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 #7610-4 Rocker Stud Bushing Set 1930-1948 Harley-Davidson Big Twin Springers
1 review $48.88

Colony #7350-15 Acorn Primary Cover Screw Kit 1971-Up & All 4 Speed Harley-Davidson Big Twins - Chrome Plated
$48.73

Colony #8011-4 Rocker Stud Bushing Kit 1930-1952 Harley-Davidson 45 Solo
$48.52

Colony #7706-2 Springer Spring Rod Bushings Harley-Davidson 45's And 1931-1945 Big Twin Springers
2 reviews $43.82

Colony #7410-1-US Sprocket Shaft Bearing Retainer with Lip Seal -.002 Undersized Threads 1955-1968 Harley-Davidson 74's
1 review $45.98

Colony #7410-1-OS Sprocket Shaft Bearing Retainer with Lip Seal +.002 Oversized Threads 1955-1968 Harley-Davidson 74's
$45.98

Colony #7707-4 Spring Rod Kit 1936-1947 Harley-Davidson 45's & Big Twin Springers
2 reviews $42.63

Colony #7700-3 Fork Tube Spring Retainers And Pin Wrench Kit 1952-1972 Harley-Davidson Sportster
$42.00

Colony #8202-18 Rear Fender Mounting Kit 1936-1957 Harley-Davidson Big Twins - CAD Plated
$42.00

Colony #7627-4 Weld-In Aluminum Intake Manifold Nipples 1948-1954 Harley-Davidson Panhead
$36.94

Colony #7600-4 Primary Cover Filler Cap/Breather With O-ring 1954-1976 Harley-Davidson Sportster - Chrome Plated
$36.94

Colony #8005-12 Electrical Terminal Box Assembly1948-1969 Harley-Davidson Big Twins & 45's
2 reviews $55.04

Colony #7519-4 Aluminum Alloy Tubular Pushrods 1948-1952 61c.i. Harley-Davidson Panhead
$55.00

Colony #7506-4 Aluminum Alloy Tubular Pushrods 1948-1952 Harley-Davidson Panhead using 1966-Up Shovel Top End
1 review $55.00

Colony #7505-4 Aluminum Alloy Tubular Pushrods 1941-1947 Harley-Davidson 74 Knucklehead
$55.00

Colony #7146-12 Acorn Head Primary Cover Screw Kit - 1965-1970 Harley-Davidson 74's - Chrome Plated
3 reviews $36.20

Colony #7143-4 Knucklehead Type Rocker Arm Shaft End Plug - 1966-1970 Harley-Davidson Shovelhead 1957-70 Sportster - Chrome Plated
2 reviews $34.85

Colony #7129-12 Acorn Head Timing Cover Set - 1936-1969 Harley-Davidson 74's/61 OHV - Chrome Plated
$36.20

Colony #7710-18 Head Bolt Washer Kit 1940-1947 Harley-Davidson 45's/75's/80's with Aluminum Heads - CAD Plated
1 review $33.31

Colony #7808-4 Upper Pushrod Covers (Inner) 1957-1985 Harley-Davidson Sportster 1936-Early 1979 OHV Big Twins
3 reviews $34.05

Colony #7622-1 Fork Tube Bolt 1973-Mid 1985 Harley-Davidson XL/FX - Chrome Plated
1 review $32.60

Colony #7118-9 Acorn Head Cam Cover Screw Kit - 1957-1970 Harley-Davidson Sportster - Chrome Plated
$31.87

Colony #7802-1 Acorn Stem Nut 1936-1977 Harley-Davidson Springers - Chrome Plated
3 reviews $21.73

Colony #7620-1 Fork Tube Cap/Bolt/Breather 1947-1977 Harley-Davidson Glide Front Ends - Chrome Plated
$21.73

Colony #7613-2 Spring Retainer & Acorn Nut Set 1936-1948 Harley-Davidson Big Twin Springers 1936-1952 45's
$20.65

Colony #7207-8 Rear Fender Rail Screw 1954-1978 Harley-Davidson Sportster
$21.73

Colony #8149-12 Timing Cover Screw Kit 1936-1969 Harley-Davidson Big Twins - Chrome Plated
1 review $24.20

Colony #7349-3 Rocker Box Oil Line Fittings 1942-1947 Harley-Davidson Knucklehead - Chrome Plated
1 review $20.27

Colony #7018-16 High Crown Cylinder Base Nut Set - 1957-1985 Harley-Davidson Sportster - Chrome Plated
$21.60

Colony #8101-6 Swingarm End Cover Kit 1973-1984 Harley-Davidson FX/FL 1979-1992 XL 1981-1987 FXR - Chrome Plated
2 reviews $21.12

Colony #7408-10 Over Length Front Motor Mount Studs With Acorn Nuts 1957-1985 Sportster - Chrome Plated
3 reviews $21.12

Colony #8203-6 Front Fender Mounting Kit 1936-1948 Harley-Davidson Springers - CAD Plated
$20.85

Colony #8106-16 Cylinder Base Nuts & Lock Washers Harley-Davidson Sportster & 45's - Chrome Plated
2 reviews $20.11

Colony #7705-4 Knucklehead Rocker Box Drain Tube Fitting Kit
$20.31

Colony #8015-4 Rear Stand Mounting Kit 1938-1957 Harley-Davidson Big Twins & 1939-Up 45's - Parkerized
1 review $20.57

