Easy Fixins

Easy Fixins

Big Twin Harleys


Listed below are the 6 major H-D engine styles and some associated information.

Flathead 1929 – 1935

Knucklehead 1936 – 1947 In the world of Harley-Davidson there are two different schools of thought. One think’s that the pre-teen H.-D.’s are the most collectable. The other feels that the Knuckleheads are the machines that make Harley-Davidson possible today. And if Knuckles are your love, then you realize that the ‘36-61″ is the great-grandfather of today’s Evolution.

The first Knuckleheads appeared in dealer show rooms in about April of 1936, Designwork had started in August 1931 and though initially proposed to be a 1933 model to replace the beleaguered VL, production and design problems increased development time. The 61″ OHV engine was installed in a new chassis, that had been designed in 1931 for a 65”” sidevalve. It was a double looped frame, tubular chrome-molybdenum forks with welded gas tanks, a seperate oil tankand an integrated tank top instrument panel. Although not exactly as the prototype all of these features were on the Knuckleheads.The 65″ sidevalve had been dropped after the poor acceptance of the first VL. An engineering report, signed by William S. Harley on November 23, 1934, showed the 61″ OHV as a 1935 production model. But problems with oiling and excessive sprocket, chain and brake wear caused the founding fathers to consider scrapping the OHV project as late as April 1935. However by June of ‘35 they had agreed to go ahead with final development of the 61″ OHV. At the National Dealers Convention in November of ‘35 the 61″ OHV was shown for the first time. Although dealers had heard rumors of its development for years, this was the first time the factory had acknowledged it. Still not giving a date for delivery the factory showed a line drawing of the 61″ in its December 2, 1935 dealers 1936 new model announcement followed by this statement.


For several years rumors, have been current all over the country, about a new Twin that Harley-Davidson was developing and would have on the market at any day. The most incredulous and many times positively amusing fabrications have been spread about this model. True our engineering staff has been working for a long time on a model of new and original design and their efforts finally reached a stage were such a motorcycle, a 61 cubic inch overhead, was shown to the dealers in attendance at the National Dealers Convention. However, production on this model will necessarily be extremely limited and we are therefore in no position to make a public announcement at this time….Under no circumstances should this model be ordered as a demonstrator!

In December 1935 the first ten or so preproduction models were assembled.These were used for testing purposes and were later disassembled.. Factory photographs of two 1935 models show engine numbers 35EL1002 and 35EL1003. Note that these are full production serial numbers and not prototype numbers. As far as we know not a single 1935 EL exists today.

The ‘36 OHV model year did better than anticipated. Original plans called for 1,600 units to be built. Between March and August business was so good that the factory could not fill all of their orders. But as late as September 30, 1936 Walter Davidson announced in his presidents report to the stockholders, that 1,836 had been sold. But no reference was given about how many were made. However they did agree to hold back deliveries of all 1937models until October to ensure sales of all remaining other 1936 models.

The October 19,1936 dealers 1937 announcement news bulletin states; For years our engineers had a vision of a new motorcycle – one that would eliminate many of the problems inherent with the conventional design of the day. They visioned a motorcycle that would render still greater service, still longer life, and still greater operating economy. With this goal, they began work planning and designing a new motorcycle that would retain all the best of the past and incorporate all those new principles that would producea motorcycle unparalleled in performance and efficiency. Rumors were afloat for years about this new motorcycle that was being developed by Harley-Davidson. At our National Dealer Convention in Milwaukee late last fall, dealers were given a preview of a new Harley-Davidson, a 61″ OHV, replete with revolutionary and breath-taking advancements. Frankly, dealers and riders were astounded. In decades, no new model created such a sensation!

With years of development behind the new model, and with 70,000 hours of testing, we knew we were bringing out a new motorcycle that would eclipse everything ever produced before. But with characteristic Harley-Davidson thoroughness, we wanted to get owner reaction, owner experience, and see how this new model performed in the hands of the public before we advertised it extensively and before we incorporated these new principles into the other models of our line.

