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 #1002-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 1993-1998 Dyna - Chrome Plated
$220.29

Colony #1002 Complete Show Bike Kit Allen Hardware Harley-Davidson 1993-1998 Dyna - Chrome Plated
$181.91

Colony #1001-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 1999-up Twin Cam 88 FLT - Chrome Plated
$211.75

Colony #9952-11-P Transmission Shifter Cover Smooth Mounting Kit 1998-2006 Harley-Davidson FLT/Softail - Chrome Plated
$14.16

Colony #9948-8-P Electrical Panel Cover Smooth Chrome Allen Mounting Kit Harley Dyna 91-up
$8.56

Colony #9939-6-P Oil Filter Adaptor Mounting Kit Smooth Chrome Allen Harley 99-up Twin Cam Dyna FLT
$6.38

Colony #9933-12-P Intake Manifold to Cylinder Smooth Chrome Allen Kit Harley Sportster 86-87
$12.34

Colony #9927-28-P Upper and Lower Motor Mount Kit Smooth Allen 1984-1999 Harley-Davidson Softail - Chrome Plated
$53.58

Colony #9789-17-P Transmission Shifter Cover Smooth Allen Screw Kit 1991-Up Harley-Davidson Dyna - Chrome Plated
$19.36

Colony #9774-8-P Oil Pump Mounting Kit Smooth Chrome Allen Harley Sportster 1991-up
$9.68

Colony #9760-4-P Lifter Base Smooth Chrome Allen Bolt Kit Harley Sportster 1995-03
1 review $8.78

Colony #9759-4-P Lifter Base Smooth Chrome Allen Screw Kit Harley Sportster 1991-94
$9.56

Colony #9752-4-P Oil Filter Adaptor Smooth Chrome Screw Kit Harley XL 1986-1990
$7.96

Colony #9748-16-P Head Bolt Smooth Chrome Allen Bolt Kit Harley Sportster 1973-85
$52.87

Colony #9747-16-P Head Bolt Smooth Chrome Allen Kit Harley Sportster 1957-72
$49.25

Colony #8918-19 Primary Cover Cap Screw Kit 1989-2006 Harley-Davidson Softail 1991-2005 Dyna - Chrome Plated
$56.11

Colony #8907-5-P Transmission Shifter Cover Speedo Sensor Kit Allen 1987-Up Harley-Davidson FX/FL/Softail - Chrome Plated
$13.02

Colony #8817-10-P Oil Pump Mounting Kit Chrome Smooth Chrome Allen Harley Sportster 1977-90
$10.79

Colony #8816-10-P Oil Pump Mounting Kit Chrome Smooth Allen Harley Sportster 1954-76
$11.53

Colony #8723-16 Handlebar Clamp Mount Kit Cap Bolts Kit 1974-Up Harley-Davidson FX/FL - Chrome Plated
$18.72

Colony #8489-8 Handlebar Switch Housing Cap Screw Kit 1973-1981 Harley-Davidson Big Twin/Sportster - Chrome Plated
$21.90

Colony #8482-20 Primary Cover Cap Screw Kit 1980-1984 Harley-Davidson 5 Speed Big Twins - Chrome Plated
$48.73

Colony #8478-27 Transmission Cap Screw and Nut Kit 1980-1985 Harley-Davidson FLT 5 Speed - Chrome Plated
$64.09

Colony #8477-12 Oil Pump Screw Kit Chrome Cap Style Harley Big Twin 1978-91
$27.51

Colony #8476-4 Dash Mounting Chrome Cap Style Kit Harley Davidson FX 1977-85
$14.74

Colony #8472-3 Sprocket Cover Chrome Cap Nut Screw Kit Harley Sportster 77-85
$13.94

Colony #8471-14 Rocker Box High Crown Chrome Cap Bolt Kit Harley Sportster 1977-85
$60.12

Colony #8468-20 Primary Cover Cap Screw Kit 1936-1969 Harley-Davidson Big Twins - Chrome Plated
$59.38

Colony #8465-16 Heat Treated Chrome Cap Style Head Bolt Kit Harley Sportster 73-85 1000cc
$57.94

Colony #8461-2 Air Cleaner Screw Set Chrome Cap Style Harley Sportster pre-1978
$11.14

Colony #8460-20 Heat Treated Chrome Cap Style Head Bolt Kit Harley Knucklehead 1940-47
$66.63

Colony #8458-2 Generator Chrome Cap Style Screw Kit Harley Sportster 1971-85
$14.74

Colony #8454-8 Cam Cover Chrome Cap Screw Kit Harley Sportster 1971-85
$28.25

Colony #8453-11 Primary Cover Cap Screw Kit 1971-1976 Harley-Davidson Sportster - Chrome Plated
$34.40

Colony #8452-12 Primary Cover Cap Screw Kit 1965-1970 Harley-Davidson Big Twins - Chrome Plated
$36.94

Colony #8450-4 Lifter Base Chrome Cap Bolt Kit Harley Sportster 57-85
$15.52

Colony #8448-14 Rocker Box High Crown Chrome Cap Bolt Kit Harley Sportster 1957-76
$61.56

