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Technical: Horns
John Andrew, Scott Lange, Dave Hennessey

There were three styles of horn used on 1952 through 1969 K-models and Sportsters: Trumpet, 1959-1964 XLCH, and 1965 and Later. Within each style, there are some subtle differences, and some not-so-subtle differences. Complicating matters are differences in later production offered as spare parts.

Trumpet Horns

The trumpet horn was used on 1952 to 1956 K and KH, and 1957 to 1964 XL and XLH. The K's horn was so pretty that Harley decided to adapt them for use on the Big Twins from 1954 through at least 1964. Some of the Big Twin adaptations slowly found their way onto the unit-construction twins.

Power Packs
There were three "power packs" used on the unit-construction twins.
The 69015-52 power pack, which was used on the 1952-1956 K and KH. Salient features are the triangular ribs, and the “yoke” style mount, which fit over the top motor mount.
Note: This example has the 1955-56 spacer 69145-54 shown below.
The 69014-54 power pack, as used on the 1954-1957 Big Twin and on the 1957 XL. The horn front no longer has the triangular ribs, but retains the steel "yoke" mount. The body is also thicker than the -52, requiring a thicker cover.

The 69014-54 power pack, as used on the 1958-1964 Big Twin, and the 1958-1964 XL & XLH. Although the part number did not change, the steel mount was replaced with a reinforced rubber one. The rubber mount is shown in the 1958 Parts Catalog Supplement.

This was probably a running change in late 1957 simultaneous with a change in the choke lever mechanism from version 2 to version 3. See, OSKRG DC Carburator document, page 17.

Power Pack Covers
There were two power pack covers used on the unit-construction twins. The thick -54 Cover was developed for the Big Twin power pack, but found its way onto the KH and XL as Harley consolidated their parts inventory.
The 69140-52 (Thin) cover was used on the 1952 - 1954 K and KH. The salient feature is that it is 1-3/8 in thick. The 69140-54 (Thick) cover was used on the 1955 - 1964 KH, XL, XLH. It is 1-3/4 in thick.

Harley replaced the thin -52 cover with the thick -54 cover in 1955 (maybe late 1954). To adapt the -54 cover to the early power-pack, a 69145-54 spacer was required. The fitting was sold separately, and a 69140-52A Horn Cover and Fittings was also available. This assembly was the -54 cover, and the fittings (plural) were just the 69145-54 Horn Cover Spacer (singular). This spacer, shown at right, takes up the extra thickness of the later cover when used with the -52 power pack.

The photo of the power-pack with spacer attached shows what appears to be a large washer. This washer is not shown in the parts books. Whether the spacer includes the washer is unclear.

Trumpets

Trumpets follow the 1-2-3 rule: one bend fits K/KH, two bends fit Sportster, three bends fit Big Twin.

There were two trumpets used on the K and KH.

Both trumpets have the same part number. The difference is the length of the thread where it goes into the power pack, and the width of the nut. It is likely that the Big Twin trumpet had the longer thread, and Harley later redesigned the K trumpet to match. The 1956 Spare Parts Catalog shows the 69017-52A Horn Trumpet Nut. It is possible this change ocurred in 1955. Also, look closely at the crimped edge at the trumpet opening - this is an original.
The K and early KH trumpet had a short thread, and uses the thin 69017-52 Horn Trumpet Nut. The later KH and XL/XLH trumpet has a longer thread, and uses the thicker 69017-52A Horn Trumpet Nut.
Later production - Later production of these trumpets, both as originals, and as spare parts, showed some small differences. Most notable is the lip at the edge of the trumpet opening. On the originals, the lip was bent over at 90-degrees. Later production had the lip completely rolled over. The ridge on the early units ended at the connection, where on the later units, it extended about 1/4 to 3/8 inch past the connection. Minor differences in assembly and spot-welding can also be noticed.

There were two trumpets used on the XL & XLH.

Both trumpets have the same part number. The difference is the shape of the mounting tab. It is believed that the early horn was used only in early 1957.
Here's a generic 1957-1964 XL/XLH horn. Scott Lange compares a later model horn (extra-long gusset on the mounting tab), left, to an early 1957 one, at right.
1959 - 1964 XLCH Horns

The competition-minded XLCH used a compact horn, mounted on the left side of the motorcycle. Note that the 1958 XLCH did not have any horn at all.

From 1959 through early 1962, the XLCH used the venerable Delco 6v horn that had been used on Harleys since the 1930s. We believe that this horn was used at least through serial number 2490 (production #490 out of 1,998 that year), but how far beyond that is unknown.

This horn had come with a variety of brackets to suit the big twins, small twins and Servi-Cars through the decades. The -47, -47A, and -47B incarnations, with the one-sided mounting bracket, appeared on the 1948 Model 125 single, and continued on the Model 165 through 1959. The -47B version, marked “Type M”, has four leaves on the mounting bracket, was used on the 1957-1959 Model 165 the 1958-1961 Servi Car, and was also used on the XLCH from 1959 through early 1962. These horns can be found on the Hummer-series bikes, but be sure to count the leaves on the mounting bracket - the four-leafed -47B version started in 1957, as announced in the September 1956 Enthusiast.

See Harley Hummer Club: Restore: Horns for details and more photos.

The 69002-47B “Wings” horn was used on 1959 - early-1962 XLCH, as well as 1957-1959 Model 165, and 1958-1961 Servi Car. Look for “Type M”, and count the four leaves on the mounting bracket!  Earlier Hummer-series versions had only two leaves, and were marked “Delco Remy - 16”.

Suddenly, in early-1962, the venerable Harley “Wings” horn was gone, replaced by a different Delco unit, the “Type S”, commonly called the "Swiss Cheese" horn. This horn was also used on 1962 through 1963 Servi Car.  It was also listed as a replacement for the Model 125/165 singles - under the part number 69002-47C, although it was never used in production on those models. Regardless of what you call it, it is a tough horn to find.

It's easy to see where this horn got its nickname. The studs look like a cover would mount on it in some other automotive-type application, but what that application was is unknown. The 69002-47C horn was offered as a replacement part for the Model 165 single. It is the same horn as the 69002-62. (See: Harley Hummer Club) Same horn, two different part numbers.

Replacements - Apparently, in late 1964, Harley started offering a “Horn Conversion Kit – XLCH” to use an Italian-made C.E.V. horn. Since Harley owned 50% of Aermacchi at the time, perhaps they found it less expensive to source 6v horns from Italy.

1965 and Later Horns

The 12-volt craze hit the Sportster world in 1965, and brought with the it “Cowbell” horn, for both the XLH and XLCH models. This is an automotive-style horn reminiscent of what you'd find in a 1965 Buick. It was used up until 1975, with several changes to the mounting bracket over the years. The 69138-65 Horn Cover also had some minor changes over the years.

Seeing Double? - Around 1970, Harley started offering a 69003-70 “Twin Horn Kit”. We've never seen one, but we think it was a special mounting bar with a low-note (F-note) and a high note (A-note) horn and matching covers. Most GM cars of the 1960s and 1970s used two different Delco horns mounted on different sides in front of the radiator. The F-note and A-note horns were mirror images of each other.