Classic Motorcycle Build

Wide Glide Conversion

Article by Mark Trotta

Originally offered on the FXWG in 1980, Harley Wide Glide forks and triple trees are a simple bolt-on conversion to most other Harley-Davidson motorcycles, including Panheads, Shovelheads, and Servi-car trikes.

Wide Glide conversion

In addition to the FXWG models, Wide Glide front ends were also fitted to 1980-1983 FWDG Dyna models, and several Softail models from 1993-2003.

Because all Harley Big-Twin frames from 1949-up have the same 1.00" neck diameter, the Wide Glide conversion has become a popular front end swap.

Wide Glide Front-End Specs

The original Wide Glide front forks measured 1-5/8" in diameter. Somewhere in the eighties, the Motor Company started farming out forks overseas and began the listing of fork diameter in millimeters instead of inches. Since then, fork diameter has been referred to as 41mm.

The spacing dimension for Wide Glide forks is 9.875" between fork tube centers. By comparison, a 'Mid-Glide' is 8.875" between fork tube centers, and a 'Narrow-Glide' is 7.00" between fork tube centers.

Harley Wide Glide conversion

Early Wide Glide models had dual disc front brakes. Later models had a single-disc brake with a single-piston caliper.

In 2000, dual four-piston calipers were fitted, which made a substantial difference in braking. The 2000-up Wide-Glide front wheel hub was upgraded with sealed bearings.

Front Axle Diameter

Depending on what year and model motorcycle, front wheel axle size will vary. Starting in 2000, Harley went to 1" front axle bearings on touring bikes. In 2008, they went to a 25.8mm bearing, which is a fraction of an inch different.

The sliders are the same for the 1" and the 25.8mm axles, but the bearings, spacers, and axles changed. There are different kits available so you can switch to the appropriate bearings needed.

Harley Triple-Tree Identification

Before starting a Wide Glide conversion, take note of the fork stops (the short nubs on the lower triple-tree that bump against the steering tube). Watch for nubs that have been sheared off, an indicator of accident damage.

Wide Glide front end swap

The 1987 or so FX models had a steel lower tree, but the rest are aluminum. Softail Wide Glide trees and the ones for FXDWG are slightly different on the fork stop.

Wide Glide front end lower tree

Some forks have mounts on the sides of the upper and lower trees for mounting the aluminum headlight tins. The nacelle unit will use a spacer ring to adjust the headlight position.

Factory vs Aftermarket

The aftermarket for stock replacement and custom hydraulic forks is huge, making a Wide Glide conversion complete if missing parts. There are literally hundreds of different tree-fork combinations from dozens of companies that you can buy ranging from low-end stock assemblies to complete custom fabrications.

Wide Glide forks, tubes, and trees are all produced in the aftermarket by various suppliers. Mostly chrome units are offered. Some triple tree sets use a lower tree with the mounts shaved off for custom applications.

Wide Glide conversion

The Wide Glide front end in the above picture appears to be a pre-2000 single-disc with 41mm fork tubes, H-D part # 45674-80c. The '80' tells it is a 1980 year beginning manufacture part, but remember that Harley puts production numbers on a lot of parts that aren't actual part numbers.


Conversion Kit For 1984-1999 Narrow Glide models

Here's a narrow to wide glide conversion kit that allows use of narrow glide 19" or 21" wheel (found on FX, FXR, FXD and XL models) to be installed in a 41mm Wide Glide front end. The kit includes an aluminum disc spacer (second spacer for dual disc available), socket head screws, axle spacer and 3/4" axle.

Wide Glide conversion

Shop: 1984-1999 Narrow-To-Wide Glide Wheel Conversion Kit


Wide Glide Conversion To Sportster

From 1957 through 1977, Sportsters had a 7/8" neck, and 1978 through 1981 Sportsters had a 15/16" neck. In 1982, Harley standardized neck sizes, and 1982 and up Sportsters have a 1" neck like all Big-Twin models.

If you're considering converting your pre-1982 Sportster to a Wide Glide front end, there are no factory triple trees that will fit the 7/8" or 15/16" necks. The best way would be finding an aftermarket kit, but we don't know of one that is presently available.


19" vs 21" Front Wheel

The 21" front wheel from Harley came with either a 2.15" or 3.5" width tire. The wider tire will give slightly improved handling and a bit more stability. If you like to throw you bike into a corner, a 19" wheel will handle better than a 21" wheel.

If you are running a front fender with either the 19" or 21" wheel, several aftermarket companies offer fender spacers to permit use of your stock fender.


I installed a Wide Glide front end on my 1961 Harley Servi-car. It will allow me to run a front disc brake instead of the original drum brake.

Harley-Davidson Servi-car restoration

The front tire is a 21".


What Weight Fork Oil Is Best?

If you ride during winter months, 10W fork oil is better for colder conditions, and 30W is better for very hot weather conditions. For average temperature conditions, you can use 20W fork oil. It's always best to check the factory manual for your exact year, make, and model motorcycle.

motorcycle fork oil

Shop: Fork Oil

Factory service manuals state that fork oil should be changed every other riding season, but it also depends on how much (or how little) you ride.


Below are Wide Glide fork oil capacities:

9.0 to 10.2 Oz..... FXWG/FXST 1980-84

10.2 to 11.2 Oz..... FXWG/FXST 1985-2006

10.2 to 11.2 Oz..... Dyna Wide Glide 1991-2005

TIP: An easy way to measure fork oil is to push the forks down all the way while the caps are off, and fill it to 5" below the upper edge of the fork tubes.


Related Articles:

Harley Forks Identification
1977-1983 Harley Dual Caliper Rebuild
Replace Fork Seals 35mm
Install Gas Tank on Hardtail Frame
Harley Wide Glide front end

Read: Wiring A Motorcycle From Scratch