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 #7809-2 Clutch Adjusting Hole Filler Cap 1977-1985 Harley-Davidson Sportster
$36.20

Colony #7713-20 Head Bolt Set CAD Plated 1936-1939 Harley-Davidson Knucklehead - CAD Plated
$64.09

Colony #7712-36 Head Bolt Set 1940-Up Harley-Davidson 45's 1930-1947 Flathead 74's/80's with Iron Heads - CAD Plated
$97.04

Colony #7711-18 Head Bolt Set CAD Plated 1940-1947 Harley-Davidson Flathead 74's/80's with Aluminum Heads - CAD Plated
$98.48

Colony #7709-32 Head Nut & Washer Kit 1942-Up Harley-Davidson 45's with Cast Iron Heads & 3/8-16 Head Studs
$40.56

Colony #7631-11 Acorn Primary Cover Screw Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
$37.66

Colony #7630-3 Sprocket Cover Screw & Acorn Nut Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
$14.34

Colony #7629-14 High Crown Acorn Rocker Box Bolt Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
$62.27

Colony #7628-8 Lifer Base Screw Kit 1976-Up Harley-Davidson 74's - Chrome Plated
$25.71

Colony #7625-2 Handlebar End Nuts 1931-1936 Harley-Davidson Big Twin and Side Valves 1931-1939 45's
$15.73

Colony #7623-8 Hi-Torq Cylinder Base Nut Set - Chrome Plated
$32.48

Colony #7602-11 Transmission Mounting Hardware Kit 1936-1964 Harley-Davidson Big Twins - Chrome Plated
$31.28

Colony #7601-2 Clutch Adjusting Hole Cap with O-Ring 1971-1976 Harley-Davidson Sportster
$36.20

Colony #7509-20 Upper Pushrod Cover Kit 1936-1939 Harley-Davidson Knucklehead - Chrome Plated
$50.08

Colony #7414-20 Acorn Primary Cover Screw Kit 1936-1969 Harley-Davidson Big Twin With Steel Primary Cover- Chrome Plated
$60.91

Colony #7412-24 Acorn Rocker Arm Cover Screw Kit All Harley-Davidson Panheads- Chrome Plated
$60.91

Colony #7402-7 Acorn Head Timing Cover Screw Kit 1970-1992 Harley-Davidson Big Twins - Chrome Plated
$24.26

Colony #7352-16 Heat Treated Acorn Head Bolt Kit Late 1973-1985 Harley-Davidson Sportster - Chrome Plated
$57.94

Colony #7206-2 Acorn Head Air Cleaner Screw Set Pre-1978 Harley-Davidson Sportsters And 74's - Chrome Plated
$11.14

Colony #7152-20 Heat Treated Acorn Head Bolt Kit - 1936-1939 Harley-Davidson Knucklehead - Chrome Plated
$66.63

Colony #7151-16 Heat Treated Acorn Head Bolt Kit - 1957-Early 1973 Harley-Davidson Sportster - Chrome Plated
$57.94

Colony #7150-8 Acorn Head Cam Cover Screw Kit - 1971-1985 Harley-Davidson Sportster - Chrome Plated
$29.70

Colony #7149-11 Acorn Head Primary Cover Screw Kit - 1971-1976 Harley-Davidson Sportster - Chrome Plated
$36.20

Colony #7144-5 Acorn Head Screw Kit For Rear Wheel Star Shaped Covers 1/4-24 Thread - Chrome Plated
$17.22

Colony #7131-8 Lifter Base Acorn Screw Kit - 1936-1975 OHV Harley-Davidson Davidson Big Twin - Chrome Plated
$25.71

Colony #7130-2 Acorn Head Generator Screw Kit - 1957-1970 Harley-Davidson Sportster - Chrome Plated
$13.94

Colony #7120-4 Aluminum Valve Retainers - All Harley-Davidson Davidson OHV 74's
1 review $35.13

Colony #7116-14 Acorn Head Primary Cover Screw Kit - 1967-1970 Harley-Davidson XLH 1970 XLCH - Chrome Plated
$39.11

Colony #7115-2 Acorn Head Countershaft Sprocket Cover Screw Set - 1957-1969 Harley-Davidson Sportster 1952-56 K Model - Chrome Plated
$14.74

Colony #8308 CHR Complete Stock Hardware Kit - 1937-1973 Harley-Davidson 45 with Cast Iron Head - Chrome Plated
$366.55

Colony #8306 PARK Complete Stock Hardware Kit - 1940-1948 Harley-Davidson 74 & 80 Aluminum Head - CAD Plated
$339.82

Colony #8304 CHR Complete Stock Hardware Kit - 1937-1939 Harley-Davidson 74 & 80 Cast Iron Head - Chrome Plated
$389.63

Colony #8313 CAD Complete Stock Hardware Kit - 1979-1980 Harley-Davidson Shovelhead - CAD Plated
$266.32

Colony #8307 CHR Complete Stock Hardware Kit - 1966-1969 Harley-Davidson Shovelhead - Chrome Plated
$387.28

Colony #9774-8 Oil Pump Mounting Allen Screw Kit 1991-2003 Harley-Davidson Sportster - Chrome Plated
1 review $8.20

