BIKERELIABILITY
MOT DATA · GREAT BRITAIN · 2005–2025
League table/ HARLEY-DAVIDSON/FLSTF FATBOY 1584 11
Model report · 2005–2025

HARLEY-DAVIDSON FLSTF FATBOY 1584 11

1585cc Petrol Class 2
88.6%
first-time pass rate
4.6%
failed outright
7,978
median miles at test
569
MOT tests, 2005–2025

Pass rate over time

first-time pass rate by test year · 2014–2025

The FLSTF FATBOY 1584 11's first-time pass rate has risen 4.6 points since 2014, 81.1% to 85.7%.

78%88%99%2014: 81.1% pass (53 tests)2015: 87.9% pass (58 tests)2016: 89.8% pass (59 tests)2017: 91.2% pass (57 tests)2018: 87.2% pass (47 tests)2019: 94.9% pass (39 tests)2020: 89.7% pass (39 tests)2021: 95.3% pass (43 tests)2022: 84.1% pass (44 tests)2023: 85.7% pass (49 tests)2024: 91.9% pass (37 tests)2025: 85.7% pass (35 tests)20142025

Pass rate by mileage

how the FLSTF FATBOY 1584 11's first-time pass rate falls with the odometer · class average 84.9%

A low-mileage FLSTF FATBOY 1584 11 passes first time 89.5% of the time; by 20k that's 92.0%.

84%89%93%0k: 89.5% pass (354 tests)10k: 85.7% pass (147 tests)20k: 92.0% pass (50 tests)0k10k20k

First-time pass rate by odometer reading at test, 10,000-mile bands for this model. Mileage is the strongest reliability signal. See the full curve.

What fails on a FLSTF FATBOY 1584 11

failure defects by component group · advisories excluded
Component group Share of defects Defects % of defects vs all bikes
tyres
9 27.3 2.3×
brakes
7 21.2 0.3×
lamps and reflectors
5 15.2 0.4×
tyres and wheels
4 12.1 0.3×
steering
2 6.1 0.8×
lighting and signalling
2 6.1 0.1×
Identification of the vehicle
1 3 0.8×
steering and suspension
1 3 0.1×
structure and attachments
1 3 0.3×
suspension
1 3 0.2×

Defects recorded against failed normal tests, 2005–2025, grouped by DVSA inspection section. One test can record multiple defects. "vs all bikes" is how often this model's tests record a defect in the group, as a multiple of the all-bike rate.

How rivals compare

same type, similar capacity, high test volume

On first-time pass rate the FLSTF FATBOY 1584 11 beats 1 of its 4 closest rivals (HARLEY-DAVIDSON FLSTF, HARLEY-DAVIDSON FLSTC, HARLEY-DAVIDSON XL1200C).

Rivals share this bike's type and sit within ±30% of its engine capacity, ≥ 5,000 tests. Card colour = better/worse first-time pass rate than the FLSTF FATBOY 1584 11.

Pass rate by registration year

how each model-year cohort fares · registration year from first use date

Best year to buy used: 2011 (88.8% pass). Weakest: 2010 (87.4%).

87%88%90%2010: 87.4% pass (87 tests)2011: 88.8% pass (454 tests)20102011

First-time pass rate by the year each bike was first registered (cohorts with ≥ 50 tests). Older cohorts are survivors: the worst examples have already left the road, which tends to lift the earliest years.

HARLEY-DAVIDSON FLSTF FATBOY 1584 11 FAQ

answers computed from the data above · terms in the glossary

Is the HARLEY-DAVIDSON FLSTF FATBOY 1584 11 reliable?

The HARLEY-DAVIDSON FLSTF FATBOY 1584 11 is more reliable than average for its class: 88.6% of its 569 MOT tests (2005–2025) passed first time, against a class average of 84.9%. That ranks it #1400 of 5426 models.

What does a FLSTF FATBOY 1584 11 fail its MOT on most?

tyres — 27% of all defects recorded against failed FLSTF FATBOY 1584 11 tests.

How many miles will a FLSTF FATBOY 1584 11 last?

The median FLSTF FATBOY 1584 11 shows 7,978 miles at test, and examples around 20k miles still pass 92.0% of the time — mileage alone rarely kills one.