How To Adjust Idle On Fuel Injected Harley Davidson?

Many Harley Davidson models are now fuel injected, requiring a little different maintenance than carbureted models. One thing you may need to do from time to time is adjust the idle. 

If you own a fuel-injected Harley Davidson, you may find that you need to adjust the idle from time to time. This relatively easy task can be done in just a few minutes. 

To adjust the idle on a fuel-injected Harley Davidson, locate the idle speed adjustment screw on the throttle body. Start the motorcycle and let it warm up. Use a screwdriver to turn the adjustment screw clockwise to increase idle speed or counterclockwise to decrease it. Aim for a smooth and stable idle around 900-1,000 RPM.

If you’re not sure how to do this, never fear! This blog post will walk you through the step-by-step process and everything you need to know about it so let’s start!

Ways to adjust idle

There are three ways to adjust the idle on your fuel-injected Harley Davidson motorcycle. 

  1. With speed screw located on the throttle body
  2. By adjusting the throttle position sensor (TPS)
  3. Manually by opening or closing the throttle body butterflies

How To Adjust Idle on Fuel-Injected Harley Davidson?

1. With speed screw located on the throttle body

The most common way to adjust the idle on a fuel-injected motorcycle is to adjust the idle speed screw located on the throttle body. 

Step 1: To do this, you will need a Phillips head screwdriver

Step 2: Start by locating the idle speed screw on the throttle body. 

Step 3: It is usually located on the side of the throttle body near the air filter housing. 

Step 4: Once you have found the idle speed screw, turn it clockwise to increase the idle speed or turn it counterclockwise to decrease the idle speed. 

Step 5: Turn the screw 1/4 turn at a time and then check the idle speed. 

Step 6: Repeat this process until you have the desired idle speed.

2. By adjusting the throttle position sensor (TPS)

Step 1: Find the TPS on your Harley Davidson. It is located on the back of the throttle body.

Step 2: Unplug the electrical connector from the TPS.

Step 3: Use a flathead screwdriver to turn the TPS clockwise or counterclockwise until you find the sweet spot. The sweet spot is when the engine idles smoothly.

Step 4: Once you find the sweet spot, plug the electrical connector back into the TPS.

Step 5: Start the engine and let it idle for a few minutes to ensure the adjustment succeeded.

If you’re having trouble finding the sweet spot, it’s smart to take your Harley Davidson to a mechanic or dealership who can help you adjust the TPS. Improperly adjusting the TPS can cause your engine to run poorly or even damage it.

When the Harley is running too lean (or too rich), it’s possible to adjust the idle mixture by opening or closing the throttle body butterflies. This step-by-step guide will show you how to do it.

3. Manually by opening or closing the throttle body butterflies

Step 1: Warm up your Harley until the engine temperature is at the normal operating level. This is significant because the idle mixture screws are temperature sensitive.

Step 2: Locate these screws on the throttle body. On most models, they will be on the front or back of the throttle body.

Step 3: Using a small screwdriver, turn both screws clockwise until they stop. This is the starting point.

Step 4: Turn both screws counterclockwise for 1 1/2 turns.

Step 5: Start the engine and let it idle. If the idle is too high, turn both screws clockwise until it drops to the desired level. If the idle is too low, turn both screws counterclockwise until it rises to the desired level.

Step 6: Once the idle is set, turn both screws clockwise and 1/4 turn. This will help prevent the screws from vibrating loose.

Step 7: Test-ride your Harley to ensure the idle mixture is still set correctly. If not, repeat the process until is.

Why do we need to Adjust the Idle On Fuel Injected Harley Davidson?

Your Harley Davidson has a fuel injection system that needs to be adjusted from time to time. This is because the fuel mixture can change, and the idle speed can change as well.

Also, to ensure that the engine is running at the correct RPM the idle on a fuel-injected Harley Davidson needs to be adjusted. If the idle is too low, the engine will stall. If the idle is too high, the engine will consume more fuel than necessary.

