Harley-Davidson motorcycles are known for their raw power and iconic design, which makes them some of the most sought-after bikes in the world. But did you know that there’s a debate raging amongst Harley enthusiasts about which pushrod is longer – the intake or the exhaust? For many riders, this is a burning question that needs to be answered. So, let’s roll up our sleeves, dive into the mystery and see if we can settle this debate once and for all.
When it comes to Harley engines, the pushrods are an essential component that helps the engine run smoothly and efficiently. They operate the valves in the engine to allow fuel and air in and the exhaust gases out, which is why pushrods are vital to the engine’s overall performance. However, one issue has been causing confusion amongst Harley lovers for years – and that’s the question of whether the intake or exhaust pushrod is longer. Some claim that the intake pushrod is longer, while others maintain that the exhaust is the longer of the two. So, which one is it? Let’s find out.
Harley-Davidson enthusiasts are a passionate and knowledgeable group, but the debate over which pushrod is longer is one that has divided even the most devout of riders. To get to the bottom of this mystery, we’ll need to delve into the technical specs and explore the history of Harley engines to determine the answer once and for all. So, if you’re ready to deep-dive into the world of Harley mechanics, join us as we explore the length of the intake and exhaust pushrods and find out which one holds the title of the longest.
Harley Davidson Pushrod Length
Pushrods are an integral part of an engine’s valve train, and they are responsible for operating the valves. A pushrod is a metal rod that connects the camshaft to the rocker arms, which in turn opens and closes the valves. Every Harley Davidson motorcycle has two pushrods for each cylinder to operate the intake and exhaust valves. These pushrods have a crucial role in the operation of the engine, and their length determines certain engine characteristics.
Which Pushrod is Longer: Intake or Exhaust?
One of the common questions among Harley Davidson owners is which pushrod is longer, the intake, or the exhaust? The answer is that it depends on the model and the engine. However, in most Harley Davidson engines, the exhaust pushrod is longer than the intake pushrod. The reason for this is that the exhaust valve is usually located higher in the cylinder head than the intake valve. As a result, the rocker arm that operates the exhaust valve has to travel further, and a longer pushrod is required.
Why Does Pushrod Length Matter?
The length of the pushrod affects how the engine operates and performs. The pushrod length determines the valve lift, the amount of time the valve stays open, and the valve timing. Therefore, it is essential to use the correct pushrod length for the engine to achieve optimal performance. Pushrods that are too long or too short can cause the valves to open too early or close too late, resulting in low power and poor engine performance. Moreover, incorrect pushrod length can lead to premature wear on various engine components, resulting in costly repairs.
Harley Davidson Pushrod Length Chart
| Engine Model | Intake Pushrod | Exhaust Pushrod |
|---|---|---|
| Twin Cam 88 | 17427-99B | 17428-99B |
| Twin Cam 96 | 17920-03 | 17921-03 |
| Twin Cam 103 | 17369-06A | 17370-06A |
The chart above lists the Harley Davidson pushrod lengths for the Twin Cam 88, Twin Cam 96, and Twin Cam 103 engine models. The intake and exhaust pushrods have different part numbers and lengths for each engine model, so it is crucial to choose the correct pushrods when replacing them or adjusting the valve train. When in doubt, consult the Harley Davidson service manual or contact a certified mechanic.
Intake Pushrod Length
When it comes to Harley pushrods, there is often confusion around which one is longer – the intake or the exhaust pushrod. The answer is that it actually depends on the specific engine configuration, as different models and years of Harleys have varying pushrod lengths.
- The Evolution engine, which was in use from 1984 to 1999, has longer intake pushrods than exhaust pushrods. This is because the rocker arm ratio on the intake side is 1.625:1, while the exhaust side has a ratio of 1.5:1.
- In contrast, the Twin Cam engine, which was introduced in 1999 and is still in use on some Harley models today, has shorter intake pushrods than exhaust pushrods. This is because the newer engine has a more symmetrical rocker arm ratio of 1.625:1 on both sides.
- There are also aftermarket pushrods available for Harleys, which can come in varying lengths and materials depending on the specific needs of the rider and their bike.
It’s important to note that pushrod length can have an impact on engine performance, as it affects the valve timing and lift. If you’re experiencing issues with your Harley’s performance or are considering upgrading your engine, it’s important to consult with a knowledgeable mechanic or Harley expert to determine the best pushrod length for your specific bike and riding style.
| Engine Model | Intake Pushrod Length | Exhaust Pushrod Length |
|---|---|---|
| Evolution | 7.200 inches | 7.136 inches |
| Twin Cam | 6.885 inches | 7.194 inches |
Overall, understanding the nuances of Harley pushrods and their impact on engine performance can be a complex subject. But with the right knowledge and expertise, riders can make informed decisions about their bike upgrades and maintenance to ensure optimal performance on the road.
