Why a 2000 Road King fuel injection line upgrade matters
The 2000 Harley-Davidson Road King came with rubber fuel lines that degrade over time, especially if the bike sits unused or is exposed to heat and UV light. Original lines can crack, leak, or fail internally — restricting fuel flow to the injectors and causing hard starts, rough idle, or stalling. Upgrading to braided stainless steel or reinforced fuel lines prevents leaks, handles fuel system pressure more reliably, and gives you clearer visibility of fuel condition if you choose transparent sections.
This is not a mandatory recall or safety defect, but a maintenance upgrade that many Road King owners do between 15,000 and 30,000 miles, or whenever they notice fuel smell, performance dips, or visible line cracking. The job itself is straightforward enough for a home mechanic with basic tools, though it does require draining the fuel tank or working carefully around a full one.
Key Takeaways
- Original rubber fuel lines on a 2000 Road King degrade from heat and age, and replacement with braided stainless steel lines prevents leaks and improves reliability.
- You will need to remove the fuel tank to access both the fuel pump inlet line and the injector supply line, which means draining or siphoning the tank first.
- Braided stainless lines, fittings, and clamps cost between $80 and $200 depending on whether you buy a kit or source parts separately.
- The job takes two to four hours for a home mechanic and requires only basic hand tools, a fuel line removal tool, and care around the fuel pump connector.
- OEM Harley lines and aftermarket braided kits are both available; braided lines are more durable but OEM replacements are a direct swap if you prefer stock appearance.
What fuel lines you need and where to source them
A 2000 Road King has two main fuel lines: the inlet line from the tank to the fuel pump (located inside the tank), and the supply line from the pump to the fuel injectors. Both are 5/16-inch diameter rubber hose on the original bike. When upgrading, you have two main paths: OEM Harley replacement lines (part numbers 61300-99A and 61301-99A, or similar depending on configuration) or aftermarket braided stainless steel kits designed for Road King models.
Braided stainless kits typically include pre-cut lines, stainless fittings, and hose clamps, and run $100 to $200 from Harley dealers, J&P Cycles, Drag Specialties, or RevZilla. OEM rubber replacements cost $40 to $80 per line but require you to source fittings separately if the originals are damaged. Braided lines last longer and resist cracking, but they are stiffer and require more careful routing around the frame and engine heat sources.
Draining the fuel tank safely
Before you touch any fuel lines, you must remove fuel from the tank. You have two options: drain it completely or siphon out enough to work safely. A full tank on a Road King holds about 5 gallons, so complete draining is the safest approach if you have time and a safe place to store fuel in an approved container.
To drain: turn the fuel petcock to the OFF position (or leave it OFF if your 2000 model has a vacuum-operated petcock), remove the fuel cap, and either use the drain plug on the bottom of the tank (if accessible on your model) or disconnect the fuel line at the carburetor or fuel rail and let fuel flow into a pan. If you siphon instead, use a hand-operated fuel pump or siphon kit — never mouth-siphon gasoline. Once the tank is empty or low, you can safely remove it by unbolting the two rear mounting bolts and the front mounting bracket, then carefully lifting it away from the frame.
Removing and replacing the fuel lines step by step
With the tank removed and drained, locate the fuel pump assembly on the underside of the tank. The inlet line connects to the pump pickup tube inside the tank; the outlet line exits the pump and runs to the fuel injectors. Both lines are held on with hose clamps and push-fit or barbed fittings.
Loosen the hose clamps with a screwdriver or socket wrench, then gently twist and pull the old line off the fitting. If the line is stuck, use a fuel line removal tool (a small plastic or metal collar that slides under the clamp and pops the line free) or carefully work it side to side. Once removed, inspect the fittings for damage; if they are corroded or cracked, replace them with new stainless fittings from your upgrade kit.
