What is the most important thing to decide before starting a custom motorcycle build?

Decide how the bike will be used first. Whether it’s for city riding, cross-country touring, camping, or track riding, each purpose points toward different part choices. Once the bike’s intended use is clear, selecting the right components becomes much easier. The How to Build a Bobber guide is a solid starting point for the full build process.

How do I make my motorcycle faster?

Start with a free-flowing air filter and an exhaust system that is properly tuned for your carburetor or fuel injection setup. For greater performance gains, consider increasing engine displacement with a big bore kit and improving airflow with custom camshafts or cylinder head work. Since each modification builds on the previous one, tuning after every upgrade is important.

What should I change first to make my motorcycle more comfortable?

Focus on three key areas: the seat, footpeg position, and handlebar setup. Handlebar rise and pullback typically have the greatest impact on comfort, handling, and riding posture. Investing in a quality seat can also significantly improve comfort on long rides.

Are custom Harley parts compatible with all Harley-Davidson models?

No. Fitment depends on the specific part and model year. Harley-Davidson aftermarket parts are often designed for particular platforms such as Big Twin, Sportster, or Softail models, and compatibility can vary by year range. Always review the fitment information on the product listing before ordering, and contact the supplier if compatibility is unclear.

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BEST SELLING BRANDS

TOP Custom Motorcycle Parts

Colony #9932-8 Intake Manifold to Cylinder Head Allen Kit 1995-Up Harley-Davidson Big Twins/XL
2 reviews $6.33

Colony #3804-6 Chain Guard Stud Mounting Kit 1926-1939 Harley-Davidson Singles 1929-1935 45 Twins
$12.65

Colony #3472-3 Oversized Transmission Bottom Stud Kit 1926-1932 Harley-Davidson Singles 1926-Up 45's
$25.30

Colony #2699-1 Linkert Carburetor High Speed Needle OEM #27297-27 - CAD Plated
$25.30

Colony #2713-42 Instrument Panel Base Restoration Kit 1947-1957 Harley-Davidson Big Twins
$25.30

Colony #2696-5 Linkert Low Speed Needle Valve 3-1/2 inch 1948-1965 Harley-Davidson Type 2 Heads
$25.30

British Standard Engine and Transmission Lock Tab Set - 1963 - 1972 Triumph 650 with 4 Speed Gearbox
14 reviews $25.25

Cycle Standard Neutral Indicator Light for Harley-Davidson OEM #68024-92A
7 reviews $12.53

Colony Axle / Wheel Spacer 1-1/4 x 3/4 x .438 Harley-Davidson #AS-002 — Colony #AS-002 Axle/Wheel Spacer 1-1/4 x 3/4 x .438
$8.35

Colony #2767-10 Front Safety Guard Mounting Kit 1932-1973 Harley-Davidson 45s - Parkerized
2 reviews $25.05

Colony #9722-18 Footboard Hinge Bolt Buddy Footrest Bolt Kit 1941-1964 Harley-Davidson All Models - Parkerized
$25.00

Colony #3630-3 Rear Brake Rod Spring Pull 1936-1937 Harley-Davidson Big Twins 1934-1936 WL 1934-1938 Servi-Car - Parkerized
$25.00

Colony #3068-30 Primary Cover Screw Kit 1956-1964 Harley-Davidson Big Twins - CAD Plated
1 review $25.00

Colony #8156-30 Primary Cover Screw Kit 1936-1964 Harley-Davidson Big Twins - CAD Plated
$25.00

LCFabrications Yamaha xs650 Brass Carburetor Brace
7 reviews $25.00

LCFabrications Yamaha xs650 Tach Drive Plug / Eliminator - Aluminum
14 reviews $25.00

Colony #8860-8 Cylinder Base Stud Spacer 1978-1984 Harley-Davidson Shovelhead OEM #16836-78 - Chrome Plated
1 review $24.98

Cycle Standard Throttle Cable OEM #56421-06 Harley Dyna 2006-2017 - Blacked Out
1 review $24.96 $35.66

Colony #9601-10 Inner Primary Cover Rear Bolt Kit 1936-1964 Harley-Davidson Big Twin - Parkerized
3 reviews $12.45

Cycle Standard Lucas 5K Resisitor Type Spark Plug Cap
1 review $12.44

EMGO Universal Folding Foot Pegs
1 review $23.69

British Standard 1/4 inch BSP Petcock Fuel Valve Reserve For Triumph 650 750 Norton 750 850
3 reviews $24.78

Colony #3557-1 Sprocket Shaft Bearing Retainer Seal 1955-1968 Harley-Davidson 74's
$8.25

