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

Bare Knuckle Performance Stubby Shift Knob - Polished
$24.99

No School Choppers Replacement Tail Light License Plate Lens Gasket 1928 - 1932 Ford Duolamp
$2.41

No School Choppers 1928 - 1932 Ford Duolamp Tail Light Replacement Stainless Steel Bezel
$8.46

No School Choppers 1928 - 1932 12V LED Black Out Ford Duolamp - Original Red Lens - Model A Stainless Steel Tail Light
$97.73

Lowbrow Customs Crescent Moon Motorcycle Mirror - Clamp On - Chrome
1 review $47.11

Cycle Standard Gloss Black Kickstand - 2004-2019 Harley-Davidson XL Sportster Models
$74.80

Morris Magneto "Sparky" Spark Tester Keychain
$34.00

Morris Magneto Replacement Bakelite Magneto Cap - Red
$49.39

American Prime Mfg. Complete Comp Master Clutch fits 1999-2006 Harley-Davidson EVO & Twin Cam Big Twins
$634.47

American Prime Mfg. Complete Comp Master Clutch fits 1990-1997 Harley-Davidson Big Twin
$622.33

American Prime Mfg. Complete Comp Master Clutch fits 1936-1984 Harley-Davidson Pre-EVO Big Twin
2 reviews $639.76

Bare Knuckle Performance SS2 Solo Seat Springs - Barrel Style - 4 inch Electropolished Stainless Steel
$59.00

Gigacycle Garage Gigacycle Garage FXR Side Panel Screws & Seat Screw for Ness Style side panels
$131.43

Gigacycle Garage Gigacycle Garage Left Side Non-Vented Gas Cap for 1992-Up Harley-Davidsons
$107.14

Tokico Tokico 4 Piston Remanufactured Brake Caliper - Left Side
$261.07

Gasbox Upswept Exhaust Pipe Set for 1948-1965 Harley-Davidson Panhead Rigid Applications
$389.95

Lectron Lectron Billetron Carburetor for 100-124 Cubic Inch Harley-Davidsons
$899.00

Airspeed Cycles Pullback T-Bar Handlebars - 6 inch Rise - 1 inch - Stainless Steel
$255.00

Lowbrow Customs Axle Plate Offset License Plate Bracket for 1936 - 1957 Harley-Davidson Big Twin Rigid Frames
$58.41

S&S Cycle Super E Carburetor Kit 1986-1990 Harley-Davidson Sportster XL
1 review $716.36 $795.95

Drag Specialties 12 Volt Mini Dual-Fire Ignition Coil - 5 ohm
$71.64

Prism Supply Co. Motor Mount Mid-Pegs for Harley-Davidson Big Twins - Powder Coated Black
$94.99

Prism Supply Co. Blade Style Push-in Oil Plug - Tumbled
$54.99

Prism Supply Co. Darlington Air Cleaner - S&S Super E/G - Brushed Aluminum
$224.99

Prism Supply Co. Darlington Air Cleaner - S&S Super E/G - Polished
$229.99

Prism Supply Co. Darlington Air Cleaner - CV Carburetor - Brushed Aluminum
$224.99

Prism Supply Co. Prism Supply Co. Petcock Rebuild Kit
$12.99

Progressive Suspension 412 Series 11" Chrome Shocks - Full Cover 1986-2003 Harley-Davidson XL
$454.95

LePera Pillion P-Pad - Smooth for Bare Bones Solo Seats - fits 1984-1999 Harley-Davidson Softail
$180.00

LePera Cobra Seat - Smooth - fits 1984-1999 Harley-Davidson Softail
1 review $433.00

Airspeed Cycles High Rise Riserless Tracker Handlebars - 1 inch - Stainless Steel
1 review $255.00

Airspeed Cycles Riserless Tracker Handlebars - 1 inch - Stainless Steel
$255.00

Belt Drives LTD. 2" Open Belt Drive Kit - Black - 1990-2006 Harley-Davidson FXST/FLST
$3,233.51 $3,403.69

Belt Drives LTD. 2" Open Belt Drive Kit - Polished - 1990-2006 Harley-Davidson FXST/FLST
2 reviews $2,958.01 $3,113.69

Colony #3418-24 Spare Wheel Carrier Bracket Bolt Kit 1937-67 Harley-Davidson Sidecars - Parkerized
$27.50

Colony #3406-2 Generator Terminal Bolt Clip and Insulator Kit 1958-1969 Harley-Davidson FL/FLH 1958-65 Servi-car 1958-1981 Sportster
$11.50

Colony #8524 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1996-1999 Softail 1996-1998 Dyna Glide - Chrome Plated
$320.07

Colony #8310 Complete Stock Hardware Kit 1948-1966 Harley-Davidson 2 cycle 125/165/175 cc - CAD Plated
$57.57

