Yamaha XT660X MOT pass rate and common failures
Yamaha XT660X motorcycles pass the MOT 84.98% of the time, measured across 253 tests in the DVSA record. A further 7.51% passed only after a defect was put right at the test station.
What to check before the MOT
Built from this model's own failure record, not general advice.
- Start with not working - it accounts for 52.6% of failed tests on this model.
- Then check missing and tread depth is below minimum requirements of 1.0mm, the next two most common reasons.
- The most common advisory is noise is clearly in excess of that emitted by a similar motorcycle fitted with a standard silencer in average condition (15.4% of all tests) - not a failure, but money you will spend sooner or later.
- Average recorded mileage at test is 21,429 miles, which is the number to compare any advert against.
Pass rate by age
A single pass rate hides the most useful thing in this data: how the same model behaves at three years old and at fifteen.
| Age at test | Pass rate | Tests | |
|---|---|---|---|
| 11-15 years | 83.05% | 59 | |
| 16+ years | 85.49% | 193 |
Why the Yamaha XT660X fails
Share of failed tests on this model where the item was recorded. One test can fail on several items, so the column does not add up to 100%.
| # | Item | Of failures | Tests | |
|---|---|---|---|---|
| 1 | Not working | 52.6% | 10 | |
| 2 | Missing | 21.1% | 4 | |
| 3 | Tread depth is below minimum requirements of 1.0mm | 21.1% | 4 | |
| 4 | Has excessive play | 15.8% | 3 | |
| 5 | Too low | 15.8% | 3 | |
| 6 | Contaminated | 10.5% | 2 | |
| 7 | Does not illuminate by the operation of both brake controls | 10.5% | 2 | |
| 8 | Inoperative in the case of multiple lamps or light sources | 10.5% | 2 | |
| 9 | Insecure | 10.5% | 2 | |
| 10 | Not working on dipped beam | 10.5% | 2 |
Most common advisories
Not a failure and not a legal requirement to fix - but an advisory that repeats year after year is money the next owner spends.
| # | Item | Of all tests | Tests | |
|---|---|---|---|---|
| 1 | Noise is clearly in excess of that emitted by a similar motorcycle fitted with a standard silencer in average condition | 15.4% | 39 | |
| 2 | Tread depth is below minimum requirements of 1.0mm | 6.3% | 16 | |
| 3 | Has a serious fluid leak | 3.6% | 9 | |
| 4 | Significantly and obviously worn | 3.6% | 9 | |
| 5 | Has excessive play | 2.8% | 7 | |
| 6 | Less than 1.0 mm thick | 2.8% | 7 | |
| 7 | Excessively loose | 2.4% | 6 | |
| 8 | Indicates excessive fluctuation of brake effort | 2.4% | 6 | |
| 9 | Worn to excess | 2.4% | 6 | |
| 10 | Chain guard missing | 1.6% | 4 |
Yamaha XT660X for sale
No Yamaha XT660X in stock at the moment - 82 other Yamaha bikes are advertised.
Similar bikes compared
Models of comparable capacity, so the comparison means something.
| Model | Tests | Pass rate | Avg mileage | |
|---|---|---|---|---|
| Honda CB 397-750cc · 397-750cc | 5,400 | 89.76% | 19,444 | |
| Honda NC · 741cc | 5,311 | 89.53% | 22,765 | |
| Suzuki GSF600 · 600cc | 4,890 | 80% | 29,308 | |
| Honda CBR600F · 599cc | 4,710 | 85.56% | 30,651 | |
| Kawasaki ZX-6R · 599-636cc | 4,510 | 81.62% | 26,019 | |
| Suzuki SV650 · 646cc | 3,834 | 80.99% | 27,644 |
Source: DVSA MOT testing data, 2025 · updated Aug 2026 · licence and method