Additionally, excessive emissions can damage engines and harm the environment. Adjusting the idle also helps improve fuel efficiency.

Overall, properly adjusting the idle on a fuel-injected Harley Davidson can benefit the bike and its rider. It is important to regularly check and adjust the idle, as factors such as weather conditions and engine wear can affect its settings.

When to Adjust Idle on Fuel-Injected Harley Davidson?

The right time to adjust the idle on a fuel-injected Harley Davidson is after the engine has been warmed up. Allowing the engine to idle too long can also cause problems with starting and running.

If you are having difficulty getting the engine to idle correctly, it is prudent to take it to a qualified mechanic or Harley Davidson dealership. 

Many factors can affect the idle on fuel-injected Harley Davidson including air intake, exhaust, and fuel delivery. A qualified technician will be able to diagnose and fix any issues you may be having properly.

The ideal operating temperature for a Harley Davidson is between 160-170 degrees Fahrenheit. If the engine is too cold, it will not run as efficiently and may cause starting and running problems.

Conversely, if the engine is too hot, it can damage the engine. Allowing the engine to idle too long can also cause problems with starting and running.

What are some tips for adjusting the idle on fuel-injected Harley-Davidsons?

  1. Harley Davidson recommends that you check the air filter and make sure it is clean and that the air filter element is not oily. If it is, replace the filter.
  2. Make sure the throttle valve cables are adjusted properly and are not binding.
  3. Make sure the idle mixture screws are adjusted correctly.
  4. Make sure the engine is at operating temperature before adjusting the idle speed.
  5. Adjust the idle speed screw until the desired idle speed is achieved.
  6. Check for vacuum leaks if the engine is still idling too high or low.
  7. Keep track of engine wear and replace worn components as needed.
  8. If the problem persists, take the motorcycle to a qualified Harley Davidson dealer for diagnosis and repair.
  9. Never try to adjust the throttle valves while the engine is running. Doing so could result in serious injury or death.

What if my Harley won’t idle?

If your Harley won’t idle, it could be a sign of a bigger problem. Try troubleshooting by checking the following:

1. You should check the air filter to see if it is clean. Dirty air filters can restrict airflow and cause the engine to run lean, leading to a variety of problems.

2. Replace the spark plugs if necessary. Misfires can result from worn-out spark plugs, causing the engine to run rough.

3. Check the fuel system to see if there are any leaks. A fuel leak can cause the engine to run lean, leading to various problems.

4. See if the throttle position sensor is functioning properly. The engine can run rough or stall when the throttle position sensor is faulty.

5. Check the engine temperature sensor to see if it’s working properly. A faulty engine temperature sensor can cause the engine to run hot, leading to various problems.

If you can’t find the source of the problem, it’s best to take your Harley to a qualified mechanic for further diagnosis and repair.

What Revolutions per minute should a Harley idle at?

According to Harley-Davidson, the recommended idle RPM for their engines is 950. However, some engines may idle slightly higher or lower than this they can reach 1050 RPM. It’s important to note that allowing the engine to idle too low can result in rough running and potential damage.

On the other hand, idling too high can cause excessive engine wear and increased emissions. It’s best to maintain the recommended idle RPM as much as possible. If you notice that your Harley is idling too high or too low, it may be a sign of an issue with the engine and it’s best to have it checked by a professional mechanic.

FAQs

Verdict:

By following these methods, you can easily adjust the idle on your fuel-injected Harley Davidson. Be sure to take a test ride after making any adjustments to ensure that the updated settings are working properly. With just a few minutes of your time, you can keep your Harley running smoothly for years to come!

That’s all there is to adjust the idle on a fuel-injected Harley Davidson! If you have questions or concerns, feel free to take your bike to your local service center for assistance. Thanks for reading!

About David Riedel

I am David Riedel founder of Bikerwhizz, I'm a technician at Keystone Harley Davidson with more than 10 years of industry experience. I’m here to help you solve motorbike problems, customizations, tweaks, and easy fixes to enjoy your rides more.

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