Harley-Davidson dealers know how the 61″ OHV was introduced. Without advertising fanfare and publicity, the new model was gradually introduced here and there, principally to older riders who immediately sensed that here was a motorcycle that embodied the dreams they had hoped would some day come true. And what enthusiasm the 61″ OHV is causing! Never in all our long history have so many words and letters of praise been showered upon a new model. Demand for the new machine grew by leaps and bounds. Nearly 2,000 of these new 61″ OHV Harley-Davidsons are piling up miles of the most satisfactory service ever rendered by a motorcycle. We were happy – ourlong, arduous efforts were not in vain.

No one knows for sure just how many ‘36 OHV’s were built. The factory’s service department has this information but will not divulge it. However according to serial numbers registered by members of the ‘36 EL Registry the highest known serial number is 36EL2945. Serial numbers started at 1001 so this puts 2945 as being the 1945th machine built. How many are left? The registry has over a hundred and thirty seven surviving serial numbers registered, but of these only about twenty are original, complete machines.This is probably the only post-teen model with so few surviving. So if you are interested in owning the great-grandfather of the Evolution, be prepared to step up. Good luck.

The ‘36 EL Registry is a group of owners and lovers of the ‘36EL. Headed by Gerry Lyons. He publishes a bimonthly newsletter with tech. articles, free want ads and general articles involving the ‘36 EL’s. Their address is 1240S. Vineland Road C-3, Wintergarden, FL 34787 Phone (407) 654-0230.

Panhead 1948 – 1965

Shovelhead 1966 – 1984

Evolution 1984 – Present

Number of Cylinders: 2
Type: 4-Cycle, 45 Degree V-Type
Transmission Type: Constant mesh, foot shift
Speeds: 5 forward
Bore x Stroke (in): 3.498 x 4.250
Displacement (cu in/CC): 80/1340
Compression Ratio: 8.5:1
Fuel System: Carburetor or Electronic Sequential Port Fuel Injection (ESPFI)
Oil Capacity (U.S. qts): 3 or 4
Primary Drive: Double-row chain
Gear Ratios: Dyna Softail Touring 1st: 10.110 9.388 10.110 2nd: 6.958 6.461 6.958 3rd: 4.953 4.599 4.953 4th: 3.862 3.586 3.862 5th: 3.150 2.925 3.150 Torque, Dyna/Softail: 79.0/76.0 ft./lbs.@ 3500 RPM Torque, Touring w/carb: 77.0 ft./lbs. @ 4000 RPM Torque, Touring w/ESPFI: 83.0 ft./lbs.@ 3500 RPM Miles Per Gallon Dyna/Softail: 55 hwy./43 city Miles Per Gallon Touring(w/carb): 50 hwy./40 city Miles Per Gallon Touring(w/ESPFI):52 hwy./42 city

Twincam 88ci.: 1998 to Present


Harley Davidson Alphabet
(from American Rider, January-February 1995)
by Clement Salvadori

A great many people over the years have become suitably confused by Harley-Davidson’s model designations. And rightfully so. The alpha-designations merely exist, the letters seemingly drawn out of thin air.

Today, even though we have only two basic engine designs to deal with, the Sportster X and big twin F, the number of letters for one model would do credit to a bowl of soup. For example, the 1995 model line included the FLHTCI and the FXSTSB – mouthfulls both.

Let us analyze these. First, the FLHTCI bagger. The F stands for the medium compression 74-inch OHV engine introduced in 1941; the L stood for the slightly more powerful “Special Sport Solo” version. The H was tacked on in 1955, indicating the “Super Sport Solo.” In 1978 the 80-inch engine was introduced as an option, and by 1981 the F model designation meant an 80-incher. The T was added in 1983 to indicate that this was a touring machine with bags and batwing fairing, and the C also came in that year to show that this model had “classic” looks and a higher price tag. The I is the first use of that letter, and is alphabetical proof that this model is fuel-injected rather than carbureted.

Got all that?

Now the FXSTSB. The F has been demonstrated. The X shows that this big twin had the lighter, Sportster-type front end inaugurated in 1971. The ST (in this case those letters have to stand together) stands for the Softail chassis design, introduced in 1984. The second S is the Springer front end, intro-ed in 1988. The B is for the new 1995 model, the Bad Boy.

Confused? And rightfully so. While all these letters might not make much sense to the average Harley enthusiast, they help a lot in the parts department – especially when prefaced by a year, such as an 1984 FXRT.

