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 #2150-5 Rear Axle Nut Spacer Kit Smooth 2000-2001 Harley-Davidson FLT - Chrome Plated
$40.61

Colony #2148-8 Pushrod Cover Kit for Harley-Davidson Twin Cam Motors - Chrome Plated
$77.15

Colony #2145-1 Primary Cover Filler Plug 1954-1970 Harley-Davidson Sportster - Chrome Plated
$27.07

Colony #2118-15 Lower Front Hex Head Motor Mount Kit 2000-Up Harley-Davidson Softail - Zinc Plated
$44.67

Colony #2102-12 Timing Cover Phillips Screw Kit 1950-1952 Harley-Davidson Big Twin - CAD Plated
$21.78

Colony #2101-12 Timing Cover Phillips Screw Kit 1950-1952 Harley-Davidson Big Twin - Chrome Plated
$24.20

Colony #2098-2 Generator Phillips Screw Kit 1950-1954 Harley-Davidson Big Twin - CAD Plated
$8.47

Colony #2097-2 Generator Phillips Screw Kit 1950-1954 Harley-Davidson Big Twin - Chrome Plated
$11.40

Colony #2092-12 Housing to Frame Clamp Bolt Kit 1932-1941 Harley-Davidson Servi-car - Parkerized
$28.42

Colony #2089-8 Springer Spring Rod Kit 1930 Harley-Davidson VL OEM #2623-23
$59.55

Colony #2059-5 Sprocket Cover Screw Kit 1977-1980 Harley-Davidson Sportster - Chrome Plated
$10.89

Colony #2058-1 Fork Stem Cap 1980-Up Harley-Davidson FXST/FXWG - Chrome Plated
$15.27

Colony #2056-1 Head Bolt 1965-1973 Harley-Davidson 45's - CAD Plated
$8.36

Colony #2055-1 Head Bolt 1965-1973 Harley-Davidson 45's - Chrome Plated
$9.56

Colony #2049-18 Jiffy Stand/Shift Lever/Footrest Hardware 2000-Up Harley-Davidson Softail - Chrome Plated
$24.62

Colony #2047-4 Voltage Regulator Mounting Acorn Kit 2000-Up Harley-Davidson Softail - Chrome Plated
$11.96

Colony #2043-26 Fender Strut Mounting Low Profile Allen Kit 2000-2003 Harley-Davidson FLST 2000-2002 FXST - Chrome Plated

$62.27

Colony #2035-5 Front Axle Nut Grooved Spacer Kit 2000-2006 Harley-Davidson FLT - Chrome Plated
$46.35

Colony #2033-4 Front Axle Nut Grooved Spacer Kit 2000-2006 Harley-Davidson FLSTC - Chrome Plated
$33.31

Colony #2032-4 Front Axle Nut Smooth Spacer Kit 2000-Up Harley-Davidson FXSTS - Chrome Plated
$31.87

Colony #2031-4 Front Axle Nut Grooved Spacer Kit 2000-Up Harley-Davidson FXSTS - Chrome Plated
$33.31

Colony #2030-5 Front Axle Nut Smooth Spacer Kit 2000-2006 Harley-Davidson FLSTF/FLSTF - Chrome Plated
$43.45

Colony #2029-5 Front Axle Nut Grooved Spacer Kit 2000-2006 Harley-Davidson FLSTF/FLSTF - Chrome Plated
$46.35

Colony #2021-5 Front Axle Nut Grooved Spacers 2000-2005 Harley-Davidson FXST/FXSTB/FXDWG - Chrome Plated
$46.35

Colony #2019-8 Rocker Shaft End Plug 1957-1970 Harley-Davidson Big Twin - Chrome Plated
$43.45

Colony #2017-8 Head Bolt Washers 1984-Early 1985 Harley-Davidson Big Twin/XL - Chrome Plated
$34.76

Colony #2010-10 Cylinder Head Bolt Washers 1940-1946 Harley-Davidson WLD - Parkerized
$7.26

Colony #2004-6 Tool Box Mounting Kit Late 1962-1964 Harley-Davidson Big Twin - CAD Plated
$20.57

Colony #9806-8 Oil Pump Mounting Bolt Kit Acorn Nut 1977-1990 Harley-Davidson Sportster - Chrome Plated
$15.14

Colony #9805-10 Oil Pump Mounting Nut Allen Screw Kit 1954-1976 Harley-Davidson Sportster - Chrome Plated
$19.12

Colony #9852-5 Primary Cover Screw Kit 1952-1956 Harley-Davidson K Model - Chrome Plated
$17.14

Colony #9850-5 Primary Cover Screw Kit 1957-1966 Harley-Davidson XL/XLH - Chrome Plated
$17.14

Colony #9844-5 Chrome Countersink Washer Set for 7/16" Flat Head Socket Harley-Davidson - Chrome Plated
$19.93

Colony #9828-16 Lifter Base Screw Kit 1/4-20 Oval Allen Harley-Davidson After Market Cases- Chrome Plated
$17.92

Colony #9825-4 Custom Ribbed Front Axle Nut & Spacer Kit 1984-1996 Harley-Davidson FXST/FXSTC/FXSTB 1984-1994 FXDWG/FLT - Chrome Plated
$33.31