Exhaust Pushrod Length
When it comes to Harley pushrods, there are two main types: intake and exhaust. One question that many riders often ask is which pushrod is longer. While there isn’t a straightforward answer to this question, we can take a closer look at exhaust pushrod length and the factors that affect it.
- Material: The material that the pushrod is made of can affect its length. For example, aluminum pushrods tend to expand more than steel pushrods, which can result in a shorter overall length.
- Tolerance: The level of tolerance during manufacturing can also play a role in exhaust pushrod length. If the pushrod is manufactured with tighter tolerances, it may end up being slightly shorter than one with looser tolerances.
- Temperature: The temperature of the engine can also impact exhaust pushrod length. As the engine heats up, the metal components, including the pushrods, can expand. This expansion can cause the pushrods to become shorter.
While it may seem like a minor detail, the length of the exhaust pushrods can have a significant impact on a Harley’s performance. If the pushrods are too short, it can cause problems with valve timing and limit the engine’s power. On the other hand, if the pushrods are too long, it can result in excessive valve overlap, which can also negatively impact performance.
If you’re replacing the pushrods on your Harley or building a custom engine, it’s important to pay attention to the length of the exhaust pushrods. The table below outlines the stock exhaust pushrod lengths for various Harley engines:
| Engine Model | Exhaust Pushrod Length |
|---|---|
| Evolution | 7.435 inches |
| Twin Cam | 9.637 inches |
| Milwaukee-Eight | 11.623 inches |
Of course, if you’re building a custom engine or have modified your Harley in any way, these stock pushrod lengths may not be suitable for your needs. In these cases, it’s best to consult with a Harley mechanic or engine builder to determine the appropriate pushrod length for your specific setup.
Understanding Pushrod Length for Harley Davidson
Harley Davidson motorcycles are known for their iconic rumble and power. But behind that power lies a complex engine system, with the pushrod being one of the crucial components. A pushrod is a long, narrow component that connects the camshaft to the rocker arms and ultimately the valves. It is responsible for opening the valves at the right time, ensuring optimal fuel-air mixture and exhaust from the cylinder. In this article, we will explore pushrod length for Harley Davidson, particularly which pushrod is longer, intake or exhaust.
Why is Pushrod Length Important?
- Pushrod length is essential to the performance of the engine. A pushrod that is too long can lead to the valves opening too early or closing too late, resulting in reduced engine power and fuel economy. On the other hand, a pushrod that is too short can cause the valves to open too late and close too early, leading to reduced power and overheating.
- Pushrod length is also crucial when it comes to adjusting valve clearance. Adjusting the pushrod length can fine-tune the valve clearance, which is the gap between the valve stem and rocker arm. Valve clearance affects engine performance and emissions, so it is crucial to ensure that the pushrod length is appropriate.
- Lastly, pushrod length can impact overall engine health and longevity. Incorrect pushrod length can lead to valve train failures, which can cause extensive damage to the engine if left unchecked.
Are Intake or Exhaust Pushrods Longer?
Now, the big question – which pushrod is longer, intake or exhaust?
The answer is that it depends on the type of engine. In Harley Davidson engines, the exhaust pushrods are typically longer than the intake pushrods. However, there are exceptions, particularly in older engines or customized engines where the pushrod lengths can vary.
How to Choose the Right Pushrod Length?
Choosing the right pushrod length for your Harley Davidson engine requires careful consideration and professional assistance. Factors that determine pushrod length include the engine’s camshaft, valve train geometry, rocker arm ratio, and valve clearance. Moreover, pushrod length can also depend on the type of engine, the displacement, and the intended use.
| Pushrod Length | Result |
|---|---|
| Too Long | Reduced power and fuel economy, valve train damage, overheating |
| Too Short | Reduced power, overheating, valve train damage |
| Correct Length | Optimal engine performance and longevity, efficient fuel economy, and reliable valve train operation |
It’s important to note that pushrod length should always be adjusted by a professional mechanic who has experience working with Harley Davidson engines. This will ensure that the pushrod length is set correctly, contributing to efficient engine performance and reliable valve train operation.