Colony #3350-7 Clutch Release Stud Bushings 1936-1984 Harley-Davidson Big Twins - Parkerized
1 review $24.75

Colony #8736-24 Valve Cover Screws 1954-1965 Harley-Davidson Panhead With Steel D-Rings - Chrome Plated
$24.71

Colony #8493-2 Oil Tank Drain Plug 1981-Up Harley-Davidson Big Twin - Chrome Plated
1 review $12.34

James Gaskets Primary Cover Gasket 1952-1969 Harley-Davidson XL
$12.32

Lowbrow Customs Solo Seat Springs - Hairpin Style -3 inch Black
18 reviews $24.56

#3104-14-P Transmission Side Cover Chrome Polished Allen Kit Harley Touring 2017-up — Colony #3104-14-P Transmission Side Cover Polished Allen Kit 2017-Up Harley-Davidson Touring - Chrome Plated
$24.48

Cycle Standard 41mm Triple Lip Fork Seal Rebuild Kit - 1949-1977 Harley-Davidson FL
$24.45

Colony #2084-2 Seat Post Bushings 1958-1984 Harley-Davidson Big Twins OEM #47094-58
1 review $24.37

Colony #8742-14 Oil Pump Mounting Kit 1967-1977 Harley-Davidson Big Twins - Chrome Plated
$24.37

EMGO Clutch Cable Triumph 750 Twins T140 TR7 OEM #60-3925
11 reviews $24.29

No School Choppers 1928 - 1932 Ford Duolamp Tail Light Replacement Glass Lens - Red
2 reviews $24.20

Colony #3228-1 Upper Fork Bearing Adjustment Nut 1949-1984 Harley-Davidson 4-speed Big Twins 1993-2005 FXDWG 1984-2006 Softail - Zinc Plated
2 reviews $12.10

Colony #2990-2 Generator Screw Kit CAD Special 5/16 inch case holes Harley Big Twins 36-57 — Colony #2990-2 Special Generator Screw Kit 5/16 inch Case Holes 1936-1957 Harley-Davidson Big Twins - CAD Plated
2 reviews $12.10

Colony #2799-1 Upper Fork Bearing Adjusting Nut 1948-1984 Harley-Davidson FL 1984-2009 FXST 1991-2005 FXDWG - CAD Plated
5 reviews $12.10

Colony #2558-1 Clutch Adjusting Hole Filler Cap 1986-1990 Harley-Davidson Sportster
2 reviews $24.20

Colony #2066-13 Primary Cover Phillips Screw Kit 1977-1980 Harley-Davidson Sportster - CAD Plated
$24.20

Colony #2064-14 Primary Cover Phillips Screw Kit 1971-1976 Harley-Davidson Sportster - CAD Plated
1 review $24.20

Colony #9910-4 Fork Slider Drain Screws 1973-Up Harley-Davidson XL/FXR - Chrome Plated
5 reviews $4.84

Colony #8149-12 Timing Cover Screw Kit 1936-1969 Harley-Davidson Big Twins - Chrome Plated
1 review $24.20

Colony #3049-7 Chain Oiler Adjusting Screw Kit 1932-E1950 Harley-Davidson Twins 1932-1957 45's - Parkerized
$12.09

Cycle Standard Throttle Cable OEM #56633-06 Harley Dyna 2006-2017 +4 inch Extended
$24.10

Colony #3674-10 Sprocket Bolts Knurled 1979-1990 Harley-Davidson XL 1993-1998 Big Twins - Chrome Plated
$24.01

James Gaskets Kicker Cover Gasket 1936-1986 Harley-Davidson Big Twin 4 Speeds OEM# 3329536
$4.00

Colony #2294-14 Inner Primary Mounting Kit 1999-2005 Harley-Davidson Dyna Glide 2000-2006 Softail 2001-2006 FLT
1 review $24.00

Colony #9873-16 Inner Primary Mounting Kit 1994-1999 Harley-Davidson Softail 1994-1998 Dyna Glide - CAD Plated
1 review $24.00

Colony #8811-16 Brake Drum Bolt Kit Rear Stock 1968-1978 Harley-Davidson Sportster OEM #3970B - Chrome Plated
6 reviews $24.00

Standard Motorcycle Products Points & Condenser Kit 1958-1969 Harley-Davidson XL With Magneto
$23.95

Goodridge Universal Braided Stainless Brake Line - 11" - Clear Coated
$23.95

Goodridge P593-03-M12C 35 Degree 12mm Banjo Fitting - Stainless Steel
$23.95

Colony #2325-3 Oil Pump Plug Kit CAD 1952-54 Harley Davidson K KH — Colony #2325-3 Oil Pump Plug Kit 1952-1954 Harley-Davidson K/KH - CAD Plated
1 review $23.93