Colony #9768-15 Primary Cover Acorn Screw Kit 1991-1993 Harley-Davidson XL - Chrome Plated
$38.39

Colony #9759-4 Lifter Base Allen Screw Kit 1991-1994 Harley-Davidson Sportster - Chrome Plated
$9.16

Colony #9757-2 Generator Chrome Allen Screw Kit 1957-1970 Harley-Davidson Sportster - Chrome Plated
$12.74

Colony #9756-1 Kicker Starter Spring Stud 1941-1963 Harley-Davidson 45's - Parkerized
$7.58

Colony #9755-1 Kicker Starter Spring Stud 1941-1963 Harley-Davidson 45's - CAD Plated
$7.58

Colony #9754-1 Kicker Starter Spring Stud 1941-1963 Harley-Davidson 45's - Chrome Plated
$9.56

Colony #9752-4 Oil Filter Adaptor Allen Screw Kit 1986-1990 Harley-Davidson XL - Chrome Plated
$4.76

Colony #9749-11 Primary Cover Allen Screw Kit 1986-1990 Harley-Davidson Sportster - Chrome Plated
$20.85

Colony #9748-16 Head Bolt Allen Screw Kit 1973-1985 Harley-Davidson Sportster - Chrome Plated
$49.97

Colony #9745-7 Rear Chain Guard Mounting Kit 1936-1952 Harley-Davidson 45 Solo Pre-1973 Servicar - CAD Plated
$6.66

Colony #9743-2 Front Hub Bearing Retainer & Lock Nut 1930-Up Harley-Davidson 45 Solo - Parkerized
$17.92

Colony #9742-6 Front Fender Mounting Kit 1936-1948 Harley-Davidson Springers - Chrome Plated
$22.09

Colony #9740-2 Front Brake Cable Sleeve Adjuster 1928-1940 Harley-Davidson All Models - Chrome Plated
$17.14

Colony #9738-1 Rocker Feedline Nipple 1936-1941 Harley-Davidson OHV - Chrome Plated
$10.37

Colony #9736-1 Gear Box Adjusting Screw 1936-1964 Harley-Davidson Big Twin - CAD Plated
$15.52

Colony #9730-3 Gas Strainer Brass Cap 1932-1938 Harley-Davidson Twins
$17.52

Colony #9729-1 Gear Box Adjusting Screw 1929-Up Harley-Davidson 45's - Chrome Plated
$17.52

Colony #9719-1 Transmission Fill Plug 1941-up Harley-Davidson 45's - Parkerized
$18.72

Colony #9716-8 Cylinder Base Nut Lockwashers 1930-1977 Harley-Davidson Big Twin - Parkerized
$4.76

Colony #9715-8 Cylinder Base Nut Lockwashers 1930-1977 Harley-Davidson Big Twin - Chrome Plated
$6.14

Colony #9709-6 Clutch Arm Rebuilding Kit 1941-1943 Harley-Davidson 45 Solo 1941-1973 Servi-car - Parkerized
$25.36

Colony #9703-2 Intake Manifold Nuts 1937-1973 Harley-Davidson 45's - Parkerized
$28.97

Colony #9701-1 Rocker Feedline Nipple 1936-1941 Harley-Davidson OHV 1937-1952 45's - Parkerized
$8.78

Colony #9690-4 Front Axle Nut Kit Parkerized 1937-1952 Harley-Davidson 45 Solo - Parkerized
$6.38

Colony #9683-2 Front Brake Cable Sleeve Adjuster & Nut 1928-1940 Harley-Davidson All Models - Parkerized
$15.52

Colony #9668-19 Timing Cover Screw Kit 1937-1973 Harley-Davidson 45's - Parkerized
$25.28

Colony #9648-1 Speedometer Cable Clamp 1941-1952 Harley-Davidson 45 Solo - Parkerized
$14.85

Colony #9647-1 Speedometer Cable Clamp 1937-1952 Harley-Davidson 45 Solo 1937-1956 Servicar - Parkerized
$7.17

Colony #9643-16 Head Bolt Kit 1954-1956 Harley-Davidson KH Model - CAD Plated
$85.45

Colony #9642-16 Head Bolt Kit 1954-1956 Harley-Davidson KH Model - Chrome Plated
$107.17

Colony #9641-16 Head Bolt Kit 1952-1953 Harley-Davidson K Model - CAD Plated
$85.45

Colony #9635-4 Oil Pump Check & Relief Valve Plugs 1981-Up Harley-Davidson FL/FX - CAD Plated
$15.94

Colony #9631-1 Oil Pump Stud Nut Short 1941-1948 Harley-Davidson 74/80 SV 1941-1954 45's - Parkerized
$5.58

Colony #9616-4 Rear Stand Mounting Kit 1938-1957 Harley-Davidson Big Twins 1939-Up 45s - Chrome Plated
$22.80

Colony #9614-10 Oil Pump Mounting Kit Late 1971-1976 Harley-Davidson Sportster - Chrome Plated
$9.56

Colony #9533-2 Clutch Gear Nut 1941-Up Harley-Davidson 45 Solo/Servicar - Parkerized
$26.81

Colony #9531-13 Rear Crash Bar Mounting Kit 1936-1957 Harley-Davidson Big Twin - CAD Plated
$36.54

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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