K  KK  KR  KRM  KRTT  KH  KHK  KHR  KHRM  KHRTT  and early Sportsters

Welcome to Harley K Model, dedicated to the preservation and restoration of the 1952 to 1956 Harley-Davidson flathead unit‑construction motorcycles, With the alphabet soup of model designations, these bikes are affectionately known as the “K models”.

We also cover the early Sportster models through 1969, as these are essentially K Models with overhead valves. The Ks and early Sportsters share many components and service procedures. And many enthusiasts own both models.

The OSKRG (Old Sportster and K Model Research Group) is a group of individuals who enjoy preserving the history of these motorcycles, so others can restore them correctly, and keep them alive and running.

The K Alphabet
Regular Production
K The original, displacing 750cc, produced in 1952 and 1953
KK A hotter version of the K, produced only in 1953
KH Long stroke 888cc model, produced from 1954 through 1956
KHK A hotter version of the KH, produced from 1954 through 1956
Competition
KR Competition K - Flat Track, various years
KRM Competition K - Scrambles and Trials, various years
KRTT Competition K - Tourist Trophy racing, various years
KHR Competition KH - various years
KHRM Competition KH - Scrambles and Trials, various years
KHRTT Competition KH - Tourist Trophy racing, various years
The XL Alphabet
Regular Production
XL Overhead valves, displacing 883cc, produced in 1957, 1958, 1959
XLH High Compression, more of a luxury model, 1958-1969
XLCH High-compression, sporting magneto model - produced from 1959 to 1969
Competition
XLC/H The 1958 XLC and XLCH were real competition models
XLR Competition XL- various years
XLRTT Competition XL - Tourist Trophy racing, various years
Special Contracts
XLA U.S. Army model, 1957, and a few up into the early 1960s - 750cc
XLB Southeast Asia Police model, 1959-1967 ?
Production figures for the K and XL models can be found here
 
N.O.S. - New Old Stuff
 
2024
January
Technical - Spokes, Nipples, Hubs - UPDATED Technical : Spokes, Nipples, Hubs
Gallery: Dallin McLeod's 1952 K Gallery : 1952-1953 : Dallin's 1952 K
 
2023
July
Competition - NEW - Totally Revamped and Cell Phone Friendly Competition
Competition - NEW - Factory Brochures - thank you “Rubone” Competition : Brochures
Competition - NEW - Specifications and Instructions - thank you “Rubone” Competition : Specifications & Instructions
 
March
Technical - Nameplates and Transfers Technical : Nameplates & Transfers
Technical - Nameplates and Transfers : Patent Decals Technical : N & E: Patent Decals
The Craigslist Search has retired Desktop or Mobile
January
Gallery - A Trip To France - Pierre Martel's 1967 XLCH Gallery : 1966-1969 : Pierre's 1967 XLCH
2022
December
Technical - Battery Carriers - NEW - OSKRG Research Bulletin #16 Technical : Battery Carriers
September
Technical - Clutch - NEW - OSKRG Research Bulletin #15 Technical : Clutch
Technical - Spokes, Nipples, Hubs - NEW - OSKRG Research Bulletin #14 Technical : Spokes, Nipples, Hubs
July
Technical - Finishes - Inlet Pipes - NEW Technical : Finishes : Inlet Pipes
June
Technical - Inlet Pipes - NEW Technical : Inlet Pipes
Technical - Finishes - Carburator and Parts - updated Technical : Finishes : Carburator and Parts
April
Technical - Finishes - Gas Tank Group - updated Technical : Finishes : Gas Tank Group
Technical - Finishes - Comprehensive review process started Technical : Finishes : 1952-1956
Literature - 1963 Harley Pamphlet photos Literature : 1963
Literature - 1962 Harley ad - engine Literature : 1962
January
Minor fixes on Model 52 Generator and 1952-1956 Finishes pages Thanks, Perry!
2021
October
Technical - Transmission Gears and Shafts - VERSION 19! Technical : Transmission Gears
Gallery - Patrick Cristofaro's 1959 XLH Gallery : 1957-1959 : Patrick's 1959 XLH
July
Technical - Rear Motor Mount UPDATED Technical : Motor Mounting
June
Technical - Transmission Gears and Shafts - VERSION 18! Technical : Transmission Gears
May
Exhaust - Part 1 K-Models - UPDATED! Technical : Exhaust
April
1957 XL Another Factory Photo Literature : 1957
Gallery - More prototype photos - thanks Mostly Ironheads! Gallery : Prototypes
March
Gallery - Prototype Model K in the new Prototypes section Gallery : Prototypes
Gallery - Dave Hennessey's 1970 XLCH and 70-71 Dual Seat Gallery : 1970-1979 : 1970 XLCH
Literature - 1960 Hot Rod Magazine XLCH Road Test Literature : 1960
Literature & Technical - 1953 Standard Solo Literature : 1953
Technical: Finishes : 1953 Standard Solo
February
Gallery - Gary Myers' Beautiful 1956 KHK Gallery : 1954-1956 : 1956 KHK
 
