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

Coker Tire Firestone ANS Motorcycle Tire 4.50-18
$300.98

Colony #3719-4 Fuel Tank Rubber Grommet Kit 2018-Up Harley-Davidson Softails
$20.00

Colony #3717-16 Black Headbolt Set 1973-1985 Harley-Davidson Sportster
$45.27

Colony #3716-2 Battery Mat Set 1915-1964 Harley-Davidson 6 Volt Battery Models
1 review $11.00

Colony #3714-3 Instrument Panel Cover Plate Right Side 1939-1946 Harley-Davidson All Models - Parkerized
1 review $9.90

Colony #3713-3 Instrument Panel Cover Plate Right Side 1939-1946 Harley-Davidson All Models - CAD Plated
$9.90

Colony #3697-4 Exhaust Port Nuts 1984-1999 Harley-Davidson Big Twin 1986-Up XL 1999-Up Twin Cam - Zinc Plated
2 reviews $4.40

Colony #3558-1 Sprocket Shaft Seal 1939-1973 Harley-Davidson 45's
$6.60

Haifley Seats Bates Style Pillion P-Pad - Tuck-n-Roll - Black & White
$160.00

Haifley Seats Bates Style Pillion P-Pad - Tuck-n-Roll - White
$160.00

Haifley Seats Bates Style 1 inch Tuck-n-Roll Solo Seat - Black & White
1 review $300.00

Haifley Seats Bates Style 1 inch Tuck-n-Roll Solo Seat - White
1 review $300.00

Award Cycle Finned Timing Cover - Triumph Pre-Unit Generator Models
$749.99

Kustom Tech Vintage Line Shifter/Brake Peg - Black & Brass
$131.68

Kustom Tech Vintage Line Shifter/Brake Peg - Auminum & Brass
$103.13

Kustom Tech Vintage Line Foot Pegs - Black & Brass
$371.20

Kustom Tech Vintage Line Foot Pegs - Auminum & Brass
$331.56

Kustom Tech Vintage Line Forward Controls - Black & Brass - 1986-99 Harley-Davidson FL/FXST
$1,554.67

Kustom Tech Vintage Line Forward Controls - Aluminum & Brass - 1986-99 Harley-Davidson FL/FXST
1 review $1,396.03

Drag Specialties Inner Primary Mainshaft Bearing Seal Kit 1989-99 Harley-Davidson Big Twin 99-06 Twin Cam
1 review $61.83

Drag Specialties Swing Arm Bearing Kit 2000-17 Harley-Davidson Softail Models
$63.34

Drag Specialties Swing Arm Bearing Kit 1984-99 Harley-Davidson FXST/FLST
$68.75

Drag Specialties Swing Arm Bearing Kit 2002-21 Harley-Davidson FLT/FLHT/FLHR/FLHX/FLTR/FLTRU/FLTRK
$64.65

Belt Drives LTD. 8mm/3 inch Primary Open Belt Drive - Kick Start - Spline Shaft - 1955-1984 Harley-Davidson Big Twin
1 review $657.35 $691.95

Mid-USA 21 x 2.15 Chrome Front Spool Wheel
4 reviews $191.92 $219.25

Mid-USA 16 x 3 Black Antique Style Front Spool Wheel
$199.99

Mid-USA 21 x 2.15 Chrome Antique Style Front Spool Wheel
$199.99

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

Drag Specialties Wheel Bearings and Races - Replaces Harley-Davidson OEM #9009
$33.57

Drag Specialties Universal 20 inch Battery Cable
$29.63

Drag Specialties Universal 11 inch Battery Cable
$28.57

Cycle Standard Fuel Injection Fuel Line Assembly +3 inch - 2007-2022 Harley-Davidson Sportster
1 review $66.27

Colony #3666-13 Transmission Side Cover Allen Screw Kit 1987-2006 Harley-Davidson FX/FL/Softail 1991-2005 Dyna - CAD Plated
$20.32

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 #3658-8 Circuit Breaker To Coil Wire Fastener Assembly 1949-1964 Harley-Davidson Twins/K/KH/Sportster
$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 #3580-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 1/4 inch Thick - Chrome Plated
$7.45

Colony #3579-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 1/8 inch Thick - Chrome Plated
$5.95

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

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

Colony #3394-10 Oil Pump Mounting Kit 1977-1990 Harley-Davidson Sportster - CAD Plated
$6.29

Lowbrow Customs Weld-On Hardtail Frame for 2004-2022 Harley-Davidson Sportster
9 reviews $468.00

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

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

Martian Machine Barefoot Cast Aluminum Kicker Pedal
1 review $120.00

Martian Machine Penis Cast Aluminum Foot Pegs
$65.00

Martian Machine Highway Pegs - Harley-Davidson Sporsters - Black Powdercoat
1 review $185.00

Martian Machine Highway Pegs - Harley-Davidson Sporsters - Raw Aluminum
$185.00

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 - M8
$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 - M8
1 review $45.00

Martian Machine Can Cast Aluminum Points Cover - Twin Cam
3 reviews $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 - Veritcal
1 review $45.00

Martian Machine Heart Cast Aluminum Points Cover - M8
$45.00

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

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

Colony #3650-1 Jiffy Stand Spring Plate 1930-1952 Harley-Davidson 45 Twins 1930-1934 Singles - Parkerized
$16.50

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

Colony #3645-5 Ignition Coil Mounting Plate Kit 1985-2003 Harley-Davidson XL 1994-2001 Touring 1991-1999 Softail 1991-1994 Dyna - Zinc Plated
$7.70

Colony #3642-2 Buddy Seat Auxiliary Spring Clip - Heavy - 1936-1964 Harley-Davidson Big Twins - Parkerized
$30.00

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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