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 #9008-5 Spark Cable Clamp 1938-1948 Harley-Davidson Side Valve Big Twin - Parkerized
$14.30

Colony #8772-2 Timing Cover Oil Passage Bolt 1963-1969 Harley-Davidson Big Twin OEM #25218-63 - CAD Plated
$11.96

Colony #8710-8 Lifter Base Screw Kit 1976-Up Harley-Davidson Big Twin - Black
$14.34

Colony #8709-8 Lifter Base Screw Kit 1976-Up Harley-Davidson Big Twin - CAD Plated
1 review $14.34

Colony #9007-2 Throttle & Spark Cable Clamp 1930-Up Harley-Davidson 45's - Parkerized
1 review $14.30

Colony #9014-3 Dash Mounting Kit Acorn 1986-Up Harley-Davidson FXR - Chrome Plated
$10.76

Colony #8885-2 Sprocket Cover Screws 1954-1970 Harley-Davidson XL - CAD Plated
$11.14

Colony #8813-4 Fork Slider Bottom Cap Stud & Nut 1949-1977 Harley-Davidson FLH Wideglide - Chrome Plated
$11.14

Colony #8610-1 Timing Plug 1931-1938 Harley-Davidson 5/8-18 Thread OEM #2326-26 - Chrome Plated
$11.14

Colony #8819-4 Clutch & Brake Lever Pivot Screw Kit 1941-1964 Harley-Davidson Big Twin/45s - CAD Plated
1 review $12.10

Colony #8816-10 Oil Pump Mounting Allen Kit 1954-1976 Harley-Davidson Sportster - Chrome Plated
$10.42

Colony #8787-2 Generator Allen Screw Kit 1971-1985 Harley-Davidson Sportster - Chrome Plated
1 review $10.76

Colony #8817-10 Oil Pump Mounting Allen Kit 1977-1990 Harley-Davidson Sportster - Chrome Plated
$9.68

Colony #8786-5 Sprocket Cover Allen Screw Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
$9.68

Colony #8757-8 Fork Bracket Cover Allen Screw Kit 1952-Up Harley-Davidson XL 1971-Up FX - Chrome Plated
$9.96

Colony #8488-10 Cylinder Head Bolt Washers 1948-Up Harley-Davidson OEM #6469 - Chrome Plated
$9.96

Colony #8401-8 Rocker Shaft Cap Nut & Washer Kit 1966-1985 Harley-Davidson Shovelhead 1957-1985 Sportster - CAD Plated
1 review $9.96

Colony #8878-2 Generator Screw Kit 1952-1970 Harley-Davidson K/XL - CAD Plated
$9.16

Colony #8795-4 Handlebar Clamp Allen Screw Kit 1974-1984 Harley-Davidson FX/XL L1977-1984 FL - Chrome Plated
1 review $9.31

Colony #8782-4 Lifter Base Allen Screw Kit 1957-1990 Harley-Davidson Sportster - Chrome Plated
$8.78

Colony #8775-4 Dash Mounting Kit Button Allen 1977-1985 Harley-Davidson FX - Chrome Plated
$9.16

Colony #8630-1 Rocker Feedline Nipple 1936-1941 Harley-Davidson OHV 1937-1952 45's Vent Line - CAD Plated
1 review $8.78

Colony #8612-1 Timing Plug 1931-1938 Harley-Davidson 5/8-18 Thread OEM #2326-26 - Parkerized
$11.55

Colony #8611-1 Timing Plug 1931-1938 Harley-Davidson 5/8-18 Thread OEM #2326-26 - CAD Plated
2 reviews $11.55

Colony #9013-4 Linkert Carb Support Bracket 1936-1952 Harley-Davidson OEM #27432-36 - Parkerized
$12.65

Colony #8854-4 Front Axle Nut Kit 1937-1952 Harley-Davidson 45 Solo OEM #3910-37 - Chrome Plated
$8.36

Colony #8784-4 Sprocket Cover Allen Screw Kit 1971-1976 Harley-Davidson Sportster - Chrome Plated
$7.45

Colony #8889-2 Sprocket Cover Screws 1971-1976 Harley-Davidson XL - CAD Plated
$7.17

Colony #8718-4 Cap Head Headlight Visor Mounting Bolt 1959-Up Harley-Davidson XL/FX/FXR - Chrome Plated
$7.17

Colony #8717-4 Acorn Head Headlight Visor Mounting Bolt 1959-Up Harley-Davidson XL/FX/FXR - Chrome Plated
$7.17

Colony #8874-2 Seat Post Rod Lock Nut & Lockwasher 1925-1981 All Harley-Davidson Models (Except FX/XL) - CAD Plated
3 reviews $9.35

Colony #8797-4 Handlebar Lever Mount Allen Screw Pre-1972 Harley-Davidson FX/FL/XL - Chrome Plated
$5.96

Colony #8790-28 Rocker Box Allen Screw Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
1 review $35.87

Colony #8776-2 Clutch Adjusting Hole Filler Cap 1985-1990 Harley-Davidson XLH - Chrome Plated
$36.20

Colony #8735-24 Valve Cover Screws 45/64 inch Long 1954-1965 Harley-Davidson Panhead With Steel D-Rings - CAD Plated
1 review $34.93

Colony #8733-24 Valve Cover Screws 1-1/4 inch Long 1954-1965 Harley-Davidson Panhead With Alloy D-Rings - CAD Plated
$34.93

Colony #8620-17 Motor Case Kit 1940-1973 Harley-Davidson 45's - CAD Plated
$35.42

Colony #8876-5 Seat Bar Bushing Set 1965-1980 Harley-Davidson Big Twin - CAD Plated
1 review $33.31

