BIKERELIABILITY
MOT DATA · GREAT BRITAIN · 2005–2025
League table/ HARLEY-DAVIDSON/FXDF FAT BOB 1584 09
Model report · 2005–2025

HARLEY-DAVIDSON FXDF FAT BOB 1584 09

1584cc Petrol Class 2
87.6%
first-time pass rate
4.5%
failed outright
10,610
median miles at test
774
MOT tests, 2005–2025

Pass rate over time

first-time pass rate by test year · 2012–2025

The FXDF FAT BOB 1584 09's first-time pass rate has risen 8.9 points since 2012, 79.7% to 88.6%.

76%87%98%2012: 79.7% pass (69 tests)2013: 87.9% pass (66 tests)2014: 90.6% pass (53 tests)2015: 84.5% pass (58 tests)2016: 83.1% pass (65 tests)2017: 82.8% pass (58 tests)2018: 89.4% pass (47 tests)2019: 91.5% pass (47 tests)2020: 90.7% pass (43 tests)2021: 87.3% pass (55 tests)2022: 90.6% pass (53 tests)2023: 94.2% pass (52 tests)2024: 93.0% pass (43 tests)2025: 88.6% pass (44 tests)20122025

Pass rate by mileage

how the FXDF FAT BOB 1584 09's first-time pass rate falls with the odometer · class average 84.9%

A low-mileage FXDF FAT BOB 1584 09 passes first time 88.8% of the time; by 30k that's 84.0%.

83%87%90%0k: 88.8% pass (357 tests)10k: 86.1% pass (238 tests)20k: 89.2% pass (111 tests)30k: 84.0% pass (50 tests)0k20k30k

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 FXDF FAT BOB 1584 09

failure defects by component group · advisories excluded
Component group Share of defects Defects % of defects vs all bikes
lamps and reflectors
14 25.5 0.7×
tyres and wheels
8 14.5 0.5×
brakes
8 14.5 0.2×
reg plates and vin
7 12.7 1.1×
lighting and signalling
7 12.7 0.2×
suspension
5 9.1 0.9×
steering and suspension
2 3.6 0.1×
tyres
2 3.6 0.4×
Identification of the vehicle
1 1.8 0.6×
steering
1 1.8 0.3×

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 FXDF FAT BOB 1584 09 beats 0 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 FXDF FAT BOB 1584 09.

Pass rate by registration year

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

Best year to buy used: 2008 (89.1% pass). Weakest: 2009 (86.7%).

86%88%90%2008: 89.1% pass (302 tests)2009: 86.7% pass (472 tests)20082009

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 FXDF FAT BOB 1584 09 FAQ

answers computed from the data above · terms in the glossary

Is the HARLEY-DAVIDSON FXDF FAT BOB 1584 09 reliable?

The HARLEY-DAVIDSON FXDF FAT BOB 1584 09 is more reliable than average for its class: 87.6% of its 774 MOT tests (2005–2025) passed first time, against a class average of 84.9%. That ranks it #1722 of 5426 models.

What does a FXDF FAT BOB 1584 09 fail its MOT on most?

lamps and reflectors — 25% of all defects recorded against failed FXDF FAT BOB 1584 09 tests.

How many miles will a FXDF FAT BOB 1584 09 last?

The median FXDF FAT BOB 1584 09 shows 10,610 miles at test, and examples around 30k miles still pass 84.0% of the time — mileage alone rarely kills one.