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 #8910-5 Transmission Shifter Cover Acorn Head Screw Kit 1980-1987 Harley-Davidson FX/FL - Chrome Plated
$17.52

Colony #8909-13 Transmission Side Cover Allen Head 1987-2006 Harley-Davidson FX/FL/Softail 1991-2005 Dyna - Chrome Plated
$28.42

Colony #8908-15 Transmission Side Cover Allen Head Screw Kit 1980-1986 Harley-Davidson FX/FL - Chrome Plated
$25.72

Colony #8907-5 Transmission Shifter Cover Allen Head Screw Kit 1988-1997 Harley-Davidson FXR/FLT/Softail - Chrome Plated
$10.42

Colony #8906-5 Transmission Shifter Cover Allen Head Screw Kit 1980-1987 Harley-Davidson FX/FL - Chrome Plated
$9.31

Colony #8903-6 Clutch Arm Rebuilding Kit 1941-1943 Harley-Davidson 45 Solo 1941-1973 Servi-Car - Chrome Plated
$27.15

Colony #8893-12 Primary Cover Screw Kit 1967-1970 Harley-Davidson XLH 1970 XLCH - CAD Plated
$20.47

Colony #8892-12 Primary Cover Screw Kit 1967-1970 Harley-Davidson XLH 1970 XLCH - Chrome Plated
$23.01

Colony #8890-20 Primary Cover Screw Kit 1957-1969 Harley-Davidson XLCH - Chrome Plated
$20.31

Colony #8882-2 Sprocket Cover Screws 1952-1953 Harley-Davidson K Model - Chrome Plated
$16.34

Colony #7110-8 Knuckle Nut Set With O-ring Seal - 1936-1947 Harley-Davidson Knucklehead - Chrome Plated
$47.80

Colony #7109-2 Crank Pin Nut - 1937-1948 Harley-Davidson 74's/80's 1936-52 61 OHV
$20.90

Colony #7103-2 Intake Manifold Nuts - 1940-1954 Overhead Valve Harley-Davidson 74's 1953-56 K/KH - Chrome Plated
$37.66

Colony #7100-13 Oil Pump Acorn Nut & Block Off Plug Set - 1936-1967 Harley-Davidson Davidson 74's - Chrome Plated
$20.31

Colony #2068-10 Allen Screw Motor Case Kit - 1977-1990 Harley-Davidson Sportster - Chrome Plated
$31.35

Colony #3653-3 Primary Inspection Cover Kit - Black Powdercoat - 1929-1952 Harley-Davidson 45's 1932-1973 Servi-car 1930-1936 VL
$22.50

Colony #3652-3 Primary Inspection Cover Kit 1929-1952 Harley-Davidson 45's 1932-1973 Servi-car 1930-1936 VL - Parkerized
$20.35

Colony #3649-1 Jiffy Stand Spring Plate 1930-1952 Harley-Davidson 45 Twins 1930-1934 Singles - CAD Plated
$16.50

Colony #3631-6 Front Stand Spring Kit 1931-1948 Harley-Davidson Big Twins - Parkerized
$11.55

Colony #3628-2 Speedo Drive Unit Retainer 1937-1952 Harley-Davidson WL - CAD Plated
$7.43

Colony #3627-2 Speedo Drive Unit Retainer 1937-1952 Harley-Davidson WL - Chrome Plated
$8.25

Colony #3625-6 Axle Cross Shaft Bracket Lockwasher Kit 1937-1950 Harley-Davidson Servi-Cars - Parkerized
$23.00

Colony #3622-1 Oil Pump Feed Line Nut 1938-1957 Harley-Davidson Big Twins - CAD Plated
$7.70

Colony #3460-5 Chain Tensioner Plate/Pad Mounting Kit 1965-1982 Harley-Davidson FL/FX/FXR - Parkerized
$14.85

Colony #3593-2 Shifter Fork Bushing Lockwashers 1935-1973 Harley-Davidson 45 Twins - Parkerized
$8.47

Colony #3613-1 Horn Bracket Spring Plate 1942-1954 Harley-Davidson All Models
$8.80

Colony #3611-2 Horn Bracket Spring Plate 1936-1941 Harley-Davidson All Models
$12.10

Colony #3610-2 Horn Bracket Spring Plate 1936-1941 Harley-Davidson All Models
$14.85

Colony #3615-1 Horn Bracket Reinforcement 1936-1948 Harley-Davidson Big Twins 1940-1957 45's
$14.85

Colony #3614-2 Horn Bracket Lockwasher 1949-1954 Harley-Davidson All Models
$14.85

Colony #3604-52 Horn Mounting Kit 1931-1936 Harley-Davidson VL 1931-1939 RL
$135.00

Colony #3606-15 Horn Mounting Kit 1942-1945 Harley-Davidson All Models
$18.70

Colony #8318 Stock Hardware Kit Late 1930-1936 Harley-Davidson VL - Parkerized
$302.50

Colony #8323 Stock Hardware Kit Early 1930 Harley-Davidson VL - Parkerized
$302.50

Colony #3676-10 Knurled Allen Sprocket Bolts 2000-2006 Harley-Davidson Softail 2000-2005 Dyna - Chrome Plated
$25.97

Colony #3672-10 Knurled Allen Sprocket Bolts 1985-1992 Harley-Davidson Big Twin - Chrome Plated
$20.63