In conclusion, pushrod length for Harley Davidson engines is a critical factor that can impact engine performance, emissions, and longevity. While the exhaust pushrods are usually longer than intake pushrods, choosing the correct pushrod length requires careful consideration of the engine’s camshaft, valve train geometry, rocker arm ratio, and valve clearance. Always consult with a professional mechanic to ensure that your pushrod length is set up correctly, contributing to reliable engine operation and longevity.
The Importance of Pushrod Length in Harley Davidson Engines
When it comes to Harley Davidson engines, even the smallest components can have a significant impact on performance. One such component is the pushrod, which plays a crucial role in controlling the valve train. Pushrods can vary in length, and the length of the pushrod can have a noticeable impact on engine performance. In this article, we’ll take a closer look at the importance of pushrod length in Harley Davidson engines, and explore some of the key considerations when selecting pushrods for your bike.
- The function of pushrods: Pushrods are a vital component of the valve train in a Harley Davidson engine. They are responsible for transmitting the motion from the camshaft to the rocker arms, which then opens and closes the valves. The length of the pushrod determines the amount of lift and duration of the valve opening, which in turn impacts the engine’s performance.
- Effects of pushrod length: The length of the pushrod can affect valve timing, which has a direct impact on the engine’s power and torque output. If the pushrod is too short, the valve may not open fully, resulting in poor performance. Conversely, if the pushrod is too long, the valve may stay open too long, leading to a loss of power and potentially damaging the valve or piston. It’s essential to choose the right pushrod length for your particular engine and performance goals.
- Selecting the right pushrod: When selecting pushrods for your Harley Davidson engine, there are several factors to consider. These include the camshaft profile, cylinder head design, and desired engine RPM range. Different types of pushrods, such as solid or adjustable, may also be appropriate for different engine configurations and performance goals.
If you’re considering upgrading or replacing your pushrods, it’s important to work with a knowledgeable mechanic or engine builder who can help you make the right choice. They can help you assess your engine’s needs and select pushrods that will optimize performance and reliability.
| Pushrod Type | Advantages | Disadvantages |
|---|---|---|
| Solid pushrods | Simple and reliable | May require occasional adjustment due to thermal expansion and contraction |
| Adjustable pushrods | Easy to adjust without removing the pushrod | More expensive and less durable than solid pushrods |
| Poly-lock pushrods | Allow for minute adjustments without removing the pushrods | More expensive and complex than other types of pushrods |
Overall, the length of the pushrod is a critical factor in Harley Davidson engine performance. By understanding the function of pushrods and selecting the right type and length for your engine, you can optimize power and reliability and get the most out of your Harley Davidson riding experience.
How to Determine Pushrod Length in a Harley Davidson
If you are working on your Harley Davidson, one of the things you might need to do is adjust the pushrod length. The pushrod is the part of the engine that connects the rocker arms to the lifters. A pushrod that is too long or too short can cause serious engine problems, so it is important to get it right. In this article, we will explain how to determine pushrod length in a Harley Davidson.
- Method 1: Measuring Stock Pushrods – If your Harley has stock pushrods, measuring the pushrod length is relatively easy. You can use a pushrod measuring tool, which is a long rod with a dial indicator on one end and a button on the other. Simply insert the tool into the pushrod tube and press the button against the lifter. The dial indicator will show you the length of the pushrod.
- Method 2: Adjustable Pushrods – If you have adjustable pushrods, the process is a bit more complicated. To determine the correct length, you will need to follow these steps:
- Remove the pushrods from the engine and extend them to their maximum length.
- Measure the length of the pushrods.
- Subtract the recommended preload from the length of the pushrods.
- Adjust the pushrods to the recommended length.
- Method 3: Pushrod Length Calculator – Another option is to use a pushrod length calculator. This is a tool that takes into account several variables, such as cam lift, rocker ratio, valve lift, and lifter diameter, to determine the correct pushrod length. This method is more accurate but requires more knowledge and expertise.
Now that you know the different methods for determining pushrod length, it is important to note that getting it right is crucial for the health of your engine. Make sure to follow the manufacturer’s recommendations and seek the help of a professional if you are unsure of what you are doing. A small mistake can have disastrous consequences.
| Variable | How to Measure |
|---|---|
| Cam Lift | Measure the lift of the camshaft at the valve using a degree wheel or a dial indicator. |
| Rocker Ratio | Measure the ratio of the rocker arm using a ratio checker or by dividing the length of the pushrod by the length of the valve stem. |
| Valve Lift | Measure the lift of the valve using a dial indicator. |
| Lifter Diameter | Measure the diameter of the lifter using a micrometer. |
By following these steps and taking into account the variables listed in the table, you should be able to determine the correct pushrod length for your Harley Davidson.