2020
November
Technical - Transmission Gears and Shafts - UPDATED YET AGAIN! Technical : Transmission Gears
June
Technical - Wiring - 1968-1969 XLH Technical : Wiring : 1968-1969 XLH
April
Technical - Transmission Gears and Shafts - UPDATED YET AGAIN! Technical : Transmission Gears
Technical - Brakes - UPDATED Technical : Brakes
Technical - How-To Replace a Neck Casting Technical : How To
March
Technical - Wiring - Colorized Wiring Diagram Technical : Wiring : 1952-1958
Technical - How-To Replace Rear Downtubes Technical : How To
Technical - Transmission Gears and Shafts - UPDATED AGAIN! Technical : Transmission Gears
Instructions for Rear Chain Oiler Kit #63589-53 Literature : Instructions : 63589-53
February
Gallery - OSKRG-West, Davenport 2019 Gallery : OSKRG : 2019 Davenport
Technical - Safety Guards Technical : Safety Guards
Gallery - OSKRG-North, St. Paul 2018 Gallery : OSKRG : 2018 St. Paul
Literature - Directional Signals - Fiberglass Seat Literature : Instructions
January
Technical - Transmission Gears and Shafts - UPDATED Technical : Transmission Gears
Technical - Transmission Gears and Shafts Technical : Transmission Gears
 
2019
October
Technical - Frames - Updated Technical : Frames
Literature - Parts Catalogs - Fixed download problem Literature : Spare Parts Catalogs
Technical - Air Cleaner Cover - minor update Technical : Air Cleaner
April
Technical - Frames - Updated Technical : Frames
March
Technical - Generators - Model 52K - updated Technical : Generators : Model 52K
Technical - Generators - Model 52 - not used on Ks Technical : Generators : Model 52
February
Literature - Service Manuals - Added Section Dividers Literature : Service Manuals
Literature - Shop Dope - Added #403, 404, 414 Literature : Shop Dope
Technical - Stop Light Switches Technical : Stoplight Switches
Literature - Shop Dope - Added #415, 490, 491 Literature : Shop Dope
Literature - Shop Dope #455 and 458 Updated (missing pages found) Literature : Shop Dope
Literature - Service Manuals - Totally Revised Literature : Service Manuals
January
Literature - 4 More New Instructions Literature : Instructions
Literature - 19 New Shop Dope Service Bulletins Literature : Shop Dope
Literature - 4 New Instructions Literature : Instructions
 