Colony #3331-1 Stem Crown Nut 1940-1957 Harley-Davidson 45 Solo and Servi-cars - Chrome Plated
$60.55

Colony #3092-24 Valve Spring Cover Kit 1937-1938 Harley-Davidson Big Twin Side Valve - Chrome Plated
$231.00

Colony #3091-24 Valve Spring Cover Kit 1930-1936 Harley-Davidson VL - Chrome Plated
$231.00

Colony #2899-2 Tool Box Strap Mounting Kit 1940-1945 Harley-Davidson Military Big Twins - Parkerized
$12.10

Colony #2165-100 5/16 inch (8mm) Allen Head Bolt Hole Plugs - 100 pack - Chrome Plated
1 review $57.20

Colony #7936 Complete Show Bike Kit Acorn Hardware 2017-Up Harley-Davidson Touring Models - Chrome Plated
$331.25

Colony #1028 Complete Show Bike Kit Knurled Allen 2017-Up Harley-Davidson Touring Models - Chrome Plated
$200.45

Colony #1027 Complete Show Bike Kit Knurled Allen 2007-Up Harley-Davidson VRSC - Chrome Plated
$112.28

Colony #3691-15 Plain Head Lower Motor Mount Kit 1937-1947 Harley-Davidson Side Valve Big Twins - Parkerized
$39.88

Colony #3689-15 Lower Motor Mount Kit 1937-1947 Harley-Davidson Side Valve Big Twins - CAD Plated
$39.88

Colony #3688-15 Lower Motor Mount Kit 1937-1947 Harley-Davidson Side Valve Big Twins - Chrome Plated
$43.45

Colony #3684-12 Lower Motor Mount Kit 1966-1969 Harley-Davidson OHV Big Twins - Parkerized
$33.00

Colony #3677-10 Sprocket Allen Bolt Kit 2007-Up Harley-Davidson Softail 2006-Up Dyna - Chrome Plated
$26.39

Colony #3570-10 Front Disc Brake Rotor Allen Screw Set 1978-1983 Harley-Davidson FXWG - Zinc Plated
$11.20

Colony #3551-4 Triple Clamp Bolt 1930-1931 Harley-Davidson Twins - Parkerized
$35.20

Colony #3550-5 Shifter Gear Retaining Springs 1938-1973 Harley-Davidson 45
$12.10

Colony #3480-1 Oil Feed Line Elbow Late 1962-1965 Harley-Davidson XLCH - CAD Plated
$27.50

Colony #3541-4 Windshield Apron Coil Clips and Screw Kit 1941-1948 Harley-Davidson Winshields - Parkerized
$13.01

Colony #3517-2 Front Brake Lever Clevis Pin 1952-1972 Harley-Davidson K/KH/XL 1971-1972 FX 1951-1957 Servi-car - Parkerized
$7.57

Colony #3079-3 Sidecar Body Connector Stud Kit 1958-1972 Harley-Davidson Sidecars - Parkerized
$34.38

Colony #3450-6 Leg Shield U-bolt Mounting Kit 1948-E1951 Harley-Davidson Big Twins - Parkerized
$26.40

Colony #3437-1 Brake Cross Over Shaft Lever - Left End - 1939-1957 Harley-Davidson Sidecars - Parkerized
$38.50

Colony #3528-2 Manifold Intake Nipple Brass Seals 1923-1924 Harley-Davidson DCA/DCB 1925-1929 74" 1928-29 61"
$7.87

Colony #3527-8 Sidecar Frame Lower Clamp Bolt 1936-1972 Sidecars - Parkerized
$24.19

Colony #3526-2 Brass Intake Manifold Seals fits 1917-1923 Harley-Davidson 61"
$7.26

Colony #3510-2 Manifold Intake Nuts 1915-1927 Harley-Davidson 61" 1921-1924 FD/JD - Nickel Plated
$29.70

Colony #3509-2 Manifold Intake Nipples 1917-23 Harley-Davidson 61" Motor - Nickel Plated
$47.30

Colony #3507-2 Crankcase Relief Plug Harley-Davidson WLA - Parkerized
$12.10

Colony #3504-2 Manifold Intake Nuts 1923-1924 Harley-Davidson DCA/DCB 1925-19-29 74" 1928-1929 61" L - Nickel Plated
$30.80

Colony #3503-2 Manifold Intake Nipples 1923-1924 Harley-Davidson DCA/DCB 1925-19-29 74" 1928-1929 61" L - Nickel Plated
$49.50

Colony #3495-1 Rear Support Rod Nut Kit 1930-1935 Harley-Davidson VL - Parkerized
$24.20

Colony #3488-8 Brake Lever Connecting Links Kit 1930-1957 Harley-Davidson Sidecars - Parkerized
$31.90

Colony #3485-1 Brake Operating Shaft Lever - Right Hand - 1936-1957 Harley-Davidson Sidecars - Parkerized
$27.50

Colony #3484-4 Front Brake Cable Adjuster 1955-1972 Harley-Davidson KH Sportster - CAD Plated
$22.00

Colony #3483-3 Front Brake Cable Adjuster 1952-1954 Harley-Davidson K/KH - CAD Plated
$22.00

Colony #3471-3 Foot Brake Lever Stud 1923-1929 Harley-Davidson 61" and 74" Twins - Parkerized
$20.90

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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