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.

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BEST SELLING BRANDS

TOP Custom Motorcycle Parts

Colony #2063-14 Primary Cover Phillips Screw Kit 1971-1976 Harley-Davidson Sportster - Chrome Plated
$25.30

Colony #9983-3 Shifter Cam Plunger Kit 1936-1976 Harley-Davidson Big Twin 1940-1973 45s - Parkerized
$21.73

Colony #2069-5 Rear Axle Adjuster Kit 1930-1936 Harley-Davidson 74/80 Twins - CAD Plated
4 reviews $20.99

Colony #2015-6 Oversize Panhead Valve Cover Screws 1948-1965 Harley-Davidson Panhead W/Steel D Rings - Chrome Plated
$21.73

Colony #2014-6 Oversize Panhead Valve Cover Screws 1948-1965 Harley-Davidson Panhead W/Alloy D Rings - Chrome Plated
1 review $21.73

Colony #2000-6 Swing Arm End Plates/Wheel Adjuster 1991-2005 Harley-Davidson Dyna Glide - Chrome Plated
1 review $21.73

Colony #9911-1 Fork Tube Cap 1960-1977 Harley-Davidson - Chrome Plated
$20.65

Colony #2080-4 Front Brake Caliper Mounting Allen Kit 2000-2007 Harley-Davidson FX/FL - Chrome Plated
1 review $20.11

Colony #9918-8 Rocker Arm Stud Nut Kit 1948-1965 Harley-Davidson Panhead - CAD Plated
2 reviews $19.12

Colony #2088-8 Front or Rear Caliper Mounting Allen Bolts Harley-Davidson Big Twins - Chrome Plated
1 review $19.36

Colony #9879-31 Motor Case Fastener Kit 1977-1990 Harley-Davidson Sportster - CAD Plated
2 reviews $18.76

Colony #2014-6 Oversize Panhead Valve Cover Screws 1948-1965 Harley-Davidson Panhead W/Alloy D Rings - CAD Plated
$19.12

Colony #2169-15 Oil Pan Mounting Allen Screw Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$17.88

Colony #2057-2 Speedometer Drive Block Off Plug 1957-1972 Harley-Davidson Sportster - Chrome Plated
1 review $17.14

Colony #2127-11 Generator Brush Positive Terminal Screws/Fittings 1958-1969 Harley-Davidson FL/FLH 1958-1981 XL 1958-1965 Servi-Car
3 reviews $19.36

Colony #2061-8 Cam Cover Phillips Screw Kit 1971-1980 Harley-Davidson Sportster - Chrome Plated
$16.94

Colony #9973-4 1/2 inch Countersunk Washers - 4 pack - Chrome Plated
$15.94

Colony #9984-24 Valve Cover Washers 1954-1965 Harley-Davidson Panhead - Chrome Plated
$15.52

Colony #2100-16 Lifter Base Phillips Screw Kit 1950-1953 Harley-Davidson Big Twin 1952-1956 K Models - CAD Plated
$18.52

Colony #9894-12 Gas Tank Mounting Kit 1937-1952 Harley-Davidson 45 Solo 1937-Up Servi-car - Chrome Plated
$18.15

Colony #2138-4 Handlebar Riser Hex Bolt Kit 1/2-13 x 3-1/2" - Chrome Plated
1 review $14.89

Colony #2135-4 Handlebar Riser Hex Bolt Kit 1/2-13 x 2-1/2" - Chrome Plated
1 review $14.89

Colony #2134-4 Handlebar Riser Allen Bolt Kit 1/2-20 x 3" - Chrome Plated
$14.89

Colony #2130-4 Handlebar Riser Allen Bolt Kit 1/2-13 x 3-1/2" - Chrome Plated
$14.89

Colony #2129-4 Handlebar Riser Allen Bolt Kit 1/2-13 x 3" - Chrome Plated
5 reviews $14.89

Colony #9886-12 Floorboard Hinge Bolt Kit 1914-1940 Harley-Davidson All Models - Parkerized
2 reviews $14.74

Colony #2077-5 Gas Tank Mounting Acorn Kit 2000-Up Harley-Davidson Softail - Chrome Plated
2 reviews $14.83

Colony #9874-2 Oil Screen Plug 1966-1969 Harley-Davidson Big Twins - Chrome Plated
$14.34

Colony #2072-4 Gas Tank Mounting Kit Countersunk 1991-1999 Harley-Davidson Softail - Chrome Plated
$14.34

Colony #2062-8 Cam Cover Phillips Screw Kit 1971-1980 Harley-Davidson Sportster - CAD Plated
1 review $14.52

Colony #2071-10 Inner Primary Cover Chain Guard Kit 1936-1964 Harley-Davidson Big Twin - Chrome Plated
1 review $14.34

Colony #2003-6 Tool Box Mounting Kit 1958-Early 1962 Harley-Davidson Big Twin - CAD Plated
$13.92

Colony #9967-4 Top Motor Mount to Cylinder Head Hardware 1993-Up Harley-Davidson Big Twin 1986-Up XL - Zinc Plated
$12.74

Colony #9965-4 Footpeg Mounting Shoulder Bolt/Nut Kit 1952-Up Harley-Davidson FX/FL/XL - CAD Plated
$13.16

Colony #9895-12 Gas Tank Mounting Kit 1937-1952 Harley-Davidson 45 Solo 1937-Up Servi-car - CAD Plated
$15.62

Colony #2090-2 Swing Arm End Plates 19819-1994 Harley-Davidson FXR 1979-2001 FLT - Chrome Plated
3 reviews $12.74

