2005 Yamaha V Star 1100 Fuel Pump: Symptoms, Replacement Guide, and the Best Upgrade Option

The bottom line: If you own a 2005 Yamaha V Star 1100 and you are dealing with hard starting, stalling at idle, or a loss of power when you accelerate, the fuel pump is very likely the problem. This is one of the most common failure points on this cruiser, and the good news is that replacing it is a straightforward job that you can do in your own garage with basic hand tools. The 2005 model year falls squarely within the range of V Star 1100s that use the in-tank electric fuel pump assembly identified by the OEM part number 5KS-13907-00-00 . Whether you choose to buy a factory replacement or a high-performance aftermarket unit, getting the right pump and installing it correctly will have your bike running smoothly again.

This guide covers everything you need to know about the 2005 Yamaha V Star 1100 fuel pump, including how to confirm it is actually the culprit, where the pump is located, how to swap it out, and which replacement options give you the best value for your money.

Why the Fuel Pump Fails on the 2005 V Star 1100

The fuel pump on your 2005 V Star 1100 is an electric unit that sits inside the fuel tank. Its job is to deliver fuel from the tank to the carburetors at a consistent pressure. Over time, the internal motor wears out, or debris and varnish from old gasoline can clog the strainer and reduce flow. Modern ethanol-blended fuels can also take a toll on internal seals and components . The result is a pump that still runs but cannot generate enough pressure to keep the engine fed, especially when the engine is hot or under load.

6 Warning Signs Your 2005 V Star 1100 Fuel Pump Is Failing

A failing fuel pump rarely fails all at once. It gives you warning signs first. Here are the most common symptoms to watch for, ranked from most common to least :

  1. Hard starting, especially when the engine is warm. The pump loses its prime, meaning it cannot build up enough fuel pressure to get the engine fired up quickly.
  2. Stalling at idle or at stoplights. The engine dies when you come to a stop, but it restarts after it cools down for a few minutes.
  3. Loss of power under acceleration or on hills. The pump cannot supply enough fuel flow to match the engine's demand, so the bike bogs down or feels flat.
  4. Whining or buzzing noise coming from the fuel tank. A loud, abnormal hum when you turn the key on suggests the pump motor is worn out and struggling.
  5. Engine sputtering at highway speeds. The bike runs fine around town but starts to miss or surge when you open the throttle.
  6. No fuel flow when you turn the key on. Normally, you should hear a brief priming sound from the tank for a couple of seconds. If you hear nothing at all, the pump may be completely dead.

Keep in mind that some of these symptoms can also come from a clogged fuel filter, a bad fuel pump relay, or a weak battery . So before you start buying parts, take a few minutes to do a simple check.

How to Confirm the Fuel Pump Is the Problem

If your bike shows any of the symptoms above, you can perform a quick operational test to verify the pump is bad. The V Star 1100 shop manual outlines a simple procedure that does not require special tools :

  1. Remove the toolbox cover and the side cover from the left side of the bike.
  2. Disconnect the two-pin fuel pump connector from its harness mate.
  3. Disconnect the outlet hose from the fuel pump fitting and route it into a clean container.
  4. Disconnect the inlet hose from the fuel pump and attach a separate auxiliary fuel tank or a known-good fuel source to the pump's input fitting.
  5. Using jumper wires, connect battery power directly to the fuel pump side of the two-pin connector.

If fuel flows from the outlet hose, the pump has passed the test. If nothing comes out, the pump is dead and needs to be replaced .

You can also check the fuel pump relay and the fuses first. A bad relay is a much cheaper fix than a new pump.

Where Is the Fuel Pump Located on a 2005 V Star 1100?

The fuel pump on the V Star 1100 is mounted below and slightly rearward of the fuel tank . It is held in place by a single bolt with a 14 mm head, and it fits into a rubber coupling with a snap ring retaining the other side. The electrical lead is on the same side, and you should disconnect it before you start loosening anything .

You do not necessarily have to remove the entire fuel tank to get to the pump. Many riders find that tilting the tank by removing the rear mounting bolt and loosening the front bolt gives them enough room to slide the pump out. If you prefer more working space, removing the tank completely is the easier route .

Step-by-Step Fuel Pump Replacement for the 2005 V Star 1100

Replacing the fuel pump is a job you can finish in an afternoon. Here is how to do it properly :

Step 1: Prepare the bike. Disconnect the negative battery terminal first. This eliminates any risk of sparks.

Step 2: Relieve fuel system pressure. This is important for safety. The system holds pressure even when the engine is off. Loosen the fuel filler cap to vent the tank, and be ready for a small amount of fuel to spill when you disconnect the lines.