Slide the new braided line onto the fitting, ensuring it seats fully, then tighten the hose clamp snugly — not so tight that you crush the line, but tight enough that it does not slip. Repeat for the second line. Before reinstalling the tank, reconnect the fuel pump electrical connector and run the fuel pump briefly (key on, engine off) to check for leaks at both connection points. If you see fuel weeping, tighten the clamp slightly and retest.
Reinstalling the tank and testing for leaks
Once both lines are find and the pump test shows no leaks, carefully lower the fuel tank back onto the frame and align the mounting holes. Install the rear mounting bolts first, then the front bracket, and tighten all bolts snugly in a cross pattern to avoid warping the tank. Reconnect the fuel cap and the fuel petcock vacuum line (if applicable).
Refill the tank with fresh fuel and turn the key to ON without starting the engine. Listen for the fuel pump to run for a few seconds, then turn the key OFF. Inspect the fuel pump area and both line connections for any drips or fuel smell. Start the engine and let it idle for a minute, watching for leaks. If everything is dry and the engine runs smoothly, the upgrade is complete. If you see fuel leaking, turn off the engine when ready, locate the leak, and tighten the clamp or reseat the line.
Tools and materials you will need
Basic hand tools cover most of the job: a socket set (10mm and 12mm sockets are common for Road King tank bolts), screwdrivers (flathead and Phillips), an adjustable wrench, and pliers. A fuel line removal tool ($5 to $15) saves frustration if lines are stuck. You will also need an approved fuel storage container if you drain the tank completely, shop towels or rags, and a drain pan to catch any spilled fuel.
For the upgrade itself, gather your braided fuel line kit (or individual lines and fittings), new hose clamps if not included, and a fuel pump test tool or multimeter if you want to verify pump operation before reassembly. Many home mechanics skip the test tool and straightforward listen for the pump to run and watch for leaks, which works fine for this job.
Common mistakes and how to avoid them
The most frequent error is over-tightening hose clamps, which can crush braided lines and cause leaks. Tighten until snug, then stop; if the line still slips, the fitting may be worn and need replacement. Another common issue is forgetting to reconnect the fuel pump electrical connector before testing, which leaves you wondering why the pump does not run.
Routing braided lines carelessly can also cause problems: lines that touch hot exhaust pipes or sharp frame edges will wear through over time. Use the original line routing as a guide, and if you must deviate, find the line with cable ties or adhesive-backed clamps to keep it away from heat and sharp edges. Finally, do not rush the tank reinstallation; misaligned mounting bolts can crack the tank or cause fuel leaks from the seams.
Frequently Asked Questions
Can I upgrade just one fuel line, or do I need to replace both?
You can replace just the line that is failing, but most owners upgrade both at the same time since you already have the tank off and the second line is usually in similar condition. Doing both takes only an extra 15 minutes and prevents a second breakdown later.
What is the difference between braided stainless and reinforced rubber lines?
Braided stainless lines have a steel mesh exterior over an inner tube and resist cracking from heat and UV for 10+ years. Reinforced rubber lines are thicker than original rubber but still degrade over time; they cost less but do not last as long. Braided is the better long-term choice if budget allows.
Do I need to replace the fuel pump when I upgrade the lines?
No, the fuel pump itself does not need replacement unless it is failing (weak pressure, no flow, or electrical noise). Line upgrades are separate from pump service. If the pump is original and the bike has high mileage, you may want to inspect it while the tank is off, but replacement is not required for a line upgrade.
Will new fuel lines improve my Road King's performance?
New lines restore fuel flow if old lines were restricting it, which can improve cold starts and idle quality. However, if your bike runs fine, the upgrade is mainly preventive — you are avoiding future leaks and failures, not fixing a current performance problem.
Can I do this upgrade without removing the fuel tank?
Technically you can access the fuel pump inlet line without full tank removal on some Road King models, but it is awkward and risky. Removing the tank takes an extra 20 minutes but gives you clear access, better lighting, and room to work safely. Most home mechanics find full removal worth the time.