The picture
Cb 650 Ra-K: a strong MOT record by UK norms
Across 1,168 MOT tests, the Cb 650 Ra-K returns 88.4% first-time pass — comfortably ahead of the UK fleet average. The single most-logged Major fail is wheel bearing with excessive play. Brake pads worn below 1.0 mm and tyre tread under the limit round out the top three. Average tested mileage sits at 8,524, 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
A wheel bearing with excessive play
18 occurrences · 1.5% of tests
- 02
Brake lining or pad worn below 1.0mm
12 occurrences · 1.0% of tests
- 03
Tyre tread depth not in accordance with the requirements
11 occurrences · 0.9% of tests
- 04
A footrest missing or insecure
10 occurrences · 0.9% of tests
- 05
Significant brake effort recorded with no brake applied indicating a binding brake
9 occurrences · 0.8% of tests
- 06
Reflector missing or reflecting white to the rear
9 occurrences · 0.8% of tests
- 07
Excessive fluctuation in brake effort through each wheel revolution
7 occurrences · 0.6% of tests
- 08
Number plate does not conform to the specified requirements
5 occurrences · 0.4% of tests
- 09
A wheel bearing play so excessive it is likely to break up or directional control impaired
5 occurrences · 0.4% of tests
- 10
Significant brake effort recorded with no brake applied indicating a binding brake
5 occurrences · 0.4% 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.
Worst-case fix budget · top 2 failures
£140–£255
If every one of this CB 650 RA K's most-logged Major fails hit at the same MOT, that's the real-world UK garage range. Reality is usually one or two items, not all of them. Open the estimator →
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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.
Item 01 · Amazon UK
Brake pad measurement gauge
Testers fail pads under 1.5mm. A wear gauge tells you if you've got two months left or two weeks.
Search Amazon UK
Item 02 · Amazon UK
Digital tyre-tread depth gauge
Five quid for a gauge beats £150 for a retest. UK MOT minimum is 1.6mm — most testers fail anything below 2mm to be safe.
Search Amazon UK
Buying or keeping a CB 650 RA K?
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 CB 650 RA K 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.