2018
December
Domain names OSKRG.COM and OSKRG.ORG are now operational
Literature - 3 New Shop Dope Service Bulletins Literature : Shop Dope
Literature - 4 New Instructions Literature : Instructions
November
Literature - 28 New Shop Dope Service Bulletins Literature : Shop Dope
Technical - Ignition and Light Switches - UPDATED Technical : Ignition & Light Switches
Technical - Transmission Sprocket Cover - UPDATED Technical : Transmission Cover
September
Technical - Oil Tanks - All About Lunch Boxes Technical : Oil Tanks
Literature - H-D Shop Dope - K and KH Fitting Specifications
   Numbers 328, 332, 337, 346, 346A, and 347
Literature : Shop Dope
Literature - H-D Shop Dope - 1955 KH Transmission w/ Access Cover
   Number 349
Literature : Shop Dope
Literature - H-D Shop Dope - Shocks, Valves, Piston Fitting, Batteries
   Numbers 362, 366, 368, 374, and 377
Literature : Shop Dope
Literature - 1956 KH/KHK Pamphlet - The Other Side - Finally! Literature : 1956
August
Literature - 1953 News Bulletin - WOW! Literature : Factory-To-Dealer
Literature - H-D Shop Dope / Service Bulletins about Transmissions
   Numbers 345, 356, 363, 376, 471
Literature : Shop Dope
Literature - H-D Shop Dope / Service Bulletins about Carburators
   Numbers 389, 518, 547, 564, 571, 605
Literature : Shop Dope
Technical : Carbs : Model HD
Technical : Carbs : Model DC
Literature - H-D Shop Dope / Service Bulletins about Other Stuff
   Numbers 494, 546, 608
Literature : Shop Dope
Technical - DC Carb Support Brackets - XLH and XLCH Technical : Carbs : Model DC
Technical - Shock Absorbers - 1952-1955 - Update Technical : Shock Absorber : 1952-1955
July
Gallery - OSKRG-North - AMCA meet in St. Paul Gallery : OSKRG : 2018 St. Paul
Gallery - Barnsters - 1953 K - Warren & Shawn McQuiggan Gallery : Barnsters : McQuiggan
Gallery - 1957-1959 Sportsters - 1957 XL - Chad Zaemisch Gallery : 1957-1959 : Chad Zaemisch
May
Technical - Generators - minor corrections on gear teeth Technical : Generators
Literature - 1954 Cuts and Mats Literature : Cut and Mat Books : 1954
Gallery - OSKRG-East, AMCA meet in Oley PA Gallery : OSKRG : 2018 Oley
April
Technical - UPDATE - Trapdoor on 1955 KH Technical : Transmission
Gallery - Murph's Dual-DC 1959 XLCH Gallery : 1957-1959 : 1959 XLCH
Technical - Shifting Foot Levers Technical : Shifting Shaft and Foot Lever
Technical - Shop Dope - Trapdoor on 1955 KH Technical : Transmission
Technical - Late-1968 Tillotson Changes - Service Bulletin 571 Technical : Carbs : Model HD
March
Technical - Horns - update on 69145-54 Spacer Technical : Horns
February
Literature - 1961 Cuts and Mats Literature : Cut and Mat Books
Technical - Numbers updated with frame security codes Technical : Numbers
January
Technical - Starter Crank - Sportsters Technical : Starter Crank
Technical - Motor Mounting Technical : Motor Mounting
Technical - Valves and Tappets Technical : Valves and Tappets
Technical - Gas Tanks (only XLCH for now) Technical : Gas Tanks
Technical - Saddlebags - 1966 Instructions Technical : Saddlebags
Technical - Starter Crank - K and KH Technical : Starter Crank
Literature - The Elusive 1970 Parts Catalog cover Literature : Spare Parts Catalogs
 