Colony #8446-10 Circuit Breaker Relay Chrome Cap Screw Kit Harley Big Twins 1936-57 Knuckle Pan
$17.14

Colony #8443-2 Generator Chrome Cap Screw Set Harley Davidson 1958-69 Pan Shovel
$13.94

Colony #8439-13 Oil Pump Cap Nut / Block Off Plug Chrome Cap Nut Set Harley 1936-67
$20.70

Colony #2996-1 Spark Plug Cable Clip Front 1936-1940 Harley-Davidson OHV - CAD Plated
$5.57

Colony #2992-4 Handlebar Bolt Kit 1940-1948 Harley-Davidson Big Twin Springers 1940-Up /45 Springer - Parkerized
$9.68

Colony #2987-4 Spring Retainer Acorn Nut Set 1936-1938 Harley-Davidson Big Twin 1949-1957 45s - Parkerized
$21.18

Colony #2977-2 Generator Screws 1930-1936 Harley-Davidson VL - CAD Plated
$10.37

Colony #2976-1 Tansmission Filler Plug 1917-1929 Harley-Davidson 61" 1921-1936 74"- CAD Plated
$13.20

Colony #2974-1 Transmission Drain Plug 1911-1936 Harley-Davidson J/JD/VL - CAD Plated
$6.60

Colony #2960-1 Spark Plug Cable Clip Front 1936-1940 Harley-Davidson OHV - Parkerized
$5.57

Colony #2958-4 Hand Brake Lever Screw Kit 1928-1940 Harley-Davidson - Parkerized
$18.88

Colony #2953-5 Carburetor Support Bracket 1954-E1955 Harley-Davidson OHV Big Twins - Parkerized
$22.50

Colony #2952-6 Slotted 1/4-24 thread Nuts Pre-1930 Harley-Davidson Motor Case OEM #451-09 - Nickel Palted
$21.18

Colony #2709-24-P Upper and Lower Motor Mount Kit Smooth Allen 2009-Up Harley-Davidson FLT - Chrome Plated
$36.30

Colony #2527-8-P Rear Fender Rail Mounting Kit Smooth Allen 1980-1985 Harley-Davidson FXWG - Chrome Plated
$22.77

Colony #2400-12-P Transmission Oil Pan Smooth Allen Bolt Kit Harley-Davidson FLT 2007-up - Chrome Plated
$23.72

Colony #2345-6-P Transmission Shifter Cover Smooth Allen 2006-Up Harley-Davidson Dyna - Chrome Plated
$13.02

Colony #2344-10-P Oil Pan Mounting Kit Smooth Allen 2006-Up Harley-Davidson Dyna - Chrome Plated
$21.60

Colony #2179-7-P Windshield Mounting Kit Smooth Allen 2002-Up Harley-Davidson VRSC - Chrome Plated
$11.17

Colony #2935-1 Fork Tube Cap 1975-1976 Harley-Davidson XLH/XLCH - Chrome Plated
$24.26

Colony #7933 Complete Show Bike Kit Acorn Hardware Harley-Davidson 2007-up Twin Cam 88 Softail - Chrome Plated
$346.14

Colony #7906 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1940-1947 Knucklehead - Chrome Plated
$395.76

Colony #3076-36 Valve Cover Kit 1939-1948 Harley-Davidson UL/ULH - Chrome Plated
$269.50

Colony #3061-14 Head Bolt Kit 1929-19347 Harley-Davidson Singles - Parkerized
$85.25

Colony #3044-7 Foot Brake Lever and Bracket Mounting Kit 1936-1971 Harley-Davidson Big Twin - Parkerized
$6.38

Colony #3029-12 Pushrod Covers 1940-1947 Harley-Davidson Knucklehead - CAD Plated
$54.67

Colony #3027-20 Upper Pushrod Covers Kit 1940-1947 Harley-Davidson Knucklehead - Parkerized
$50.08

Colony #3026-12 Pushrod Covers 1940-1947 Harley-Davidson Knucklehead - Parkerized
$54.67

Colony #1004-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 1992-1999 Softail - Chrome Plated
$251.56

Colony #1004 Complete Show Bike Kit Allen Hardware Harley-Davidson 1992-1999 Softail - Chrome Plated
$211.75

Colony #9950-6-P Oil Hose Cover Mounting Kit Smooth Allen 1999-Up Harley-Davidson Twin Cam 88 Dyna/FLT - Chrome Plated
$6.38

Colony #9935-8-P Transmission to Motor Mount Kit Smooth Allen 1999-2006 Harley-Davidson Twin Cam - Chrome Plated
$14.34

Colony #9881-2 Generator Screw Kit Stock 1971-1985 Harley-Davidson Sportster - Zinc Plated
$7.51

Colony #9815-16 Lifter Base Screw Kit Special 1/4-20 Aftermarket Harley-Davidson Cases - CAD Plated
$15.79

Colony #9757-2-P Generator Smooth Allen Mounting Screws 1957-1970 Harley-Davidson Sportster - Chrome Plated
$13.55

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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