Often the first alpha-designation a Harley enthusiast interested in Harley history hears is about someone’s JD model, indicating the 74-inch V-twin introduced in 1921, but the lettering goes back long before that.

Up to 1908, there was only one Harley model per year, a battery-fired single cylinder, so any further designation than the year was superfluous: i.e., an 1907 Harley. But in 1909, the factory offered four singles, with either 26- or 28-inch wheels (wheels were measured from the outer edge of the tire back then), and either battery or magneto ignition. These were referred to as the Model 5 (fifth year of production, which, for Harley-Davidson purposes, began in 1904) with battery and 28s, the Model 5-A with mag and 28s, 5-B with battery and 26s and 5-C, mag/26. The abortive twin was called the 5-D.

In 1910, the single-cylinder racer was called the 6-E. In 1912, things got real complicated with both chain and belt drive being offered, and a clutching mechanism designated by an X; all wheels were the 28-inch variety. The basic single was the Model 8, the mag-fired twin with “freewheel control” and chain drive was called the Model X-8-E.

In 1914, we see the first use of the F letter, a 61-inch magneto twin with two-speed gearbox. In 1915, the J model appeared, the twin with three-speed transmission and battery ignition. That was also the year of the first K model, a racing twin.

In 1916, the year designation was changed from year of production to calendar year, so it was not 12-F, but 16-F. Eight models were available that year: the F, J, E, R and T twins, and C, B and S singles. Already Harley was complicating things, as the E of 1910 was a racing single, while the E of 1916 was a one-speed twin.

The heck with this; let us start with the alphabet and go right through to see how many letters have been used, and how many times. When you see a /, that means the letter(s) was secondary (FL), tertiary (FLH), etc. To try to keep this under control, I will start with the models that were in the 1920 line, and ignore what went on before that date.

A (1926): SV/OHV 21-inch single (magneto ignition)
A (1960): TS (two stroke) 165CC Topper scooter
B (1926): SV/OHV 21-inch single
B (1955): TS 165CC single
/B Belt-drive Sturgis model (ex. 1982 FXB)
C (1920): i.o.e. 35-inch single, special order
C (1930): SV/OHV 30.5-inch single
/C Custom, Classic or Caf
/CH Magneto Sportster (ex. 1958 XLCH)
D (1929): SV 45-inch twin
/D 74-inch engine (ex. 1921 JD)
/D Extra power (ex. 1930 DLD)
/D Dyna Glide frame (ex. 1991 FXDB)
/DG Disc Glide (ex. 1983 FXDG)
E (1936): OHV 61-inch twin
/E Electric starting (ex. 1964 GE, 1974 FXE)
/E Police engine (ex. 1953 FLE)
F (1920): i.o.e. 61-inch magneto ignition (dating from 1914)
F (1941): OHV 74-inch twin
/F Battery ignition flat twin (ex. 1921 WF)
/F Footshift (ex. 1952 FLF)
G (1933): SV 45-inch Servi-Car
/H Larger engine (ex. 1936 80-inch VHL, 1955 55-inch KH)
/H More powerful engine (ex. 1955 FLH)
I Fuel injection (ex. 1995 FLHTCI)
J (1920): i.o.e. 61-inch twin (dating from 1915)
/J: Magneto ignition flat twin (ex. 1921 WJ)
/K: More powerful K model (ex. 1955 K11K)
L (1920): Single-passenger sidecar (dating from 1915)
/L: Higher compression engine (ex. 1936 EL)
M (1920): Commerical sidecar (dating from 1915)
M (1965): TS 50CC single, Aermacchi
/N: Newspaper delivery sidecar (ex. 1929 MN)
/N: Nostalgia (ex. 1993 FLSTN)
/O: Open-body commercial sidecar (ex. 1926 MO)
/P: Police model
Q (1920): Two-passenger sidecar chassis (dating from 1918)
R (1932): SV 45-inch twin
/R: Rubber-mount FX model (ex. 1982 FXR Super Glide)
/R: Pseudo-racing model (ex. 1983 XR-1000)
/R: Racing model (ex. 1952 KR)
S (1926): OHV 21-inch, for racing purposes
S (1948): TS 125 single
/S: Sport (ex. 1978 FXS and XLS)
/S: Sidecar use (ex. 1936 ES)
T (1921): Twin-cylinder racer
/T: TS 165 single (ex. 1953 ST)
/T: Touring (ex. 1977 XLT, 1980)
U (1937): SV 74-inch twin
V (1930): SV 74-inch twin
V (1994): DOHC 61-inch twin, for Superbike racing
W (1920): SV 36-inch flat twin (dating from 1919)
W (1937): SV 45-inch twin
/WG: Wide Glide (ex. 1980 FXWG)
X (1957): OHV 55-inch twin (usually used with L; i.e. XL)
Y: Only letter never used
Z (1973): TS 90CC single, Aermacchi