Colony #9823-3 Custom Ribbed Front Axle Nut & Spacer Kit 1988-1996 Harley-Davidson FXSTS - Chrome Plated
$33.31

Colony #9822-4 Oil Filter Adaptor Mounting Acorn Kit 1992-Up Harley-Davidson Big Twin - Chrome Plated
$7.96

Colony #9820-6 Timing Cover Acorn Screw Kit 1993-Up Harley-Davidson Big Twin - Chrome Plated
$23.54

Colony #9816-16 Lifter Base Screw Kit 1/4-20 Harley-Davidson Aftermarket Cases - Parkerized
$15.79

Colony #9801-14 Front & Rear Support Rod Mounting Kit 1932-1973 Harley-Davidson 45's - CAD Plated
$32.23

Colony #9800-14 Front & Rear Support Rod Mounting Kit 1932-1973 Harley-Davidson 45's - Chrome Plated
$42.74

Colony #9791-15 Rear Fender Mounting Kit 1929-1952 Harley-Davidson 45 Solo - CAD Plated
$47.95

Colony #9785-9 Transmission Shifter Cover Acorn 1991-Up Harley-Davidson Dyna - Chrome Plated
$22.09

Colony #9777-8 Handlebar Lever Mount & Master Cylinder Acorn Screw Kit 1982-1995 Harley-Davidson Big Twin/XL - Chrome Plated
$20.27

Colony #9775-8 Oil Pump Mounting Kit Acorn Nut 1991-Up Harley-Davidson Sportster - Chrome Plated
$15.14

Colony #9765-4 Lifter Base Acorn Screw Kit 1991-1994 Harley-Davidson Sportster - Chrome Plated
$15.14

Colony #9764-16 Oil Pump Mounting Kit Cap Style 1992-Up Harley-Davidson Big Twin - Chrome Plated
$28.97

Colony #9763-16 Oil Pump Mounting Kit Acorn 1992-Up Harley-Davidson Big Twin - Chrome Plated
$28.97

Colony #2561-2 Panel Switch Knob and Screw Kit L1943-1946 Harley-Davidson Big Twin & 45s - Parkerized
$13.20

Colony #2554-34 Machine Gun Bracket and Ammo Box Mounting Kit 1940-1942 Harley-Davidson WLA
1 review $123.97

Colony #2547-1 Wire Clip Frame Bull Neck Head Tube 1945-E1947 Harley-Davidson - CAD Plated
$16.50

Colony #2545-1 Wire Clip Frame Head Tube 1947-1978 Harley-Davidson Big Twins - CAD Pated
$16.50

Colony #2542-10 Circuit Breaker to Coil Wire Assembly 1936-1948 Harley-Davidson Twins
$24.20

Colony #2539-1 Sprocket Shaft and Gear Shaft Nut 1930-1936 Harley-Davidson VL
$11.00

Colony #2534-19 Primary Cover Acorn Mounting Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$49.34

Colony #2533-6 Transmission Shifter Cover Acorn Mounting Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$20.88

Colony #2532-14 Transmission Side Cover Acorn Mounting Screw Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$40.48

Colony #2509-6 Front Axle Nut Spacers Washer Kit 2008-Up Harley-Davidson Sportster - Chrome Plated
$43.45

Colony #2500-1 Pike Nut Fork Tube Plug 1985-Up Harley-Davidson Sportster & Superglide - Chrome Plated
$35.42

Colony #2499-1 Pike Nut Fork Tube Plug 1952-1972 Harley-Davidson XL/K 1971-1972 Superglide - Chrome Plated
$31.63

Colony #2492-1 Wire Clip Tail Light 1923-1933 Harley-Davidson All Models - Parkerized
$16.50

Colony #2486-1 Pike Nut Tappet Oil Screen Oil Pump Check Valve Plug 1981-Up Harley-Davidson Big Twins - Chrome Plated
$13.92

Colony #2485-22 Motor Mounting Kit Upper and Lower Hex 2007-Up Harley-Davidson - Chrome Plated
$50.60

Colony #2484-3 Foot Clutch Lever Pin Rebuild Kit 1938-1940 Harley-Davidson Big Twins 1938-1952 45s
$13.92

Colony #2482-3 Foot Clutch Lever Pin Rebuild Kit 1941-1964 Harley-Davidson Hand Shifts
$13.92

Colony #2480-4 Shifter Rod End Bolt and Bushing Kit 1930-1936 Harley-Davidson VL - CAD Pated
$13.92

Colony #2478-2 Control Coil Adjusting Sleeve 1929-1933 Harley-Davidson DR/RL/VL - Parkerized
$13.92

Colony #2475-19 Transmission Side Cover Acorn Screw Kit 2007-Up Harley-Davidson Softail - Chrome Plated
$53.13

Colony #2473-6 Transmission Side Cover Acorn Screw Kit 2007-Up Harley-Davidson Softail - Chrome Plated
$20.88

Colony #2472-12 Transmission Shifter Cover Allen Screw Kit 2007-Up Harley-Davidson Softail - Chrome Plated
$9.05

Colony #2471-20 Primary Cover Mounting Allen Screw Kit 2007-Up Harley-Davidson Softail - Chrome Plated
$53.13

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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