Colony #2001-2 Swing Arm End Plates 1991-Up Harley-Davidson Dyna Glide - Chrome Plated
$12.74

Colony #9907-4 Fork Slider Drain Screws 1952-1972 Harley-Davidson K/XL/FX - Chrome Plated
$11.96

Colony #9876-2 Oil Screen Plug 1970-1980 Harley-Davidson Big Twins - Chrome Plated
$11.96

Colony #9981-8 Front Fork and Back Panel Mounting Button Allen Kit 1987-Up Harley-Davidson FLSTC/FLSTF/FLSTN
$11.90

Colony #2109-12 Rear Master Cylinder and Cover Allen Hardware Kit 1982-1994 Harley-Davidson FXR 1984-1995 Softail - Chrome Plated
$11.17

Colony #9935-8 Transmission to Motor Mount Allen Kit 1999-2006 Harley-Davidson Twin Cam/Dyna/FLT 2000-2006 Softail - Chrome Plated
$11.14

Colony #9930-14 Intake Manifold to Cylinder Head Allen Kit 1982-1989 Harley-Davidson Big Twins
$10.37

Colony #9880-2 Generator Screw Kit 1971-1985 Harley-Davidson Sportster - Chrome Plated
$10.76

Colony #9871-10 License Plate Mounting Kit Flat Head Allen Harley-Davidson - Chrome Plated
$10.76

Colony #2006-3 Headlamp Mounting Kit 1949-1959 Harley-Davidson Big Twins 1952-1958 XL/K/KH - CAD Plated
$10.76

Colony #2042-5 Rear Axle Clip 1991-Up Harley-Davidson FL/FX/XL OEM #510 - Chrome Plated
1 review $12.10

Colony #2041-7 Front Wheel Brake Cable Tube Clamp 1952-1972 Harley-Davidson KH/XL/XLH/XLCH 1971-1972 FX - CAD Plated
1 review $16.50

Colony #9898-1 Kicker Starter Spring Stud 1952-1970 Harley-Davidson Sportster - Chrome Plated
$9.56

Colony #9890-7 Front/Rear Axle Nut Kit 1952-1966 2 Cycle Harley-Davidson 125/165/175 - CAD Plated
$9.56

Colony #9962-6 Handlebar Clamp & Gauge Mount Kit 1995-Up Harley-Davidson FX/XL - Chrome Plated
$9.31

Colony #9957-2 Air Cleaner Mounting Nut 1983-Up Harley-Davidson Big Twins - Chrome Plated
$9.16

Colony #9915-4 Seat Bracket Button Head Mounting Kit 1987-Up Harley-Davidson Softail/Fat Boy - Chrome Plated
$8.93

Colony #9905-16 Floorboard Stud Mounting Kit 1936-1957 Harley-Davidson Big Twins - Parkerized
$13.75

Colony #2060-5 Sprocket Cover Screw Kit 1977-1980 Harley-Davidson Sportster - CAD Plated
$8.78

Colony #9901-1 Kicker Starter Spring Stud 1971-1987 Harley-Davidson Sportster - CAD Plated
2 reviews $7.58

Colony #9899-1 Kicker Starter Spring Stud 1952-1970 Harley-Davidson Sportster - CAD Plated
$7.58

Colony #9966-4 Footpeg Mounting Bolt/Nut Kit 1969-Up Harley-Davidson FX/FL/XL - Zinc Plated
$6.78

Colony #9906-14 Floorboard Stud Mounting Kit 1935-Up Harley-Davidson 45 and Servi-car - Parkerized
1 review $11.55

Colony #9964-2 Fork Tube Bolt Washers 1978-Up Harley-Davidson FL/FXWG/Softail - Chrome Plated
2 reviews $5.18

Colony #9939-6 Oil Filter Adapter Mounting Allen Kit 1999-Up Harley-Davidson Twin Cam Dyna/FLT - Chrome Plated
$4.76

Colony #9916-2 Custom Air Cleaner Cover Countersunk Mounting Kit 1983-Up Harley-Davidson Big Twins - Chrome Plated
$4.76

Colony #9909-2 Fork Slider Drain Screws 1949-E1977 Harley-Davidson FL - Chrome Plated
$3.99

Colony #2007-6 Air Cleaner Mounting Allen Screw Kit 1978-1983 Harley-Davidson Big Twin - Chrome Plated
$4.09

Lowbrow Customs WX Split Gas Tanks - Bolt-On for 1936 - 1984 Big Twin Harley-Davidsons - 2.25 gallon
84 reviews $399.99

Lowbrow Customs Tsunami Fender - Raw Aluminum - 2004 and Up Sportsters
23 reviews $246.06

Colony #9870-16 Inner Primary Mounting Kit 1986-1993 Harley-Davidson Softail 1991-1993 Dyna Glide
1 review $24.00

Colony #9811-3 Ribbed Rear Axle Spacer Kit 1991-1999 Harley-Davidson Dyna Glide - Chrome Plated
$33.31

Colony #9809-4 Ribbed Rear Axle Nut & Spacer Kit 1984-1999 Harley-Davidson Softail - Chrome Plated
1 review $60.83

Colony #9808-6 Oil Nipple Cap 1915-1964 Harley-Davidson All Models - CAD Plated
1 review $14.85

Colony #9659-1 Gas Strainer Assembly 1932-1938 Harley-Davidson Twins - Nickle Plated
1 review $79.66

Colony #9640-16 Head Bolt Kit 1952-1953 Harley-Davidson K Model - Chrome Plated
$107.17

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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