Harley Davidson Fat Boy MOT Pass Rate
Overall pass rate across all manufacture years, based on 2,105 real MOT test results. Failure rate: 10.6%.
Data from official DVSA MOT testing records
Harley Davidson Fat Boy MOT Reliability Overview
The Harley Davidson Fat Boy is a niche vehicle in the UK, with 2,105 MOT test results recorded in our database spanning 24 manufacture years. It has an overall MOT pass rate of 89.4% and a failure rate of 10.6%, which is well above the UK average of approximately 37%.
Based on this data, the Harley Davidson Fat Boy earns a "Excellent" reliability rating. The average Harley Davidson Fat Boy presents for MOT with approximately 18,758 miles on the clock. Manufacture year matters: 2004 models achieve the highest pass rate at 96.7%, while 2008 models have the lowest at 72.2%. This 24.5 percentage point difference suggests notable variation in build quality or component durability across production years.
The most common MOT failure for the Harley Davidson Fat Boy is Motorcycle lamps and reflectors, affecting 4.0% of all tests. Lighting failures cover all external lights: headlights, tail lights, brake lights, indicators, fog lights, and reflectors. A single blown bulb will cause an MOT fail. This is one of the most preventable failure categories. The second most common issue is Motorcycle lighting and signalling at 3.8%. Motorcycle brakes rounds out the top three at 3.0%. Together, these top 3 failure categories account for a significant portion of all MOT failures for this model.
Top failures across all manufacture years combined. Individual year pages may show different top failures.
What Fails Most
Best Year to Buy
📈 How Each Vintage Ages
Pass Rate by Manufacture Year
* High Fail Rate badge indicates an MOT pass rate below 65% (failure rate above 35%).
What Fails on This Car?
Click a category to see specific failure items.
View as table
| Rank | Failure Category | Rate (%) | Count |
|---|---|---|---|
| 1 | Motorcycle Lighting And Signalling | 4.6% | 96 |
| 2 | Motorcycle Lamps And Reflectors | 4.0% | 85 |
| 3 | Motorcycle Brakes | 3.0% | 64 |
| 4 | Motorcycle Structure And Attachments | 2.3% | 49 |
| 5 | Motorcycle Reg Plates And Vin | 1.9% | 41 |
| 6 | Motorcycle Fuel And Exhaust | 1.5% | 32 |
| 7 | Identification Of The Vehicle | 1.0% | 21 |
| 8 | Motorcycle Tyres And Wheels | 0.9% | 19 |
| 9 | Motorcycle Tyres | 0.8% | 17 |
| 10 | Motorcycle Steering And Suspension | 0.6% | 13 |
| 11 | Motorcycle Suspension | 0.4% | 9 |
| 12 | Motorcycle Audible Warning (Horn) | 0.3% | 6 |
| 13 | Lamps, Reflectors And Electrical Equipment | 0.2% | 5 |
| 14 | Motorcycle Steering | 0.2% | 4 |
| 15 | Motorcycle Body And Structure | 0.1% | 3 |
Failures per 10,000 Miles
avg. 18,758 miFor every 10,000 miles driven, this shows what percentage of MOT tests fail for each category. This accounts for how far cars are actually driven, not just raw pass/fail counts.
View as table
| Category | Rate / 10K mi | Raw % | Count |
|---|---|---|---|
| Motorcycle lighting and signalling | 2.43 | 4.6% | 96 |
| Motorcycle lamps and reflectors | 2.15 | 4.0% | 85 |
| Motorcycle brakes | 1.62 | 3.0% | 64 |
| Motorcycle structure and attachments | 1.24 | 2.3% | 49 |
| Motorcycle reg plates and vin | 1.04 | 1.9% | 41 |
| Motorcycle fuel and exhaust | 0.81 | 1.5% | 32 |
| Identification of the vehicle | 0.53 | 1.0% | 21 |
| Motorcycle tyres and wheels | 0.48 | 0.9% | 19 |
| Motorcycle tyres | 0.43 | 0.8% | 17 |
| Motorcycle steering and suspension | 0.33 | 0.6% | 13 |
| Motorcycle suspension | 0.23 | 0.4% | 9 |
| Motorcycle audible warning (Horn) | 0.15 | 0.3% | 6 |
| Lamps & Electrical | 0.13 | 0.2% | 5 |
| Motorcycle steering | 0.10 | 0.2% | 4 |
| Motorcycle body and structure | 0.08 | 0.1% | 3 |
🚗 Similar Cars to Consider
Mileage at MOT
The average Harley Davidson Fat Boy has 18,758 miles when tested for MOT.
