The picture
St1100: a strong MOT record by UK norms
Across 2,041 MOT tests, the St1100 returns 85.3% 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 tyre tread under the limit round out the top three. Average tested mileage sits at 54,282, 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
38 occurrences · 1.9% of tests
- 02
A shock absorber not functioning or leaking severely
38 occurrences · 1.9% of tests
- 03
Tyre tread depth not in accordance with the requirements
35 occurrences · 1.7% of tests
- 04
Brake lining or pad worn below 1.0mm
18 occurrences · 0.9% of tests
- 05
A suspension component excessively damaged or corroded
15 occurrences · 0.7% of tests
- 06
Handlebar grip insecure to handlebar
13 occurrences · 0.6% of tests
- 07
Excessive fluctuation in brake effort through each wheel revolution
12 occurrences · 0.6% of tests
- 08
A tyre valve seriously damaged or misaligned likely which could cause sudden deflation of the tyre
12 occurrences · 0.6% of tests
- 09
Stop lamp missing, inoperative or in the case of a multiple light source more than 1/2 not functioning
11 occurrences · 0.5% of tests
- 10
Significant brake effort recorded with no brake applied indicating a binding brake
11 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.
Worst-case fix budget · top 2 failures
£140–£255
If every one of this St1100'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
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
Item 02 · 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
Buying or keeping a St1100?
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 St1100 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.