Colony #7803-11 Acorn Nut Kickstand Mounting Kit 1936-1986 Big Twin 4 Speeds (Except Softail) - Chrome Plated
5 reviews $23.91

Colony #7619-1 Custom Stem Nut 1971-Up Harley-Davidson 1979-Up Sportster - Chrome Plated
1 review $23.91

Drag Specialties 40A Circuit Breaker 1970-1999 Harley-Davidson Big Twin/XL 1999 Twin Cam
$7.95

Colony #8761-7 Timing Cover Knurled Allen Screw Kit 1970-1992 Harley-Davidson Shovelhead/Evo - Chrome Plated
2 reviews $11.90

Colony #2871-1 Rear Axle Spacer 1952-1978 Harley-Davidson K/KH/XL - Chrome Plated
$23.65

Colony #9020-2 Rear Chain Adjuster - 1952-1978 Harley-Davidson Sportster - CAD Plated
4 reviews $23.54

Cycle Standard Screw-In Harley Stock Style Non-Vented Gas Cap - Left Side - 1996 & up - Black
$23.51

Colony #3371-3 Brake Lever Stud Kit Harley-Davidson 1926-1934 Singles 1926-1931 45 Twins - Parkerized
$23.38

Colony #2921-2 Spring Retainer & Acorn Nut Set 1936-1948 Harley-Davidson Big Twin Springers 1936-1952 45s 1953-1954 Servi-car - Chrome Plated
2 reviews $23.38

Drag Specialties Universal 9 inch Battery Cable
$23.27

Colony #3783-4 Kick Starter Tripper Bolt/Nut Kit 1926-1940 Harley-Davidson 45's - Parkerized
$23.18

Colony #9919-3 Transmission Bottom Stud Kit 1929-Up Harley-Davidson 45's
$23.18

Colony #7716-2 Dash Cover Mounting Center Screw & Stud Kit All 1947-1967 Harley-Davidson
2 reviews $23.18

Cycle Standard Spark Plug Wire Separators - Aluminum
$23.16

Colony #9103-4 Shift Rod End Bolt Kit 1936-1954 Harley-Davidson Handshift 1951-1964 Foot Shift - Chrome Plated
$11.56

Colony #3590-3 Oil Line Nuts for 3/8 inch Rubber Lines 1915-1964 Harley-Davidson - CAD Plated
1 review $23.10

Colony #3545-3 Oil Line Nuts With Nipple For Rubber Lines OEM #3581-15 - CAD Plated
1 review $23.10

Colony #2765-12 Clutch Backing Plate Stud Spacer Kit 1979-1984 Harley-Davidson Sportster
3 reviews $23.10

CUSTOM MOTORCYCLE PARTS FOR HARLEY, TRIUMPH, AND BSA BUILDS The parts you choose define the bike. OEM keeps it stock. Aftermarket opens up fitment, finish, and function options the factory never offered. Whether you are sourcing a direct replaceme...

CUSTOM MOTORCYCLE PARTS FOR HARLEY, TRIUMPH, AND BSA BUILDS

The parts you choose define the bike. OEM keeps it stock. Aftermarket opens up fitment, finish, and function options the factory never offered. Whether you are sourcing a direct replacement for a worn component or tracking down a specific piece to finish a chopper or bobber build, the catalog here covers custom Harley parts, BSA, and vintage Triumph across hundreds of categories.

WHY BUILDERS GO AFTERMARKET

Stock parts do the job they were designed for. Aftermarket custom motorcycle parts do what the builder needs:

Fitment Where OEM Falls Short: Finding correct OEM components for older Harley Big Twin, BSA, or vintage Triumph motorcycle parts gets harder every year. Aftermarket and reproduction parts fill those gaps with components built to the same spec or better.
Material and Finish Options: Many aftermarket parts come in finishes the factory never offered, including billet aluminum, stainless, black oxide, and chrome. The part matches the direction of the build rather than fighting it.
Universal Parts for Custom Work: Raw, unfinished, and universal parts give you a starting point to cut, shape, and mount to your specific frame and geometry. That is something a stock replacement never offers, and it is where bobber motorcycle parts and chopper builds get interesting.
Cost and Availability on Older Platforms: For british motorcycle parts and vintage Triumph or older Harley platforms, reproduction aftermarket parts are often the more practical choice on both availability and price.

BRANDS AND WHAT WE STOCK

The catalog covers hardware, fabrication parts, engine components, controls, lighting, and everything in between. Key brands include Colony for hardware and fasteners and Mid-USA for drivetrain and engine components. Fitment data is listed on each product page. If you are not sure what fits your year and model, the team is reachable by chat, phone, or email.

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