HarleyMotorcyclePartsHarley how-to guides
Job-by-job guides written for Harley-Davidson motorcycles specifically — the three separate fluids, the belt final drive, the things that are genuinely different about these bikes. Procedure and judgement, with the model-specific numbers left where they belong: your service manual.
Jobs for any Harley
Drive Belt Inspection, Tension and Replacement
Your Harley has a belt, not a chain — how to inspect it, what kills it, and when it has to come off.
Primary Chaincase Fluid Change
Harley runs three separate fluids — and the primary is the one owners forget. How to change it properly.
Transmission Fluid Change
The third fluid on a Big Twin, and the one most likely never to have been changed.
Seat Removal and Replacement
One of the easiest jobs on the bike, and the gateway to half the others.
Brake Light Switch Diagnosis and Replacement
Bulb fine but no brake light? It is usually the switch — and there are two of them.
Air Filter Service and Replacement
The cheapest job on the bike and the one with the most visible effect on how it runs.
Spark Plug Replacement and Reading
Changing them is easy. Reading them tells you what the engine has been doing.
Clutch Cable Adjustment
Dragging clutch, hard to find neutral, or slipping under load — usually free play, not a worn clutch.
Brake Pad Inspection and Replacement
How to tell when pads are done, and how to change them without ruining a caliper or a disc.
Fork Oil Change
Forks that dive, clunk or weep have usually just never had the oil changed.
Tyre Pressure, Wear and When to Replace
The sidewall number is not your pressure — and the date code matters as much as the tread.
Wheel Bearing Inspection
A five-minute check that catches a failure you really do not want at speed.
Steering Head Bearing Check and Adjustment
That notch at dead-ahead, or the weave at speed, is usually here.
Charging System Diagnosis
Flat battery again? Test the charging system before you buy a single part.
Exhaust Leaks and Gasket Replacement
That tick at idle that goes away as it warms up is a leak, and it will not fix itself.
Handlebar Replacement — and the Three Things It Drags With It
Changing bars is easy. Changing bars without also buying cables is where it goes wrong.
Winter Storage and Bringing It Back
Most storage damage is done by doing nothing — and by one well-meant habit that makes it worse.
Finding an Oil Leak
Work out where it is coming FROM before you buy a single gasket.
Throttle Cables: Free Play, Routing and Replacement
There are two of them, and that is why yours still sticks after you replaced "the cable".
Rear Suspension Preload and Setting Sag
Preload does not make the suspension stiffer. Knowing what it actually does fixes most complaints.
The Pre-Ride Inspection That Takes Five Minutes
Most riders check tyre pressure and nothing else. Here is the rest of it, in order.
Chrome, Paint and Leather Care
The bottle under your kitchen sink is what is pitting your chrome.
Fuel Filter and Fuel System Service
On most EFI Harleys the filter is inside the tank — this is not a ten-minute inline swap.
Engine Noises: What Is Normal and What Is Not
Some Harley noises are just how the engine sounds. Knowing which is which saves a fortune.
Forward and Mid Controls: Fitting and the Part People Forget
Moving the pedals moves your brake geometry with them, and that needs resetting.
Your First Harley Toolkit — and Why Your Metric Set Will Not Do
A Harley is SAE and Torx. That is the most expensive wrong assumption a new owner makes.
Rear Drive Chain on a Harley: Which Bikes Have One, Adjustment and Replacement
Most Harleys run a belt. Here is how to tell, and how to adjust, clean and replace a rear chain on the ones that do not.
Twin Cam Cam Chain Tensioners: Inspection and the Shoe Wear Problem
The chain inside the Twin Cam engine that nobody talks about until its tensioner shoe is in pieces.
Rear shock replacement by model
Fifty bikes, each written for how that bike is built and ridden.
Touring
Trikes
Softail
Dyna
Sportster
Fuel line replacement by model
Fifteen of the most common bikes. Read the safety steps before touching a pressure line.
Primary chain inspection, adjustment and replacement by model
The chain a Harley owner actually changes: engine to clutch, inside the primary case. Twenty-four of the most popular bikes. Rear chain? See the final drive chain guide above.
Touring
Trikes
Softail
Dyna
Sportster
Looking for your specific model? The maintenance guides cover oil changes, bulbs, batteries and cold starts bike by bike.