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

Colony #3729-2 Crankcase Bolt Set 1930-1978 Harley-Davidson Big Twins - Parkerized
$14.30

Colony #3725-12 Center Stand Mounting Kit 1957-1981 Harley-Davidson Sportster XL
$56.68

Colony #3704-2 Brake Caliper Bleeder Screws 2009-Up Harley-Davidson Touring 2008-Up V-Rod - Black Oxide
1 review $8.47

Colony #3727-11 Battery Box Mounting Kit 1930-1936 Harley-Davidson VL - Parkerized
$20.90

Arrow Manufacturing Dyme Piece Tail Light
$285.00

LePera Signature II Two Piece Seat - Diamond - Rigid Frame
$479.00

LePera Baron II One Piece Seat - Pleated - Rigid Frame
1 review $479.00

LePera Cobra Pillion P-Pad - Smooth
$192.00

LePera King Cobra Seat - Smooth - 1982-2003 Harley-Davidson Sportsters
$433.00

LePera Cobra Seat - Smooth - Rigid Frame
1 review $433.00

LePera Kickflip Seat - Diamond - 2010-2023 Harley-Davidson Sportsters
$548.00

LePera Sprocket Solo Seat - Smooth - 2004-2023 Harley-Davidson Sportsters
$364.00

LePera Sprocket Solo Seat - Diamond - 2004-2023 Harley-Davidson Sportsters
$410.00

LePera Cobra Full-Length Seat - Diamond - 2004-2023 Harley-Davidson Sportsters
$479.00

LePera Cherokee Seat - Smooth - 2004-2023 Harley-Davidson Sportsters
$479.00

LePera Cherokee Seat - Pleated - 2004-2023 Harley-Davidson Sportsters
1 review $548.00

LePera Cherokee Seat - Diamond - 2004-2023 Harley-Davidson Sportsters
$548.00

Avon Tyres Avon Safety Mileage MKII 5.00-16 Tire
19 reviews $292.44

Lowbrow Customs Moto Luggage Rack - Right Side - 2006-2017 Harley-Davidson Dyna
$89.24 $104.99

Lowbrow Customs Moto Luggage Rack - Left Side - 2006-2017 Harley-Davidson Dyna
$89.24 $104.99

Lowbrow Customs Skateboard Carrier Rack 2004-2022 Harley-Davidson Sportsters
1 review $168.66

Lowbrow Customs Skateboard Carrier Rack 1994-2003 Harley-Davidson Sportsters
$168.66

Cycle Standard Clutch Friction Disc Set 1971-e1984 Harley-Davidson Sportster XL
$45.15

Cycle Standard Steel Clutch Plate Set 1971-e1984 Harley-Davidson Sportster XL
$82.75

Cycle Standard Clutch Shell With Starter Ring 1970-E1984 Harley-Davidson Big Twins - OEM #37702-70A
$266.91

Cycle Standard Clutch Shell 1941-1964 Harley-Davidson Big Twins - OEM #37703-41
$202.30

Cycle Standard Tapered T-Bar Extensions - 1" High/1" Handlebars - Black
$35.01

Cycle Standard Tapered T-Bar Extensions - 1" High/1" Handlebars - Chrome
$35.01

Cycle Standard Chrome Rear Axle Kit 2008-Up Harley-Davidson Sportster XL
$112.13

Cycle Standard Chrome Rear Axle Kit 1979-2003 Harley-Davidson Sportster XL
3 reviews $54.45

Cycle Standard Primary Chain Adjuster Pad - 1958-1980 Harley-Davidson Sportster XL
$8.15

Cycle Standard Derby Cover - Gloss Black - 2006-2021 Harley-Davidson Sportster XL
$47.75

Gasbox Gasbox "Lorain" Sportsters Full Frame for 1986-2003 Harley-Davidson
3 reviews $1,499.00

Unity Manufacturing TUFF Stainless Steel Brake Rotor - 11.5 inch - Rear
$192.86

Unity Manufacturing TUFF Stainless Steel Brake Rotor - 11.5 inch - Front
$192.86

Unity Manufacturing Solid Stainless Steel Brake Rotor - 11.5 inch - Rear
$189.99

Unity Manufacturing Solid Stainless Steel Brake Rotor - 10 inch - Rear
$189.99

Unity Manufacturing Solid Stainless Steel Brake Rotor - 10 inch - Front
$189.99

Cycle Standard 5-1/2 inch Pullback Handlebar Riser Set - Black
$106.42

Cycle Standard Replacement Primary Inspection Cover Gasket - 2004-2021 Harley-Davidson Sportster XL
2 reviews $7.58

Cycle Standard Handlebar Clamp - Smooth - Black
$28.12

Lowbrow Customs Lowbrow Customs Horseshoe Oil Tank Upper Tab Mounting Kit - 2004-2022 Sportster Hardtail
$15.09

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

Colony #3708-1 Instrument Panel Cover Plate Left Side 1939-1946 Harley-Davidson All Models - CAD Plated
$7.70

Colony #3707-1 Instrument Panel Cover Plate Right Side 1947-1964 Harley-Davidson All Models - CAD Plated
1 review $9.90

Colony #3699-2 Shock Absorber Dirt Seals 1956-1984 Harley-Davidson FL/FLH 1956-1972 KH/XL/XLH/XLCH
$8.80

Colony #3696-4 Exhaust Port Nuts 1984-1999 Harley-Davidson Big Twin 1986-Up XL 1999-Up Twin Cam - Chrome Plated
1 review $6.05

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

Colony #3556-1 Sprocket Shaft Seal 1940-1954 Harley-Davidson Big Twins
$6.60

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

Lowbrow Customs Sportster Skid Plate - Black - Harley-Davidson Sportster 2004-2022
5 reviews $197.95

Lowbrow Customs Sportster Skid Plate - Stainless - Harley-Davidson Sportster 2004-2022
1 review $197.95

Dill Air Controls Rubber Valve Stem - Pull-in TR-413 - Chrome
$4.95

Dill Air Controls Rubber Valve Stem - Pull-in TR-412 - Black
$3.95

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

James Gaskets Top End Gasket Kit 2007-Up Harley-Davidson Sportster
$119.93

Lowbrow Customs Cast Aluminum Knurled Oil Tank Plug - Semi Polished
4 reviews $25.26

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 Swing Arm Bearing Kit 1958-86 Harley-Davidson FX/FXWG/FLH (except Softail, FXR, FLT)
1 review $41.91

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

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

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

Drag Specialties Wheel Bearings and Races - Replaces Harley-Davidson OEM #43577-67
$50.70

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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