Common Issues with Pushrod Length in Harley Davidson Engines
If you own a Harley Davidson, you know that every component plays a crucial role in its performance. One of the key components that require proper attention is pushrods- a long steel rod that serves as a connection between the camshaft and rocker arm. There are two types of pushrods in Harley Davidson engines: intake and exhaust pushrods. But one of the most common issues with these pushrods is determining which one is longer- intake or exhaust. Let’s delve deep into this issue.
The Number 7 Subsection: Intake vs. Exhaust Pushrod Length
- Before you can understand which pushrod is longer, you need to understand the difference between intake and exhaust pushrods. Intake pushrods are responsible for opening the intake valve, allowing air/fuel to enter the combustion chamber. Exhaust pushrods, on the other hand, are responsible for opening the exhaust valve, letting the burnt gases out.
- The intake pushrod is shorter than the exhaust pushrod in Harley Davidson engines. This is because the intake valve is located closest to the camshaft, and there is a lesser distance for the pushrod to cover. The exhaust valve is located further away from the camshaft, increasing the distance for the pushrod to cover. Therefore, the exhaust pushrod is longer in length.
- In certain cases, if you install the wrong pushrod, the valve lift and duration can be changed, leading to problems like backfiring, reduced power, and poor fuel economy. Therefore, it’s always crucial to use the right pushrod based on the manufacturer’s specifications.
Other Common Issues with Pushrod Length
While determining the length of the pushrods is a crucial aspect, there are other issues with pushrods that can cause problems in Harley Davidson engines. Let’s discuss them briefly.
- Pushrod Flex: The pushrod flexes under heavy loads, reducing the accuracy of the valve lift and duration.
- Pushrod Length Variations: Even a slight variation in pushrod length can lead to inaccurate valve timing and lift, which can cause engine damage over time.
- Pushrod Composition: Using substandard pushrods can lead to bending, snapping, or even breaking under high loads.
The Bottom Line
The pushrods may be a small component, but they play a crucial role in maintaining an engine’s performance. Whether it’s determining the length of pushrods or choosing the right pushrods for your Harley Davidson, make sure to consult with a professional mechanic to avoid expensive repairs and maintenance.
| Harley Davidson Engine | Intake Pushrod Length (inches) | Exhaust Pushrod Length (inches) |
|---|---|---|
| Twin Cam 88 (1999-2006) | 7.850 | 8.283 |
| Twin Cam 96 (2007 and later) | 7.850 | 8.283 |
| Twin Cam 103 (2010 and later) | 7.849 | 8.258 |
The table above shows the intake and exhaust pushrod lengths for various Harley Davidson engines. Make sure to use the right pushrod length based on the manufacturer’s specifications to avoid any engine damage.
Which Harley Pushrod is Longer, Intake or Exhaust?
Q: What is a pushrod in a Harley engine?
A pushrod is a mechanical device that transmits the motion of the camshaft to the valves of a Harley engine.
Q: Why do people ask which Harley pushrod is longer, intake or exhaust?
People ask this question because there is a common myth that Harley Davidson motorcycles have different length pushrods for intake and exhaust valves.
Q: Is there any truth to the myth?
No, there is no truth to the myth. All Harley Davidson motorcycles have the same length pushrods for intake and exhaust valves.
Q: Can changing the length of pushrods affect the performance of a Harley engine?
Yes, changing the length of pushrods can affect the performance of a Harley engine. It can increase or decrease the valve lift and duration, resulting in changes in the engine’s power and torque.
Q: Can a novice mechanic change pushrods?
Changing pushrods requires advanced knowledge and skill. It is recommended that only experienced mechanics with specialized tools perform pushrod replacement or adjustment.
Q: What happens if pushrods fail?
If pushrods fail, the engine will experience a loss of power and compression, and it may even stop running entirely.
Q: Can regular maintenance prevent pushrod failure?
Yes, regular maintenance such as oil changes, valve adjustments, and inspection can prevent pushrod failure and ensure the longevity and performance of the engine.
Thank You for Reading!
Now that you know the truth about pushrod length in Harley Davidson motorcycles, we hope you feel more confident in caring for your engine. Remember to stay on top of your regular maintenance and leave more complex tasks to experienced mechanics. Come back soon for more motorcycle-related articles and tips!