Harley Twin Cam Years to Avoid: A Comprehensive Guide

Last Updated on January 12, 2024 by Pittalks

Welcome to our in-depth guide on Harley Twin Cam engines, where we unravel the mysteries of which years and models to steer clear of and why. Harley-Davidson motorcycles are renowned for their performance and iconic status, but like any mechanical marvel, they have their quirks. In this article, we delve deep into the Twin Cam engine, highlighting the years to avoid and providing invaluable tips for potential buyers and current owners.

Understanding the Twin Cam Engine

Here's a picture of a Twin Cam engine from Harley Davidson.
This particular example is a 88ci variation of the Twin Cam engine.

The Twin Cam engine, introduced by Harley-Davidson in 1999, marked a significant evolution in motorcycle engineering. Renowned for its power and reliability, this engine quickly became a staple in many Harley models. However, not all Twin Cam engines are created equal. Let’s take a closer look at what makes this engine unique and why some years are better avoided.

Brief History and Introduction

  • 1999: Introduction of the Twin Cam engine.
  • 2006: Introduction of hydraulic cam chain tensioners to address tensioner issues.

Significance in Harley-Davidson Lineup

  • Dominant presence in Harley models for over a decade.
  • Known for enhancing performance and rider experience.

Known Issues and Years to Avoid

While the Twin Cam engine has many admirers, it’s crucial to be aware of the years and models that have known issues. Below is a detailed breakdown of the problems and the affected years.

Related: Is The Twin Cam 96 A Good Motor? Yes, No, Maybe So

Cam Chain Tensioner System Issue

  • Affected Years: 1999 – 2006
  • Problem: Original design with plastic shoes led to rapid wear and tear, potentially causing engine seizure.
  • Models Affected: Various, including Electra Glide, Dyna, Sportster, and Softail series.

High Crank Runout

  • Affected Years: 2003 – 2006
  • Problem: Misalignment in the crank assembly, leading to excessive side-to-side movement and potential engine failure.
  • Models Affected: Specific information required.

Piston Recoil Issues

  • Affected Model: Twin Cam 96 (introduced in 2007)
  • Problem: Smoke blowing out of the air filter, indicating potential issues.

Impact on the Oil Cooling System

The oil cooling system plays a pivotal role in ensuring your Harley runs smoothly. Here’s how the Twin Cam engine issues can take a toll on it:

  • Inadequate Lubrication: Blockages from degraded tensioner shoes can lead to poor lubrication, causing friction and potential damage.
  • Overheating: Reduced oil flow can cause the engine to overheat, leading to severe issues.

Tips for Purchasing a Twin Cam Harley Davidson

Buying a used Harley-Davidson requires diligence, especially if it’s equipped with a Twin Cam engine. Here are some tips to help you make an informed decision:

  • Check for Tensioner Upgrades: Ensure the cam chain tensioner system has been upgraded, particularly in models from 1999 to 2006.
  • Research Specific Models: Look into common issues or recalls associated with the specific model and year you are interested in.
  • Invest in Quality Oils and Cooling Systems: Protect your investment and enhance the longevity of your motorcycle.

Related: What Year Harleys to Avoid (A Comprehensive Guide)


The Twin Cam engine is a significant chapter in Harley-Davidson’s storied history, offering power and performance that many riders adore. However, being aware of the potential issues and the years to avoid can save you from future headaches. Armed with this knowledge, you can confidently navigate the world of Harley-Davidson motorcycles, ensuring many smooth rides ahead.

Lets dive deeper:
Twin Cam 88 vs 96: Which TC Is Really The King?
Twin Cam vs Milwaukee 8: Who’s The Harley Engine King?

Frequently Asked Questions

What is the Harley Twin Cam engine?

The Harley Twin Cam engine is a motorcycle engine designed and manufactured by Harley-Davidson. Introduced in 1999, it is known for its power and reliability, becoming a popular choice for many Harley-Davidson motorcycle models.

Why are certain years of the Harley Twin Cam engine advised to be avoided?

Certain years of the Harley Twin Cam engine, particularly from 1999 to 2006, are advised to be avoided due to known issues with the cam chain tensioner system. This system had a design flaw that could lead to rapid wear and tear, potentially causing serious engine damage.

Were all Harley-Davidson models affected by the Twin Cam engine issues?

Yes, various Harley-Davidson models, including the Electra Glide, Dyna, Sportster, and Softail series, were affected by the Twin Cam engine issues.

Are there any other common issues with the Harley Twin Cam engine?

In addition to the cam chain tensioner issue, some Twin Cam engines, particularly from 2003 to 2006, experienced high crank runout, leading to excessive side-to-side movement of the crankshaft and potential engine damage. The Twin Cam 96 model also had reported issues of piston recoil, resulting in smoke blowing out of the air filter.

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