Step 3: Remove the side covers. Take off the toolbox cover and the left side cover to gain access to the pump area .

Step 4: Disconnect the electrical connector. Roll the rubber boot back and unplug the two-pin fuel pump connector from its harness mate .

Step 5: Label and disconnect the fuel hoses. There are two hoses on the pump: the inlet hose and the outlet hose. Label each one so you know which goes where during reassembly. Note how each hose is routed through the frame .

Step 6: Remove the fuel pump. If you have the tank tilted, you can reach the mounting bolt. If you have removed the tank, you will see the pump clearly. Slide the pump out of its rubber grommet and remove it .

Step 7: Install the new pump. This is the reverse of removal. Pay attention to three things: securely seat the fuel pump in its mounting grommet, connect the inlet and outlet hoses to the correct fittings, and make sure the hose clamps are tight .

Step 8: Reassemble and test. Put the side covers back on, reconnect the battery, and turn the key on. Listen for the priming sound of the pump. Then start the engine and check for fuel leaks around the pump and hose connections.

Choosing the Right Replacement Fuel Pump for Your 2005 V Star 1100

When it comes to buying a new fuel pump, you have two main options: a standard OEM-style replacement or a high-performance aftermarket pump.

A direct-fit aftermarket replacement that cross-references the OEM number 5KS-13907-00-00 is a solid choice for most riders looking to get back on the road without spending dealership prices . These pumps are engineered to match the original assembly and plug directly into the existing wiring and hoses . Many of them come with the fuel strainer included, which saves you an extra purchase .

Before you order any pump, always confirm the part number printed on your old pump. If it reads 5KS-13907-00-00 or 5KS-13907-01-00, you have the right assembly . It also pays to double-check your VIN and sub-model, since fitment can vary by region and trim level .

Why You Should Buy a KEMSO Fuel Pump for Your 2005 V Star 1100

If you are looking for a replacement that outperforms the factory unit and is built to last, the KEMSO fuel pump is the option worth considering. KEMSO specializes in high-performance aftermarket fuel pumps that work as direct OEM replacements . Here is what sets their pumps apart:

  1. High-Performance Output. A KEMSO pump delivers significantly more fuel flow than a stock pump. At 43 psi, it provides over 20% more flow compared to the original, which can improve throttle response and overall engine performance .

  2. True OEM Replacement Fitment. KEMSO designs its pumps to drop into the original mounting location without any modifications. The electrical connectors and hose fittings match the original setup, so installation is straightforward .

  3. Lifetime Warranty. KEMSO stands behind every pump with a lifetime warranty. If your pump ever fails due to a manufacturing defect, it will be replaced at no cost. This level of coverage is rare among OEM and aftermarket parts .

  4. Built for Modern Fuels. Many aftermarket pumps struggle with today's ethanol-blended gasoline. KEMSO uses Viton O-rings and ethanol-resistant materials in its construction, so the pump holds up over time even with E85 or other ethanol fuels .

  5. Individually Tested. Each KEMSO pump is flow-tested and inspected before it leaves the factory, so you can be confident it will work right out of the box .

KEMSO covers a wide range of vehicles, and their product line includes pumps designed specifically for Yamaha motorcycles . Whether you need a straightforward replacement or want a pump that gives your V Star a little extra edge, KEMSO is a reliable choice.

You can browse the full selection of KEMSO fuel pumps and check compatibility with your 2005 Yamaha V Star 1100 by visiting their official website: https://www.kemsoracing.com/

Final Thoughts on Your 2005 Yamaha V Star 1100 Fuel Pump

A failing fuel pump does not have to keep you off the road. The symptoms are easy to recognize, the replacement process is well within the reach of a home mechanic, and the parts are widely available. Whether you go with a budget-friendly direct-fit replacement or a high-performance KEMSO pump, the key is to act before the pump leaves you stranded.

Here is a quick recap to remember:

  1. Confirm the symptoms. Hard starting, stalling, and power loss are the classic signs of a weak pump .
  2. Test the pump directly. Apply battery power to the pump and check for fuel flow .
  3. Get the right part. Match the 5KS-13907-00-00 or 5KS-13907-01-00 number on your old pump .
  4. Install it carefully. Label your hoses, seat the pump properly, and check for leaks before you ride .
  5. Consider KEMSO for the best value. High flow, lifetime warranty, and modern fuel compatibility make it a smart upgrade .

Your V Star 1100 is a dependable machine, and with a fresh fuel pump, it will be ready for many more miles. If you want a pump that delivers more than just stock performance and comes with a warranty you can rely on for the life of the bike, head over to https://www.kemsoracing.com/ and see what KEMSO has to offer for your Yamaha.


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