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 #2585-7 Steering Damper Upper Kit 1937-1957 Harley-Davidson 45s 1953-1957 Servi-car - Parkerized
$55.00

Colony #2479-2 Control Coil Adjusting Sleve 1928-1936 Harley-Davidson with Throttle Controlled Oilers - Parkerized
$13.92

Colony #2468-8-P Transmission to Motor Mount Smooth Allen Kit 2007-Up Harley-Davidson Softail/Dyna/FLT - Chrome Plated
$14.34

Colony #2381-24 Transmission Side Cover Hardware Kit 1915-1930 Harley-Davidson Twins - Nickel Plated
$30.36

Colony #2229-16 Motor Mount Kit Acorn 2004-Up Harley-Davidson Sportster - Chrome Plated
$55.28

Colony #2223-11 Cam Cover Acorn Screw Kit 2004-Up Harley-Davidson Sportster - CAD Plated
$35.70

Colony #2171-17-P Clutch Cover Mounting Kit Smooth Allen 2002-Up Harley-Davidson VRSC - Chrome Plated
$29.78

Colony #2168-22-P Cam Cover Mounting Kit Smooth Allen 2002-Up Harley-Davidson VRSC - CAD Plated
$39.25

Colony #8521 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1989-1991 Softail 91 Dyna Glide - Chrome Plated
$311.38

Colony #8520 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1987-1988 Softail - Chrome Plated
$311.38

Colony #8519 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1986-1990 Sportster - Chrome Plated
$252.00

Colony #8517 Complete Show Bike Kit Cap Style Hardware Harley-Davidson Evolution w 4 Speed - Chrome Plated
$240.78

Colony #8516 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1979-1984 FLT - Chrome Plated
$414.58

Colony #8506 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1940-1947 Knucklehead - Chrome Plated
$395.76

Colony #8504 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1977-1985 Sportster - Chrome Plated
$341.08

Colony #8503 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1974-1976 Sportster - Chrome Plated
$339.27

Colony #8502 Complete Show Bike Kit Cap Style Hardware Harley-Davidson 1971-1973 Sportster - Chrome Plated
$339.27

Colony #7935 Complete Show Bike Kit Acorn Hardware Harley-Davidson 2004-up Sportster - Chrome Plated
$254.93

Colony #7934 Complete Show Bike Kit Acorn Hardware Harley-Davidson 2006-up Dyna - Chrome Plated
$313.51

Colony #7932 Complete Show Bike Kit Acorn Hardware Harley-Davidson 2007-up FLT - Chrome Plated
$317.52

Colony #7931 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1996-1998 FLT/FXR - Chrome Plated
$301.84

Colony #7930 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1992-1995 FLT/FXR - Chrome Plated
$307.25

Colony #7929 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1987-1991 FLT/FXR - Chrome Plated
$304.55

Colony #7928 Complete Show Bike Kit Acorn Hardware Harley-Davidson 2000-2006 Softail Twin Cam - Chrome Plated
$346.14

Colony #7926 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1999-2006 FLT - Chrome Plated
$320.07

Colony #7925 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1999-2005 Twin Cam Dyna - Chrome Plated
$330.22

Colony #7924 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1996-1999 Softail 1996-1998 Dyna Glide - Chrome Plated
$320.07

Colony #7923 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1992-1995 Softail Dyna Glide - Chrome Plated
$325.86

Colony #7921 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1989-1991 Softail 91 Dyna Glide - Chrome Plated
$311.38

Colony #7920 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1987-1988 Softail - Chrome Plated
$311.38

Colony #7909 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1966-1969 Shovelhead - Chrome Plated
$397.20

Colony #7905 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1936-1939 Knucklehead - Chrome Plated
$395.76

Colony #7904 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1977-1985 Sportster - Chrome Plated
$341.08

Colony #7900 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1957-1964 Sportster - Chrome Plated
$322.26

Colony #3084-4 Gear and Sprocket Shaft Nut Lockwasher Kit 1929-1973 Harley-Davidson 45s
$6.96

Colony #3078-18 Exhaust System Chrome Mounting Bolt Kit Harley 45s 32-73
$23.65

Colony #3077-18 Exhaust System Parkerized Mounting Bolt Kit Harley 45s 32-73
$21.12

Colony #3442-14 Transmission Side Cover Kit 2017-Up Harley-Davidson Touring Models - Chrome Plated
$43.65

Colony #3441-13 Motor Mounting Kit 2017-Up Harley-Davidson Touring Models - Chrome Plated
$24.88

Colony #3440-12 Motor Case Mounting Kit 2017-Up Harley-Davidson Touring Models - Chrome Plated
$45.01

Colony #3439-20 Rocker Box Mounting Kit 2017-Up Harley-Davidson Touring Models - Chrome Plated
$51.04