2017
December
Technical - Rear Wheel Technical : Rear Wheel and Brake
1958 Harley Brochure Literature : 1958
1958 Ad - Jack Pine Trophy Literature : 1958
November
1964 XLH - Pohlman Photo Literature : 1964
Technical : Speedometers Updated! - now includes through 1969 Technical : Speedometers
1977 Parts Catalog Supplement Cover Literature : Spare Parts Catalogs
1974 Parts Catalog Supplement Cover Literature : Spare Parts Catalogs
Technical : Shock Absorber Technical : Shock Absorber
October
GaryM2's Gorgeous 1957 XL Gallery : 1957 XL
Lamps - added specs for 71090-59 Technical : Lamps
September
Dave Larkin's Beautiful 1955 KH Gallery : 1955 KH
Stan Diener's “New Look” for His 1953 KK Gallery : 1953 KK
Roger Meinke's Original 1956 KHK Gallery : 1956 KHK
August
1964 Option Price Changes Literature : 1964
July
1967 Sportster Brochure Literature : 1967
1966 Sportster Brochure Literature : 1966
1959 Sportster H Ad Literature : 1959
June
1953 Royalite Ad Literature : 1953
1953 Magazine P Ad Literature : 1953
1960 Dealer Ad Literature : 1960
Air Cleaner Cover - Technical Article - Update Technical : Air Cleaner
OSKRG-East - Oley 2017 Gallery : OSKRG : Oley 2017
1965 Magazine Ad - Sportsters Literature : 1965
1969 Magazine Ad - Outperformers Literature : 1969
1968 Magazine Ad - Bonneville Literature : 1968
Richard Spagnolli's 1970 XLH Gallery : 1970 XLH
Dr. Dick's Original 1960 XLCH Gallery : 1960 XLCH
Magneto Sportster's Original 1958 XLH Gallery : 1958 XLCH
1965 Harley Sportster Brochure Literature : 1965
9 to 1 Compression – 1958 Magazine P Ad Literature : 1958
Manu Nalin's Beautiful 1966 XLCH Gallery : 1966 XLCH
May
1952 Rare B&W K-model Brochure - Kerry Brethorst Literature : 1952
1968 Cycle Magazine Cover Literature : 1968
1969 Cycle Magazine Cover Literature : 1969
State-by-State - Historic and YOM License Plates Technical : How-To : License Plates
April
1957 - Motor drawing - from a dealer brochure Literature : 1957
1958 - Win a Real Live Baby Donkey Literature : 1958
1958 XLCH Literature : 1958
1959 Dealer Brochure Literature : 1959
1961 Dealer Brochure Literature : 1961
1963 Dealer All-Line Brochure (CH & H) Literature : 1963
March
Condensors - that elusive Horn Condensor Technical : Condensor
How To Make a Wedding Band Technical : How-To
February
Headlamp technical - now includes 1952-1958 Body and 1952-1958 Lamp Technical : Headlamp
Air Cleaner Cover - Technical Article Technical : Air Cleaner
January
Gallery - Update on Erik Hoopes' Barnster Gallery : Erik's 1952 K
Exhaust - Part 1 - OSKRG Technical Bulletin Technical : Exhaust
Factory Photos - Frame Assembly & Many More Technical : Frames
Headlamp - technical article (only XLCH eyebrows for now) Technical : Headlamp
Gallery - Murph's 1962 XLCH - additional photos Gallery : 1962 XLCH
 