Colony #7818-5 Shifter Lever Stud & Bushing Kit 1936-1954 Harley-Davidson - CAD Plated
$19.51

Colony #8162-3 Front Axle Nut Kit 1946-1971 Harley-Davidson Big Twins - Chrome Plated
$18.72

Colony #7605-4 Rocker Arm Thrust And Packing Washer Kit 1936-1947 Harley-Davidson Knucklehead
$18.15

Colony #7820-4 Rear Brake Cross Shaft Nut & Lock Kit 1930-1957 Harley-Davidson Big Twins - CAD Plated
$17.92

Colony #7148-3 Oil Line/Vent Fitting - Pre-1965 Harley-Davidson Davidson Big Twin - Chrome Plated
1 review $17.22

Colony #7816-1 Acorn Motor Sprocket Nut 1955-1976 Harley-Davidson Big Twin - Chrome Plated
1 review $16.73

Colony #7351-2 Transmission Pug Standard Size 1940-1984 Harley-Davidson 74's
$15.94

Colony #7156-2 Self-Tapping Transmission Side Cover Oil Plug - 1936-1984 Harley-Davidson Big Twin - Chrome Plated
$15.94

Colony #7139-4 Lifter Base Bolt Kit - 1957-1985 Harley-Davidson Sportster - Chrome Plated
2 reviews $15.52

Colony #7821-6 Air Cleaner Mounting Screw & Lock Kit 1956-1965 Harley-Davidson Big Twins
$16.94

Colony #7609-6 Rocker Stud Lock Kit 1930-1948 Harley-Davidson Big Twin Springers
$15.14

Colony #8158-8 Linkert Carb Mounting Screws OEM #27422-39 - Chrome Plated
$14.74

Colony #8145-10 Circuit Breaker & Voltage Regulator Screws 1936-1964 Harley-Davidson OHV Twins - Chrome Plated
1 review $14.89

Colony #8118-1 Transmission Filler Plug 1936-Up Harley-Davidson Big Twins - Chrome Plated
1 review $16.50

Colony #8102-16 Lifter Base Screw Kit 1936-1953 Harley-Davidson Big Twin & 1937-1973 45's - Chrome Plated
$19.25

Colony #7612-3 Oil Line/Vent Line Fittings Pre-1965 Harley-Davidson Big Twins - CAD Plated
2 reviews $13.94

Colony #8107-16 Cylinder Base Nuts & Lock Washers Harley-Davidson Sportster & 45's - CAD Plated
$13.78

Colony #7155-4 Acorn Head Sprocket Cover Bolt Kit - 1971-1976 Harley-Davidson Sportster - Chrome Plated
$13.94

Colony #7154-2 Acorn Head Generator Screw Kit - 1971-1985 Harley-Davidson Sportster - Chrome Plated
$13.94

Colony #8009-2 Front Fender Brace Clip Lock Kit 1934-1948 Harley-Davidson Big Twins & 1940-1954 45's
$13.40

Colony #7801-2 Gas Tank Shut Off Operating Knob Extension 1940-65 Harley-Davidson
2 reviews $11.96

Colony #7107-1 Acorn Style Sprocket Nut - 1936-1954 Harley-Davidson Big Twins - Chrome Plated
2 reviews $11.56

Colony #8209-2 Generator Mounting Screws 1958-1973 Harley-Davidson 45's - Chrome Plated
$11.14

Colony #8146-10 Circuit Breaker & Voltage Regulator Screws 1936-1964 Harley-Davidson OHV Twins - CAD Plated
$10.04

Colony #7503-1 Oversized Drain Plug 1965-Up Harley-Davidson Big Twins 1967-Up Sportster - Chrome Plated
$10.04

Colony #7501-1 Oversize Timing Plug/Oil Tank Plug 11/16-16 Thread - Chrome Plated
$10.04

Colony #7106-1 Timing/Oil Plug - Harley-Davidson '74 Oil Tanks with 5/8-18 Thread - Chrome Plated
1 review $10.04

Colony #8207-2 Generator Screw Kit 1937-1957 Harley-Davidson 45's - Chrome Plated
$9.56

Colony #8200-10 Star Shaped Wheel Hub Outer Cover Screw Kit 1936-1966 Harley-Davidson - Chrome Plated
2 reviews $9.56

Colony #8159-8 Linkert Carb Mounting Screws OEM #27422-39 - CAD Plated
$9.56

Colony #8114-1 Timing Plug/Oil Tank Plug OEM #704 1952-1969 Harley-Davidson FL and XL -Chrome Plated
1 review $8.78

Colony #7815-4 Acorn Head License Plate Mounting Kit And Rubber Washers - Chrome Plated
1 review $8.93

Colony #8210-2 Generator Mounting Screws 1958-1973 Harley-Davidson 45's - CAD Plated
$8.78

Colony #8201-10 Star Shaped Wheel Hub Outer Cover Screw Kit Fits 1936-1966 Harley-Davidson - CAD Plated
$7.17

Colony #8152-2 Generator Screw Kit 1936-1957 Harley-Davidson Big Twin - CAD Plated
3 reviews $7.17

Colony #8119-1 Starter Crank Pin Stud 1936-Up Harley-Davidson Big Twins - Chrome Plated
2 reviews $7.17

Colony #8170-10 Cylinder Head Bolt Washers OEM #6469 All 1948-Up Harley-Davidsons - CAD Plated
$6.78

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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