Colony #3374-4 Triple Clamp Bolt Kit 1932-1936 Harley-Davidson 45"/74"/80" Twins 1932-1934 C Singles - Parkerized
$39.60

Colony #3327-4 Shift Tower Frame Bracket Cap Bolt Kit 1915-1929 Harley-Davidson J/JD - Parkerized
$10.29

Colony #3351-4 Rocker Arm Thrust Washer Kit 1936-1947 Harley-Davidson Knucklehead
$12.09

Colony #3347-12 Ignition Switch Mounting Kit 1939-1946 Harley-Davidson Twins - Parkerized
$8.71

Colony #3338-4 Clutch Spring Guide Stud Kit 1934-1940 Harley-Davidson 45s
$30.00

Colony #3322-1 Rear Axle Spacer 1952-1954 Harley-Davidson K/KH OEM #41600-52 - Parkerized
$19.36

Colony #3315-2 Control Coil End Plug 1937-1948 Harley-Davidson Big Twins 1940-1948 45 Solo/Servi-car
$16.50

Colony #3312-14 Seat Spring Mount Kit 1965-1967 Harley-Davidson FL/FLH
$23.76

Colony #3303-5 Fork Bracket Bolt and Clip Kit 1950-1977 Harley-Davidson FL/FLH - Parkerized
$56.65

Colony #3307-4 Intake and Exhaust Rocker Arm Cover Return Oil Line Nuts 1938-1947 Harley-Davidson Knucklehead
$21.56

Colony #3272-1 Relief Pipe Nut 1926-1931 Harley-Davidson Singles 1929-1931 45 Twins - CAD Plated
$10.89

Colony #3290-1 Control Coil Clamp 1930-1936 Harley-Davidson V/VL 1930-1931 D/DL/DLD 1932-1936 R/RL/RLD 1937-1940 WL/G - Parkerized
$21.78

Colony #3285-18 Head Bolt Aluminum Washer Set Harley-Davidson Flathead (Aluminum Head) OEM #16822-39 - CAD Plated
$44.00

Colony #3123-20 Knurled Allen Rocker Cover Mounting Kit 2017-Up Harley-Davidson Touring Models - Chrome Plated
$31.68

Colony #3123-20-P Smooth Head Allen Rocker Cover Mounting Kit 2017-Up Harley-Davidson Touring Models - Chrome Plated
$44.44

Colony #3251-2 Steering Damper Adjusting Screw and Locknut Kit 1960-1984 Harley-Davidson Big Twin FL Models - CAD Plated
$19.36

Colony #3256-8 Saddle Bar To Seat Mount Kit 1952-1970 Harley-Davidson K/KH/XL/XLH/XLCH - CAD Plated
$13.74

Colony #3226-4 Seat Post Bushing Set 1952-1970 Harley-Davidson K/KH/XL/XLH/XLCH
$22.00

Colony #3212-2 Front Cylinder Head Bolt 1942 Harley-Davidson WLA - Parkerized
$10.89

Colony #3204-4 Switch Box Fastening Bolt Kit 1929-1931 Harley-Davidson D/DL/DLD 1930-1936 V/VL/VLD/VLE/VLH 1932-1936 R/RL/RLD - Nickle Plated
$16.35

Colony #3166-1 Timer Screw 1970-E1978 Harley-Davidson FL 1971-E1978 FX/XL - Zinc Plated
$9.68

Colony #41695-07 Axle/Wheel Spacer 1-1/2 x 1 x .520 Harley-Davidson OEM #41695-07 - Chrome Plated
$9.05

Colony #41505-07 Axle/Wheel Spacer 2-7/16 x 1 x .790 Harley-Davidson OEM #41505-07 - Chrome Plated
$20.88

Colony #3213-4 Front Hub Cone Lock Washers & Spring Rings Kit 1914-1929 Harley-Davidson Twins - CAD Plated
$20.57

Colony #3191-4 Rocker Arm Shaft Nut Set 1936-1947 Harley-Davidson Knuckleheads - Parkerized
$65.99

Colony #3190-4 Rocker Arm Shaft Nut Set 1936-1947 Harley-Davidson Knuckleheads - CAD Plated
$65.99

Colony #3173-8 Footboard Mounting Kit 1982-Up Harley-Davidson FL - Zinc Plated
$15.13

Colony #9821-4-P Oil Filter Adaptor Mounting Kit Smooth Allen 1992-Up Harley-Davidson Big Twin - Chrome Plated
$5.58

Colony #3186-1 Upper Fork Bearing Adjusting Nut 2001-2007 Harley-Davidson FXSTD 2008-2010 FXCW 2001-Up FXS 2005-2008 V-rod - Zinc Plated
$12.10

Colony #3184-4 Battery Wing Nuts 1/4-20 OEM #4409-24 - CAD Plated
$4.84

Colony #3164-1 Carb Venturi Oversized .025 OEM #27363-30
$41.97

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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