2016
Nov & Dec
Craigslist Search - Major, Major Efficiency Improvements Craigslist
October
Brakes - Technical Article Technical : Brakes
September
OSKRG - 2016 Davenport Swap Meet Gallery : Davenport 2016
Craigslist Search - Big Improvements Craigslist
August
Finally found the December 1952 Enthusiast Literature : Enthusiast
July
Speedometers - updated illustration of rubber mounting Technical : Speedometers
More Stan Diener 1954 KH Photos Gallery : 1954 KH
More 1952, 1954, and 1957 Factory Photos
All Factory Photos now moved to the proper year sections
Technical : Colors
Literature : 1952, 1954 and 1957
1957 Spring Special Color Unearthed
Nugget Gold
Technical : Colors
Literature : Factory-To-Dealer
Transmission Covers - Jerry Raino Research Technical : Transmission Cover
June K-Model Finishes Compendium - Round 1 Finished Technical : Finishes
Finally! The 1967 Parts Catalog - now Available for download Literature : Spare Parts Catalogs
1954 KH Dairyland Insurance Poster Literature : 1954
1962 Parts Catalog Supplement - now Available for download Literature : Spare Parts Catalogs
1966 Parts Catalog Supplement - now Available for download Literature : Spare Parts Catalogs
1968 Parts Catalog Supplement - now Available for download Literature : Spare Parts Catalogs
1969 Parts Catalog Supplement - now Available for download Literature : Spare Parts Catalogs
1954 KH Brochure Literature : 1954
More 1953 KK Literature from Stan Diener Literature : 1953
Stan Diener's 1953 KK Gallery : 1953 KK
Kerry Brethorst's 1954 KHRTT Gallery : 1954 KHRTT
May Yes, they did exist!   A 1953 KK ad Literature : 1953
1959 Spring Special Color Unearthed
Hi-Fi Coral
Technical : Colors
Literature : Factory-To-Dealer
1954 Spring Special Colors Unearthed
“An ensemble of Ivory, Black and Chrome”
Technical : Colors
Literature : Factory-To-Dealer
Bill Coleman's Original 1953 KK Gallery : 1953 KK
Technical: Circuit Breakers (updated) Technical : Circuit Breakers
1959 Dealer Package (from Dr. Dick) Literature
Stan Diener's 1954 KH Gallery : 1954 KH
K Finishes - 70% done - 42 down, 18 to go Technical : Finishes : 1952-1956
April OSKRG-East - at Oley 2016 Gallery : Oley 2016
How To - Parkerize Parts Technical : How To : Parkerize
How To - Get A Title Technical : How To : Titles
March Roger Meinke's Factory-to-Dealer Docs Literature
Roger Meinke's 1959 XLCH Magazine Ads Literature
February Wheels and Tires Technical : Wheels and Tires
Finishes - Phase II Technical : Finishes
1952 K Factory Advertisement Literature
Revised: Shipping Date Guess-O-Meter Tech : Numbers : Guess-O-Meter
January Spare Parts Catalogs On-Line - 1961 Supplement Literature : Spare Parts Catalogs
Wiring Diagrams Technical : Wiring
Crankcase Tech Article Technical : Cranckcases (PDF)
Brian Kane's 1967 XLCH Gallery : 1967 XLCH
Spare Parts Catalogs On-Line - 1964 Supplement Literature : Spare Parts Catalogs
Spare Parts Catalogs On-Line - 1965 Full Catalog Literature : Spare Parts Catalogs
Spare Parts Catalogs On-Line - 1960 Supplement Literature : Spare Parts Catalogs
 
