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 #9102-8 Cylinder Base Nut Set 1978-1984 Harley-Davidson Shovelhead OEM #16838-78 - Black Oxide
2 reviews $20.35

Colony #9101-8 Cylinder Base Nut Set Zinc 1978-1984 Harley-Davidson Shovelhead OEM #16838-78 - Zinc Plated
1 review $20.35

Colony #9817-15 Electrical Terminal Plate 1970-1974 Harley-Davidson FX/XL - Parkerized
2 reviews $25.00

Colony #9773-8 Center Motor Mount Kit Acorn Nut 1986-2003 Harley-Davidson Sportster - Chrome Plated
$16.73

Colony #9762-16 Oil Pump Mounting Kit Allen 1992-Up Harley-Davidson Big Twin - Chrome Plated
1 review $16.38

Colony #9636-8 Handlebar Clamp & Gauge Mount Kit 1983-1994 Harley-Davidson FX/XL - Chrome Plated
$15.94

Colony #9623-16 Cylinder Base Nuts 1936-1978 Harley-Davidson Big Twins - Parkerized
3 reviews $15.64

Colony #9737-1 Gear Box Adjusting Screw 1936-1964 Harley-Davidson Big Twin - Parkerized
1 review $15.52

Colony #9693-1 Gear Box Adjusting Screw 1929-Up Harley-Davidson 45's - Parkerized
$15.52

Colony #9622-16 Lifter Base Screw Kit 1936-1953 Harley-Davidson Big Twin 1937-1973 45's - Parkerized
2 reviews $16.35

Colony #9515-2 Rear Axle Adjusting Screw 1993-1999 Harley-Davidson FXST OEM #47579-93 - Chrome Plated
1 review $18.16

Colony #9401-1 Aluminum Transmission Filler Plug 1958-1980 Harley-Davidson Big Twin
2 reviews $15.52

Colony #9834-8 Chrome Countersink Washer Set for 1/4" Flat Head Socket Harley-Davidson - Chrome Plated
$15.14

Colony #9607-2 Oil Pump Relief Valve Plug 1968-1980 Harley-Davidson Big Twin - Chrome Plated
$15.14

Colony #9605-2 Oil Pump Relief Valve Plug 1954-1967 Harley-Davidson Big Twin - Chrome Plated
3 reviews $15.14

Colony #9107-8 Rear Brake Caliper Anchor Arm Bolt Kit 1973-1983 Harley-Davidson FL/FX - CAD Plated
1 review $15.13

Colony #9017-5 Air Cleaner Mounting Screw & Lock Kit 1936-1955 Harley-Davidson Twins - CAD Plated
$16.94

Colony #9214-2 Handlebar End Nuts 1954-1972 Harley-Davidson K/XL 1954-1974 FL OEM #56288-53 - Black
$14.89

Colony #9814-16 Lifter Base Screw Kit 1/4-20 Harley-Davidson Aftermarket Case - Chrome Plated
1 review $17.69

Colony #9682-5 Air Cleaner Mounting Screw & Lock Kit 1936-1955 Harley-Davidson Twins - Parkerized
1 review $16.94

Colony #9721-2 Cylinder Head Bolt Spacers 1937-1973 Harley-Davidson 45's - Parkerized
$13.94

Colony #9713-1 Stem Nut for Harley-Davidson 45 Springers - Parkerized
1 review $13.94

Colony #9603-2 Oil Screen Plug 1952-1965 Harley-Davidson Big Twin - Chrome Plated
$14.34

Colony #9863-5 Transmission Case Bottom Stud Kit 1984-Up Harley-Davidson Softail
1 review $13.55

Colony #9779-5 Top Motor Mount Hardware Kit 1932-Up Harley-Davidson 45's - Chrome Plated
$13.55

Colony #9624-16 Cylinder Base Nuts Harley-Davidson Sportster & 45's - Parkerized
$13.78

Colony #9633-50 Flatwashers Harley-Davidson FL/FX/XL OEM #6099 - Chrome Plated
7 reviews $14.52

Colony #9644-2 Oil Screen Plug 1981-Up Harley-Davidson FL/FX - Chrome Plated
$11.96

Colony #9526-1 Oil Pump Bypass Valve Plug 1936-1952 Harley-Davidson Big Twin 1937-Up UL/45s - Chrome Plated
$11.96

Colony #9819-12 Timing Cover Allen Screw Kit 1993-Up Harley-Davidson Big Twin - Chrome Plated
2 reviews $11.90

Colony #9771-8 Center Motor Mount Allen Screw Kit 1986-2003 Harley-Davidson Sportster - Chrome Plated
1 review $11.90

Colony #9604-2 Oil Screen Plug 1952-1965 Harley-Davidson Big Twin - CAD Plated
$11.14

Colony #9753-9 Primary Cover Allen Screw Kit 1957-1969 Harley-Davidson XLCH - Chrome Plated
1 review $10.76

Colony #9600-5 Disc Brake Rotor to Hub Allen Screw Kit 1974-1980 Harley-Davidson FX 1974-1977 XL - Chrome Plated
$10.76

Colony #9204-3 Clutch Lever Rod Bolt 1952-1964 Harley-Davidson Big Twin OEM #36921-52 - CAD Plated
$10.37

Colony #9706-4 Shifter Rod End Bolt Kit 1936-1954 Harley-Davidson Handshift 1951-1964 Footshift - Parkerized
$9.96