📊 Mileage-Adjusted Failure Rate
How often this car fails MOT relative to how much it's driven — a fairer comparison than raw pass rate.
The Harley Davidson Fat Boy has a mileage-adjusted failure rate of 5.65% per 10,000 miles driven. The average across all makes is 5.38%, so this model is worse than average.
About Harley Davidson Fat Boy MOT Data
The Harley Davidson Fat Boy is a niche vehicle in the UK, with 2,105 MOT test results recorded in our database spanning 24 manufacture years. It has an overall MOT pass rate of 89.4% and a failure rate of 10.6%, which is well above the UK average of approximately 37%.
For Harley Davidson Fat Boy owners, these results suggest a reliable vehicle that generally passes its MOT without major issues. Focus your pre-MOT checks on motorcycle lamps and reflectors and motorcycle lighting and signalling for the best chance of a first-time pass. Use our detailed year-by-year breakdown and failure analysis below to understand how your specific Fat Boy is likely to perform.
Motorcycle lamps and reflectors — 4.0% of failures
Motorcycle lamps and reflectors issues account for 4.0% of MOT failures on the Harley Davidson Fat Boy. Lighting failures cover all external lights: headlights, tail lights, brake lights, indicators, fog lights, and reflectors. A single blown bulb will cause an MOT fail. This is one of the most preventable failure categories. Typical repair costs: £5–50. Pre-MOT check: Walk around the car and check every light — headlights (dipped and main beam), side lights, tail lights, brake lights, indicators, hazard lights, reverse light, rear fog light, and number plate lights. Replace any blown bulbs before the test.
Motorcycle lighting and signalling — 3.8% of failures
Motorcycle lighting and signalling issues account for 3.8% of MOT failures on the Harley Davidson Fat Boy. Motorcycle lighting and signalling issues are a common cause of MOT failure. Regular inspection and maintenance of these components helps ensure your vehicle passes its MOT. Typical repair costs: £100–400. Pre-MOT check: Have this system checked during regular servicing. Look for warning signs like unusual noises, vibrations, or dashboard warning lights.
Motorcycle brakes — 3.0% of failures
Motorcycle brakes issues account for 3.0% of MOT failures on the Harley Davidson Fat Boy. Brake-related failures include worn brake pads, corroded brake discs, leaking brake lines, and faulty brake servos. These are safety-critical components — any brake deficiency will result in an MOT fail. Typical repair costs: £150–400. Pre-MOT check: Listen for squealing or grinding noises. Check brake pedal feel — if it feels spongy or goes to the floor, have the system inspected immediately. Look at brake pad thickness through the wheel spokes (minimum 3mm).
Frequently Asked Questions
What is the MOT pass rate for the Harley Davidson Fat Boy?
Based on 2,105 MOT tests in our database, the Harley Davidson Fat Boy has an overall pass rate of 89.4% (10.6% fail rate).
What are the most common MOT failures on a Harley Davidson Fat Boy?
The top 3 reasons a Harley Davidson Fat Boy fails its MOT are: 1. Motorcycle lamps and reflectors (4.0%), 2. Motorcycle lighting and signalling (3.8%), 3. Motorcycle brakes (3.0%). Check these areas before booking your MOT.
Is the Harley Davidson Fat Boy reliable?
With a 10.6% MOT failure rate, the Fat Boy is more reliable than average compared to the UK average of ~40%.
What should I check before an MOT on my Harley Davidson Fat Boy?
Based on failure data, focus on: Motorcycle lamps and reflectors (4.0%); Motorcycle lighting and signalling (3.8%); Motorcycle brakes (3.0%). These are the areas most likely to cause a fail. Also check all lights, tyres (minimum 1.6mm tread), and windscreen condition — these are quick wins that apply to all cars.
Based on DVSA anonymised MOT test data (2005–2024). Crown copyright, Open Government Licence v3.0.