2015
December Shipping Date Guess-O-Meter Tech : Numbers : Guess-O-Meter
Anonymous's 1954 KHK - The Last 1954 Made? Gallery : 1954 KHK
KHs Escort Haile Selassie in 1954 Literature : Eindhoven Police
Two More Enthusiasts Found Literature : The Enthusiast
Spare Parts Catalogs On-Line - 1953 Literature : Spare Parts Catalogs
November Three More ex-Mike Quinn KH-es Gallery
ex-Mike Quinn 1953 KRTT Gallery : 1953 KRTT
ex-Mike Quinn 1953 KRM Gallery : 1953 KRM
ex-Mike Quinn 1952 K Gallery : 1952 K
1953 Harley Brochure Literature : 1953 Harley Brochure
Oil Tanks Technical : Oil Tanks
More Paint Colors Found! Technical : Colors
Magneto Sportster's 1959 XLCH Gallery : 1959 XLCH
Magneto Sportster's 1966 XLCH Gallery : 1966 XLCH
Spare Parts Catalogs On-Line - 1963 Literature : Spare Parts Catalogs
October 1953 - Four More Colors Found Technical : Colors
Rob White's 1968 XLH Gallery : 1968 XLH
Spare Parts Catalogs On-Line - 1954, 1955, 1956, 1957, 1959 Literature : Spare Parts Catalogs
September The OSKRG Luncheon at Davenport 2015 Gallery : OSKRG
John Hewson's 1953 K Gallery : 1953 K
1953 KRM Barnster Gallery : 1953 KRM
Dennis Schoenfeldt's 1961 KR Gallery : 1961 KR
August Literature - 1968 Sportster Ad Literature
July Literature - 1959 XLCH - Hot Rod magazine Literature
Gallery - Mike Walker's 1956 KH Survivor/Barnster Gallery : 1956 KH
Literature - 1956 KHK, 1952 Popular Mechanics Literature
Technical - Battery and Fittings Technical : Battery
Gallery - Doug Feinsod's 1952 K Barnster Gallery : 1952 K
Gallery - Dave Swanson's 1956 KHK Gallery : 1956 KHK
Literature - Pohlman Prints Literature
June Gallery - Dave Carlton's 1968 XLCH Gallery : 1968 XLCH
The Production Figures Return! History : Production Figures
Added 1975 Parts Cover, updated 1972 Parts Cover Literature : Parts Catalogs
May Technical - Regulators - Added 2 Delco-Remy Docs and 2 Shop Dopes Technical : Regulators
February Literature - Parts Catalogs Updated Literature : Parts Catalogs
Technical - Frames Updated Technical Frames
Technical - Carburators - Updated Technical : Carbs
Technical - Added Colors Section Technical : Colors
January Literature - Enthusiast - added 5 covers Literature: Enthusiast
Gallery - Dave Carlton's 1961 XLCH Gallery: 1961 XLCH
Technical - added wiring diagrams to several models Technical : Generators
Gallery - Dave Carlton's 1967 XLCH Gallery: 1967 XLCH
 
2014
November Technical - Updated DC Carburator Document Technical: Carbs
Gallery - More photos of Michael Broad's 1955 KH Gallery
Gallery - More photos of Model-H's 1958 XLH Gallery
Literature - Mike Broad's great 1955 KH Brochure Literature
Gallery - added Hans Postema's 1956 KH Gallery
Gallery - added Don Chasteen's Black 1957 XL (partial) Gallery
Gallery - added Don Chasteen's Blue 1957 XL (partial) Gallery
Technical - added Magnetos Technical: Magnetos
Technical - added Horns Technical: Horns
October Literature - added 1957 Cuts and Mats Book Literature
Literature - added Parts Cats, Service Mans, Enthusiasts Literature
September Technical - Wet Clutch Assembly Technical: Clutch
Gallery - OSKRG Luncheon at Davenport Gallery
Gallery - Gene Payne's 1961 XLR and 1970 XLR-900 Gallery
Gallery - Jack Raino's 1957 XL, Tom Auerback's 1969 XLCH Gallery
Gallery - Dave Carlton's 1966 XLCH and 1969 XLCH Gallery
August Gallery - Murph's 1953 K and 1962 XLCH Gallery
Technical: Numbers - K/KH - The Letter D Technical: Numbers
Gallery: Doc's 1959 XLCH Photos Gallery
July Gallery: 1954 KH Barnster Photos Gallery
Technical: Serial and Other Numbers Technical: Numbers
June Gallery: Michael Broad's 1955 KH Gallery
Gallery: Barnster® Photos Gallery
Gallery: Tom White's KRM Gallery
Technical: Regulator Info Technical: Regulators
May Gallery: Glenn Bator's Beautiful 1952 K Gallery
Story: Erik Hoopes and Joe Leonard Go Couch-Racing Competition
Photos of Ks and early XLs seen at the Oley Swap Meet Gallery
April Updated Frame Chart from Jerry Raino Technical
 
March 15   The Domain Name, harleyKmodel.com was registered