Colony #8875-5 Seat Bar Bushing Set 1937-1964 Harley-Davidson Big Twin 1929-1973 45 Solo/Servi-Car - CAD Plated
$33.31

Colony #8614-4 Rocker Shaft End Caps 1971-Up Harley-Davidson Shovelhead 1971-1984 XL - Chrome Plated
$33.31

Colony #8223-8 Rocker Shaft End Plug & Cap Kit 1966-1970 Harley-Davidson Shovelhead 1957-1970 XL - CAD Plated
1 review $31.81

Colony #8858-8 Cylinder Base Stud Set 1954-1985 Harley-Davidson K/XL OEM #16830-54 & 16830-72
2 reviews $30.42

Colony #8835-10 Sprocket Bolt & Washer Kit Allen Head 1993-1998 Harley-Davidson Big Twin Spoke Wheel 1979-1990 XL Cast Wheel - Chrome Plated
1 review $30.79

Colony #8821-18 Top of Tank Screw & Washer Kit 1918-1936 All Harley-Davidson 1936-1952 45s - Nickel Plated
$31.14

Colony #8622-16 Sprocket Cover Stud Kit 1935-1973 Harley-Davidson 45's - CAD Plated
2 reviews $30.78

Colony #8822-18-OS Oversize Top of Tank Screw & Washer Kit 1918-1936 All Harley-Davidson 1936-1952 45s - CAD Plated
$30.04

Colony #8822-18 Top of Tank Screw & Washer Kit 1918-1936 All Harley-Davidson 1936-1952 45s - CAD Plated
$30.04

Colony #8750-14 Transmission Top Cover Allen Screw 1936-1964 Harley-Davidson Big Twin - Chrome Plated
$28.97

Colony #8881-18 Rear Fender Support Mounting Kit 1959-1981 Harley-Davidson XL - Chrome Plated
3 reviews $27.89

Colony #8880-18 Rear Fender Support Mounting Kit 1952-1958 Harley-Davidson K/XL - Chrome Plated
$27.89

Colony #8490-8 Lifter Base Acorn Head Screw Kit Harley-Davidson Late Shovelhead Lifter to 1/4-24 Motor Case - Chrome Plated
$27.51

Colony #8845-2 Shift Gate Clamp Nut 1916-1935 Harley-Davidson 1936 VL - Nickel Plated
$26.81

Colony #8842-10 Sprocket Allen Bolt & Nut Kit 1985-1992 Harley-Davidson Big Twin - Chrome Plated
$26.40

Colony #8707-6 Tappet Oil Screen/Oil Pump Check Valve/Relief Valve Plug Set 1981-Up Harley-Davidson Big Twin OEM #26263-80 - Chrome Plated
4 reviews $26.07

Colony #9002-4 Evo Cap Head Bolt Covers 1984-1985 Harley-Davidson FL/FX/XL - Chrome Plated
1 review $25.71

Colony #9000-4 Evo Acorn Head Bolt Covers 1984-1985 Harley-Davidson FL/FX/X - Chrome Plated
1 review $25.71

Colony #8936-3 Pivot Bolt Washer & Spacer 1973-1978 Harley-Davidson XL - Chrome Plated
3 reviews $25.71

Colony #8904-6 Clutch Arm Rebuilding Kit 1941-1943 Harley-Davidson 45 Solo 1941-1973 Servi-Car - CAD Plated
$25.36

Colony #8868-16 Rocker Box Screw Kit Acorn Head 1985-Up Harley-Davidson FL/FX/XL - Chrome Plated
2 reviews $25.72

Colony #8755-12 Timing Cover Screw Kit 1936-1969 Harley-Davidson Big Twin - Chrome Plated
2 reviews $24.62

Colony #8010-10 Front Brake Shackle Rebuilding Kit 1940-1948 Harley-Davidson Big Twins & 45's
$90.88

Colony #7711-18-45 Head Bolt Set 1940-1954 Harley-Davidson 45's with Aluminum Heads - CAD Plated
$88.72

Colony #7157-20 Heat Treated Acorn Head Bolt Kit - 1940-1947 Harley-Davidson Knucklehead - Chrome Plated
$66.63

Colony #7714-20 Head Bolt Set CAD Plated 1940-1947 Harley-Davidson Knucklehead Engines - CAD Plated
$64.09

Colony #7136-14 High Crown Acorn Rocker Box Bolt Kit - 1957-1976 Harley-Davidson Sportster - Chrome Plated
1 review $61.56

Colony #7134-8 Custom Aluminum Pushrod Covers - 1957-1979 Harley-Davidson Sportster - Chrome Plated
5 reviews $80.00

Colony #7133-8 Stock Aluminum Pushrod Covers - 1936-1939 Harley-Davidson Knucklehead - Chrome Plated
$80.00

Colony #8777-20 Head Bolt Allen Screw Kit 1948-Up Harley-Davidson Panhead/Shovelhead - Chrome Plated
$57.94

Colony #7822-12 Pushrod Covers 1957-E1979 Harley-Davidson Sportster - Chrome Plated
2 reviews $57.94

Colony #7517-8 Knucklehead Rocker Arm Cover Nut Strip & Screw Plate Kit 1936-1947 Harley-Davidson Knucklehead
1 review $57.94

Colony #8164-19 Upper And Lower Motor Mount Kit 1936-1969 Harley-Davidson Big Twin OHV - Chrome Plated
5 reviews $57.53

Colony #7824-12 Pushrod Covers 1940-1947 Harley-Davidson Knuckleheads - Chrome Plated
$54.67

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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