The DAVIDSON CODE

Decoding the Harley Letter Codes

It seems like the Harley Model Codes used to be fairly simple, but over the last few years, they have strayed from "logical" to "what letters have we not used yet". HAHA!! :-)

Each letter in the code stands for something, but sometimes they use a pair of letters, and then there will be suffixes, so think of "blocks" rather than letter number when we mention which letter we're talking about.

Harley makes two types of engines and three frames, then outfits the different frames differently, for touring or cruising or whatever.
 

The first letter is the engine type.
F - is the Big Twin engine. Doesn't matter the size, big twins are any engine that has been designed without the transmission/primary being an integral/internal part of the engine crankcase.
X - designates engine design to be all inclusive, or what some may call a "middleweight" power train. Meaning that all components are designed to be in 1 set of crankcases. This particular letter and it's placement started way back in 1957 with the birth of the sportster model. Which the "X" designated an overhead valve/pushrod engine and like mentioned earlier, the primary/transmission/engine being all inclusive to 1 shared crankcase. Before this, they were known as "K" models and were flat head, side valve engines.
 

L or X- This letter is to designate type/size of front wheel.

L- designates a 16" front wheel.

X- designates either a 19" or 21" front wheel.

H/T/D/ST/R

H- designates a handle bar mounted fairing found on the Electra glides. Or in the case of a road king, a handlebar mounted windscreen.

T- designates a fixed frame mounted fairing. Such as the Road glide fairing.

D- designates the "original" dyna frame/chassis.

ST- (yes, it's more than 1 letter.) This designates a softail frame. The engineers had overlooked the fact they already had an FXS model in production, therefore they had to create something to differentiate between the "new" softail frame from it's cousin the super glide low rider. (The original FXS.)

R- designates a 3 point rubber mounted power train.

MODEL - This helps differentiate the particular model you may have. It has different effects depending on the type of Harley you have. Examples- FLHR equates to the standard road king. FLTR equates to the standard road glide. FXSTD- equates to the Softail Deuce. FXSTS equates to a springer softail. FLSTS equates to a heritage softail springer. (See the difference?) FXRS equates to a sporty feeling bike with a 19" or 21" front wheel built using the only frame at the time designed for a rubber isolated power train, the touring frame.

OUTFITTING - I write this section labeled so, because it really depends on the model you own. This can designate extra options that were designed into the model by the factory. Most times in normally consists of an "I" to differentiate the fuel injected from carbureted. To attempt to better explain, the FLHTCUI is a fuel injected, ultra classic electra glide with all available bells and whistles most people are looking for in a "bagger". The FLHRCI is a fuel injected, road king classic.

My bike is a Standard Hard Bagged Road King with fuel Injection FLHR-I
F- Big Twin engine with
L- 16" fat front tire
H- Handlebar mounted windshield
R - Road King package and
-I - Fuel Injection

My wife's bike is a Dyna Low Rider FXDL
F - Big Twin Engine, in a
X- Skinny 19" Front Wheel
D- Dyna model
L- Low Rider outfitting
 

A few other examples:

Heritage Classic FLSTC
F- Big Twin Engine with
L- Fat 16" front wheel
ST- Soft tail frame
C- Classic (Heritage outfitting)

Skinny tired Softail Custom FXSTC
F- Big Twin Engine with a
X- 19" front wheel
ST- Softail frame
C- Custom (chrome) outfitting

Ultra Classic FLHTCU
F- Big Twin engine with a
L- 16" front tire
HT- Frame Mounted Fairing
CU- "Classic Ultra" Radio, CB, Intercom, leg Fairings and chrome accenting.

Softail Night Train FXSTB
F - Big Twin engine with a
X - 19" Front Tire
ST- Softail suspension and
B - blacked out engine
 

See how much fun you can have with the Alphabet? :-)