1999–2005 Harley-Davidson Dyna Twin Cam 88 (FXDWG Wide Glide)

The 1999–2005 Harley-Davidson Dyna Twin Cam 88 (FXDWG Wide Glide) marked a significant era for the American motorcycle manufacturer, introducing a new engine platform to one of its most iconic factory-custom models. The Wide Glide, known for its chopper-inspired aesthetics, was a cornerstone of the Dyna family, and its transition from the venerable Evolution engine to the new Twin Cam 88 brought enhanced performance and refinement. This generation solidified the FXDWG’s reputation as a motorcycle that offered custom styling straight from the showroom floor, combined with the ride quality and engineering of the modern Dyna chassis.

The Introduction of the Twin Cam 88 Engine

The most substantial update for the 1999 model year was the replacement of the 1340cc (82 cu in) Evolution engine with the all-new 1450cc (88 cu in) Twin Cam 88. This engine was a major engineering step for Harley-Davidson. As its name implies, the “Twin Cam” featured two chain-driven camshafts in the crankcase (one for each cylinder), a departure from the single camshaft design of the preceding Evolution engine.

This new design allowed for more aggressive valve timing, improved airflow, and higher RPM potential. The engine also featured larger cooling fins for better heat dissipation and an internal oil pump system that improved lubrication and engine longevity. The result was a noticeable increase in both horsepower and torque, providing riders with stronger acceleration and better highway passing power. While the new engine was a leap forward, early models (1999-2000) utilized a specific crankshaft main bearing that was later updated. Over its lifespan, the Twin Cam 88 in the Dyna platform earned a reputation for reliability and was a popular base for performance modifications.

Dyna Chassis and Distinctive Wide Glide Styling

The FXDWG Wide Glide was built on Harley-Davidson’s Dyna frame, which was distinguished by its use of rubber engine mounts. This design isolated the rider from the V-twin engine’s vibrations, offering a smoother ride compared to the rigidly mounted Softail frame. However, it still retained a direct and connected feel that Dyna enthusiasts appreciated.

The styling of the FXDWG was its primary draw. It was designed to emulate the choppers of the 1970s and featured several key characteristics:

Wide Front End: The model’s name comes from its wide-raked front forks and wide triple clamps, which accommodated a skinny 21-inch laced front wheel, creating a classic chopper stance.
Forward Controls: Footpegs and controls were mounted far forward, stretching the rider into a relaxed, “feet-forward” cruising position.
Custom Aesthetics: A factory-installed “bobtail” rear fender, mini ape-hanger handlebars, a stepped two-up seat, and a fuel tank-mounted speedometer console completed the custom look.

Engine and Drivetrain: The primary difference was the move from the 1340cc Evolution engine to the 1450cc Twin Cam 88. This brought a significant performance boost of roughly 15-20% in both horsepower and torque. The transmission case was also redesigned to bolt directly to the new engine, creating a more rigid and unified powertrain assembly compared to the separate components of the Evolution era.
Chassis and Frame: While retaining the core Dyna design principles, the frame was updated to accommodate the dimensions and mounting points of the Twin Cam engine.
Fuel and Ignition System: For this generation, the FXDWG Wide Glide exclusively used a 40mm Keihin constant-velocity (CV) carburetor. This was paired with an updated electronic ignition system that was more advanced than the systems used on most late-model Evolution bikes.
* Braking: The braking system was improved for the Twin Cam models, featuring updated calipers that offered better stopping power to match the engine’s increased performance.

Throughout its 1999-2005 production run, the FXDWG Wide Glide saw only minor changes, mostly related to paint schemes, graphics, and slight component updates. The model remained largely true to its original 1999 design until the entire Dyna platform was overhauled in 2006, which introduced a new 6-speed transmission and a stiffer frame.

Technical Specifications (2003 FXDWG Wide Glide)