All the learned readers can now berate me for my inaccuracies and omissions, such as racing models, sidecars, package trucks, etc.

I also left out most of the Aermacchi model designations, or this would have been far more complicated than necessary. Nor did I include all alphabets in all models; there are just too many.


You Asked the Colonel About Harley and Davidson

Lanett W. Draper (lwdraper@aol.com)wrote to inquire:
“Could you please tell me where the founders Harley and Davison were from, as well as from what counties their parents were from?”

I am assuming you meant to inquire what countries, not counties.

William S. Harley (1880-1943) was the son of emigre parents from England and grew up in Milwaukee, Wisconsin with boyhood friend Arthur Davidson (1881-1950). The two men worked at the same Milwaukee manufacturing plant when, in 1901, they conspired to build a motorcycle. William was a draftsman and Arthur was a pattern maker. Their first effort flopped when they learned that a regular bicycle frame was not strong enough and the engine they used was not big enough.

In 1902, the first Harley-Davidson production engine was built. Assistance on the carburetor design came from Ole Evinrude, who soon afterwards became a pioneer in outboard motors.

At this point, Arthur’s two older brothers entered the picture. They had been employed by the railroads. Walter Davidson (18__-1942) was a machinist and William A. Davidson (1871-1937) was a toolmaker. The Davidson brothers were sons of a carpenter from Scotland, and it was their father who built the first Harley-Davidson factory. Constructed in the Davidson’s back yard, the “factory” was a 10 x 15 foot shed with the words, Harley-Davidson Motor Co.” painted on its door.

In 1903, the same year that Wilber and Orville Wright took their machine to the air, the four founders of Harley-Davidson Motor Company built three machines; and three more were completed the following year.

By 1904, the company was also producing carburetors, marine engines and propellors. William Harley was quick to realize that the growing business required expertise beyond that which any of the founders had, so he enrolled in engineering at the University of Wisconsin.

In 1905, the first outside employee was hired and in 1906 production increased to 50 motorcycles, called “Silent Gray Fellows,” selling at $200 each.

In 1907 production soared to 152 motorcycles and the company incorporated. Walter Davidson was named president and shares of stock were distributed among family members and the company’s 17 employees. Stock sales and financing from Uncle James (known as the “honey uncle” because he was a beekeeper) Davidson provided the funding for Factory Number Two, a 2300-square-foot building. When the building had been framed, management got word that it was too close to the adjacent railroad right-of-way. The crew rounded up a few volunteers who simply picked up the building and moved it back a few feet.

Arthur Davidson became sales manager of the new corporation; William A. Davidson was factory manager and William Harley was Chief Engineer.

Another item of interest concerning the founding four fathers is that Walter was considered the most aggressive, tenacious and best rider. Although the company did not participate in racing, it was active in endurance contests and Walter completed his – and the company’s – first endurance trial with a perfect score. A week later, Walter rode to victory in an economy run, posting the top mark of 188 miles per gallon.

William A. Davidson was the first of the four to die, in 1937. Walter died in 1942 and William H. Davidson (son of William A.) assumed the reins as company president from 1942-71.

` William Harley died in 1943, leaving his boyhood friend Arthur as the sole survivor of the original founders. Arthur and his wife were killed in an auto accident in 1950, when Arthur was 69 years old.

Today, the best-known descendant of the founding four is Willie G.Davidson, known to H-D afficionados as “Willie G.” He joined the company in 1963 as Director of Styling and remains active in the industry. Willie G and his wife, Nancy, are regulars at major gatherings and can most often be found at the center of huge groups of autograph-seekers.