Colony #9671-20 Transmission Side Cover & Clutch Arm Nut Kit Pre-1984 Harley-Davidson 4 Speed - Parkerized
4 reviews $9.96

Colony #9109-2 Generator Screws 1930-1948 Harley-Davidson Big Twin Sidevalves OEM #1523-30 - CAD Plated
2 reviews $10.37

Colony #9672-8 Linkert Carb Mounting Screws Harley-Davidson OEM #27422-39 - Parkerized
2 reviews $9.56

Colony #9527-1 Oil Pump Bypass Valve Plug 1936-1952 Harley-Davidson Big Twin 1937-Up UL/45s - CAD Plated
$9.56

Colony #9787-12 Oil Pump Mounting Kit Stock 1978-1991 Harley-Davidson Big Twins - Zinc Plated
$8.78

Colony #9502-1 Timing & Oil Tank Plug 1938-1951 Harley-Davidson All Models OEM #2326-38 - Chrome Plated
$9.56

Colony #9304-1 Oversize Harley-Davidson Timing & Oil Tank Plug - Chrome Plated
1 review $8.78

Colony #9840-8 Chrome OEM Style Rocker Shaft End Nut 1936-1947 Harley-Davidson Knucklehead - Chrome Plated
$9.16

Colony #9744-7 Rear Chain Guard Mounting Kit 1936-1952 Harley-Davidson 45 Solo Pre-1973 Servicar - Chrome Plated
1 review $7.96

Colony #9649-5 Speedometer Cable Clamp 1939-1948 Harley-Davidson 74/80 Sidevalve - Parkerized
$13.20

Colony #9645-2 Oil Screen Plug 1981-Up Harley-Davidson FL/FX - CAD Plated
$7.96

Colony #9687-5 Transmission Screw Kit 1929-1973 Harley-Davidson 45's - Parkerized
$9.10

Colony #9651-1 Speedometer Cable Clamp 1957-1961 Harley-Davidson OHV Big Twins - Parkerized
$7.58

Colony #9650-1 Speedometer Cable Clamp 1952-1956 Harley-Davidson OHV Big Twins - Parkerized
$7.58

Colony #9646-1 Speedometer Cable Clamp 1936-1938 Harley-Davidson 74/80 Sidevalve 1936-1951 61/74 OHV - Parkerized
2 reviews $7.58

Colony #9414-8 Circuit Breaker & Relay Screw Kit 1937-1973 Harley-Davidson 45's - Chrome Plated
$7.58

Colony #9403-1 Timing Plug 1970-Up Harley-Davidson OEM #720 - CAD Plated
3 reviews $9.35

Colony #9301-5 Transmission Screw Kit 1929-1973 Harley-Davidson 45's - CAD Plated
$9.10

Colony #9652-1 Speedometer Cable Clamp 1961-1980 Harley-Davidson OHV Big Twins - Zinc Plated
$7.17

Colony #9615-10 Oil Pump Mounting Kit Late 1971-1976 Harley-Davidson Sportster - CAD Plated
$7.17

Colony #9712-2 Generator Screw Kit 1937-1957 Harley-Davidson 45's - Parkerized
1 review $6.78

Colony #9704-10 Cylinder Head Bolt Washers 1936-Up Harley-Davidson - Parkerized
$6.78

Colony #9520-4 Generator Pole Screw Kit 1918-1957 Harley-Davidson Twins OEM #30280-18 - Parkerized
$6.78

Colony #9508-4 Handlebar Bolt Kit 1936-1948 Harley-Davidson Big Twin Springers 1940-Up 45 Springers - Parkerized
$9.68

Colony #9504-1 Timing & Oil Tank Plug 1938-1951 Harley-Davidson All Models OEM #2326-38 - Parkerized
1 review $8.80

Colony #9218-4 Handlebar Bolt Kit Harley-Davidson 1936-1948 Big Twin Springers 1940-Up 45 Springers - CAD Plated
$9.68

Colony #9841-8 Rocker Shaft End Nut Kit 1936-1947 Harley-Davidson Knucklehead - CAD Plated
$6.38

Colony #9734-7 Foot Brake Lever & Bracket Mounting Kit 1936-1971 Harley-Davidson Big Twin - Parkerized
2 reviews $6.38

Colony #9733-7 Foot Brake Lever & Bracket Mounting Kit CAD Harley-Davidson 1936-71 - CAD Plated
2 reviews $6.38

Colony #9665-8 Circuit Breaker & Relay Screw Kit 1937-1973 Harley-Davidson 45's - Parkerized
$5.96

Colony #9415-8 Circuit Breaker & Relay Screw Kit 1937-1973 Harley-Davidson 45's - CAD Plated
$5.96

Colony #9784-4 Headlight Visor Mounting Hex Bolt Kit 1959-Up Harley-Davidson XL/FX/FXR - Chrome Plated
$5.58

Colony #9717-1 Starter Crank Pin Stud 1936-Up Harley-Davidson Big Twin - Parkerized
$5.18

Colony #9674-1 Long Oil Pump Nut Pre-1967 Harley-Davidson All Models - Parkerized
$5.18

Colony #9821-4 Oil Filter Adaptor Mounting Allen Kit 1992-Up Harley-Davidson Big Twin - Chrome Plated
1 review $4.76

Colony #9731-3 Gas Strainer Rebuild Kit 1939-1941 Harley-Davidson Twins
$4.76

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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