Riley 9hp brake pads and discs on eBayaffiliate

Other models

Riley Elf MOT failures22.8% failure rateRiley 1.5 MOT failures16.6% failure rateRiley Kestrel MOT failures14.5% failure rateFord Fiesta MOT failures27.1% failure rate

Questions and answers

What is the MOT failure rate of the Riley 9hp?

It fails 2.0% of its MOT tests across the DVSA record, from 50 tests.

What do these cars fail their MOT on most?

The most common failure area is lamps & electrical, at 100.0% of this model's failures.