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.

Custom Motorcycle Parts

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BEST SELLING BRANDS

TOP Custom Motorcycle Parts

Drag Specialties Wheel Bearings and Races - Replaces Harley-Davidson OEM #9276A/B/9252A
1 review $44.32

Drag Specialties 1 inch Wheel Bearings and Races - Replaces Harley-Davidson OEM #9247
2 reviews $41.82

Drag Specialties Universal 20 inch Battery Cable
$29.63

Drag Specialties Universal 18 inch Battery Cable
$29.63

Drag Specialties Universal 15 inch Battery Cable
$31.75

K&N Air Filters Recharger Air Filter Cleaning Kit
$36.99

Colony #3665-5 Transmission Shifter Cover & Speedometer Sensor Allen Screw Kit 1987-1997 Harley-Davidson FX/FL/Softail
$6.77

Colony #3661-18 Rear Sprocket Rivets 1935-1952 Harley-Davidson 45s
$15.68

Colony #3657-8 Circuit Breaker To Coil Wire Fastener Assembly 1936-1948 Harley-Davidson All Twins
$9.90

Colony #3586-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 1 inch Thick - Chrome Plated
$11.90

Colony #3585-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 7/8 inch Thick - Chrome Plated
$11.17

Colony #3584-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 3/4 inch Thick - Chrome Plated
$10.42

Colony #3583-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 5/8 inch Thick - Chrome Plated
1 review $9.68

Colony #3582-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 1/2 inch Thick - Chrome Plated
$8.93

Colony #3581-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 3/8 inch Thick - Chrome Plated
$8.20

Colony #3580-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 1/4 inch Thick - Chrome Plated
$7.45

Colony #3563-1 Stem Crown Nut 1936-1938 Harley-Davidson Big Twin Springer - CAD Plated
$63.80

Colony #3401-16 Rocker Cover Allen Screw Kit 1985-Up Harley-Davidson FL/FX 1986-Up XL - CAD Plated
$13.55

Colony #3396-5 Sprocket Cover Allen Screw Kit 1977-1985 Harley-Davidson Sportster - CAD Plated
$6.29

Colony #3395-8 Oil Pump Mounting Kit 1991-2003 Harley-Davidson Sportster - CAD Plated
$5.32

Arlen Ness Big Sucker Stage 1 Air Filter Kit - Black - 1993-1999 Harley-Davidson Evolution Big Twin
1 review $215.96 $239.95

Gasbox Full Rigid Frame 1986-2003 Harley-Davidson Sportsters - Frisco Tank Mounts
2 reviews $1,199.00

Prism Supply Co. Sling Shot Hydraulic Brake Pedal Kit - Harley-Davidson Generator Engine - Stainless Steel
$249.99

Mid-USA Four Piston Brake Caliper - Replacement Caliper Hardware Kit
$21.81

Martian Machine Penis Cast Aluminum Foot Pegs
$65.00

Martian Machine Highway Pegs - Harley-Davidson Sporsters - Black Powdercoat
1 review $185.71

Martian Machine Highway Pegs - Harley-Davidson Sporsters - Raw Aluminum
$185.71

Martian Machine Skid Bars Handlebars - Black Powdercoat
2 reviews $120.00

Martian Machine Skid Bars Handlebars - Raw Steel
$120.00

Martian Machine Rabbit Ears Handlebars - Black Powdercoat
$120.00

Martian Machine Rabbit Ears Handlebars - Raw Steel
3 reviews $120.00

Martian Machine Sideways Can Cast Aluminum Points Cover - Twin Cam
2 reviews $45.00

Martian Machine Sideways Can Cast Aluminum Points Cover - Horizontal
1 review $45.00

Martian Machine Sideways Can Cast Aluminum Points Cover - Veritcal
$45.00

Martian Machine Can Cast Aluminum Points Cover - Horizontal
6 reviews $45.00

Martian Machine Can Cast Aluminum Points Cover - Veritcal
2 reviews $45.00

Martian Machine Spiral Cast Aluminum Points Cover - Twin Cam
$45.00

Martian Machine Spiral Cast Aluminum Points Cover - Veritcal
1 review $45.00

Martian Machine Heart Cast Aluminum Points Cover - M8
$45.00

Colony #3651-2 Clutch Adjusting Springs L1984-1993 Harley-Davidson Sportster XL
$8.80