Colony #1023 Complete Show Bike Kit Allen Hardware Harley-Davidson 2006-up Dyna - Chrome Plated
$227.39

Colony #1022-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 2004-up Sportster - Chrome Plated
$193.28

Colony #1019 Complete Show Bike Kit Allen Hardware Harley-Davidson 1987-1991 FLT/FXR - Chrome Plated
$208.91

Colony #1018 Complete Show Bike Kit Allen Hardware Harley-Davidson 2000-2006 Twin Cam Softail - Chrome Plated
$218.87

Colony #1016-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 1977-1985 Sportster - Chrome Plated
$220.29

Colony #1012-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 1970-1975 Shovelhead - Chrome Plated
$217.45

Colony #1009 Complete Show Bike Kit Allen Hardware Harley-Davidson 1979-1984 FLT 5 Speed - Chrome Plated
$167.71

Colony #1008-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 1985-1986 Evo 5 Speed - Chrome Plated
$216.03

Colony #1008 Complete Show Bike Kit Allen Hardware Harley-Davidson 1985-1986 Evo 5 Speed - Chrome Plated
$181.91

Colony #1007-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 1984-1986 Evo 4 Speed - Chrome Plated
$227.39

Colony #2931-5 Linkert Carb Support Bracket 1936-1940 Harley-Davidson OHV Big Twins - Parkerized
$19.25

Colony #2923-5 Air Cleaner Mounting Screw Kit Longer Screws 1956-1965 Harley-Davidson Twins - Parkerized
$16.94

Colony #2914-2 Rocker Stud Spacer Kit 1931-1940 Harley-Davidson Big Twin - CAD Plated
$13.31

Colony #2907-2 Oil Tank Filler Cap and Gauge 1936-1940 Harley-Davidson Big Twins - Parkerized
$71.50

Colony #2906-2 Crank Pin Nut Set 1936-1940 Harley-Davidson 61" 1937-1940 Sidevalves
$32.00

Colony #2905-2 Undersized Brass Intake Manifold Seals 1940-1954 Harley-Davidson OHV 1953-1956 K KH
$20.00

Colony #2901-4 Crank Pin Nut Lock Plates 1936-1940 Harley-Davidson Big Twins
$7.26

Colony #2893-3 Starter Crank Clamp Bolt 1941-1967 Harley-Davidson FL/FLH - Chrome Plated
$8.80

Colony #2891-3 Starter Crank Clamp Bolt 1941-1967 Harley-Davidson FL/FLH - Parkerized
$11.00

Colony #2605-3 Footboard Mounting Stud 1914-1922 Harley-Davidson OEM# 2948-14 - Parkerized
$20.90

Colony #2597-17 Legshield Mounting Kit 1940-1942 Harley-Davidson WLA - Parkerized
$29.70

Colony #2582-3 Shifter Lever Stud Kit 1938-1946 Harley-Davidson 45s & Big Twins with Handshift - Parkerized
$16.94

Colony #9990-5 Front Axle Nut Spacer Kit Grooved 1995-1996 Harley-Davidson FXDWG - Chrome Plated
$46.35

Colony #9989-4 Front Axle Nut Spacer Kit Smooth 1994-1999 Harley-Davidson FLHR/FLHRCI - Chrome Plated
$31.87

Colony #9987-4 Rear Wheel Adjusting Screw Flat Head Allen 1991-Up Harley-Davidson Dyna Glide - Chrome Plated
$13.16

Colony #9969-4 Upper Inner Pushrod Covers 1999-Up Harley-Davidson Twin Cam
$39.11

Colony #9961-12 Handlebar Clamp & Gauge Mount Kit Acorn 1995-Up Harley-Davidson FX/XL - Chrome Plated
$15.94

Colony #9849-2 Saddle Front Bolt & Nut Kit 1950-1963 Harley-Davidson Lightweights - CAD Plated
$14.89

Colony #9845-4 Lifter Base Hex Screw Kit 1957-1985 Harley-Davidson Sportster - Chrome Plated
$7.45

Colony #9843-8 Chrome Countersink Washer Set for #10 Flat Head Socket Screws Harley-Davidson - Chrome Plated
$13.94

Colony #9838-10 Transmission Mounting Kit 1929-1974 Harley-Davidson 45's - CAD Plated
$21.35

Colony #9832-28 Rocker Box Hex Screw Kit 1977-1985 Harley-Davidson Sportster - CAD Plated
$25.84

Colony #9826-4 Smooth Front Axle Nut & Spacer Kit 1984-1996 Harley-Davidson FXST/FXSTC/FXSTB 1984-1994 FXDWG/FLT - Chrome Plated
$31.87

Colony #8911-5 Transmission Shifter Cover Cap Head Screw Kit 1987 Harley-Davidson FX/FL - Chrome Plated
$17.52

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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