The picture
R850: a strong MOT record by UK norms
Across 647 MOT tests, the R850 returns 86.2% first-time pass — comfortably ahead of the UK fleet average. The single most-logged Major fail is a binding brake. A non-functioning shock absorber and a stop-lamp out round out the top three. Average tested mileage sits at 39,516, which is the lens to read those failure rankings through. If you own one and the next test is close, the ranked list below is a sensible pre-test checklist.
Top ten reasons for rejection.
- 01
Significant brake effort recorded with no brake applied indicating a binding brake
9 occurrences · 1.4% of tests
- 02
A shock absorber not functioning or leaking severely
7 occurrences · 1.1% of tests
- 03
Stop lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning
6 occurrences · 0.9% of tests
- 04
Excessive fluctuation in brake effort through each wheel revolution
5 occurrences · 0.8% of tests
- 05
A lamp missing or inoperative
4 occurrences · 0.6% of tests
- 06
A stop lamp(s) remains on when the brakes are released
4 occurrences · 0.6% of tests
- 07
A suspension pin, bush or joint excessively worn
4 occurrences · 0.6% of tests
- 08
Brake lining or pad worn below 1.0mm
3 occurrences · 0.5% of tests
- 09
Reflector missing or reflecting white to the rear
3 occurrences · 0.5% of tests
- 10
Tyre tread depth not in accordance with the requirements
3 occurrences · 0.5% of tests
Counts cover Major and Dangerous defects logged at test. Advisory items excluded so this shows why a car was rejected, not just what the tester flagged in passing.
Try the calculator
Build your own retest budget.
Tools that pre-empt a retest.
Picked against this car's top failure patterns. Affiliate links to Amazon UK — we earn a small cut at no cost to you. Disclosed up-front, doesn't shape the data.
Buying or keeping a R850?
Use the failure ranking as a pre-test checklist or a haggling lever. Treat the headline pass rate as a fleet-wide trend, not a guarantee on any individual car.
If you own a R850 and your last MOT looked nothing like the ranked failures above, that's normal — individual cars vary widely. The ranking shows the patterns testers flag most often across the country.