Colony #3648-16 Headbolt Set 1957-1972 Harley-Davidson Sportster - CAD Plated
$51.78

Colony #3618-4 Reproduction Spacers Harley-Davidson OEM #36869-48 - 4 pack - Parkerized
$10.89

Colony #3393-10 Handlebar Lever Mounting Screw Kit 1982-1995 Harley-Davidson Big Twin & Sportsters
1 review $11.62

Colony #3392-10 Handlebar Lever Mounting Screw Kit 1973-1981 Harley-Davidson Big Twin & Sportsters
1 review $7.49

Colony #3391-4 Handlebar Lever Mounting Screw Kit Pre-1972 Harley-Davidson Big Twin & Sportsters
$3.87

Cycle Electric Generator DGV-5006H 6 Volt for 1936-1957 Harley-Davidsons w/Heli Coils
2 reviews $569.01 $609.10

Cycle Electric Generator DGV-2578-H 6 Volt for 1936-1957 Harley-Davidsons w/Heli Coils
1 review $414.43 $428.72

Klock Werks Sport Flare Windshield - 6 inch - Black - 2015-Up Harley-Davidson FLTR Models
$199.95

Colony #3640-2 Generator Brush Cover Strap/Spring Kit 1958-1965 Harley-Davidson FL/XL/Servi-Car
$22.00

Colony #3638-4 Pushrod Cover Seal Kit 1991-2003 Harley-Davidson Sportster
$11.00

Colony #3636-4 Kickstand Leg Stop Kit 1936-1984 Harley-Davidson Big Twins - CAD Plated
$16.78

Colony #3635-4 Kickstand Leg Stop Kit 1936-1984 Harley-Davidson Big Twins - Parkerized
$16.78

Colony #3634-2 Reproduction Footrests 1952-1990 Harley-Davidson K/KH/XL 1971-1991 FX
$35.00

Colony #3632-10 Front Stand Catch Mounting Kit 1936-1948 Harley-Davidson Big Twins 1936-1957 Servi-Car 1936-1952 45's - Parkerized
$7.43

Colony #3629-2 Speedo Drive Unit Retainer 1937-1952 Harley-Davidson WL - Parkerized
$7.43

Colony #3621-4 Brake Light Switch Mounting Kit 1939-1957 Harley-Davidson Big Twins - Chrome Plated
$10.45

Colony #3619-1 Cylinder Bracket 1932-1950 Harley-Davidson 45's w/Cast Iron Heads - Parkerized
$45.00

FNA Custom Cycle Tite Seal Kit Replacement Seals
2 reviews $20.00

Joker Machine Indicator Light Handlebar Clamp - Black
$90.95

Mid-USA Indian Style Leaf Spring Front End
2 reviews $987.65

Shinko Motorcycle Tires SR777 Rear Motorcycle Tire - 130/90B16
2 reviews $156.95

Shinko Motorcycle Tires SR777 Front Motorcycle Tire - 90/90-21
2 reviews $108.99

The Speed Merchant Cruiser Foot Pegs - Raw
$152.96 $169.95

The Speed Merchant 39mm Speed Triple Trees - Black - 1991-05 Harley-Davidson FXD 1988-20 XL 1988-00 FXR
$836.96 $929.95

The Speed Merchant 49 mm Fork Preload Adjuster - Gold Finish
1 review $161.96 $179.95

The Speed Merchant 39 mm Fork Preload Adjuster - Black Anodized Finish
$152.96 $169.95

Drag Specialties Solo Seat - Diamond - 1982-2003 Harley-Davidson Sportster XL
$311.95

Drag Specialties Solo Seat - Smooth - 1982-2003 Harley-Davidson Sportster XL
$280.95

Drag Specialties EZ-On Solo Seat - Smooth - 1982-2000 Harley-Davidson FXR
$354.95

Drag Specialties Solo Seat - Smooth - 1958-1984 Harley-Davidson FX/FL
$362.95

Drag Specialties Solo Seat - Smooth - 1984-99 Harley-Davidson FXST/FLST
$353.95

Drag Specialties Low Profile Double Bucket 2-Up Pillow Seat - 1982-2003 Harley-Davidson Sportster XL

$393.95

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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Custom Motorcycle Parts FAQ

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