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

British Standard JRC / PWK / Keihin Carburetor - P26-130 Main Jet (Amal 190)
5 reviews $8.78

British Standard JRC / PWK / Keihin Carburetor - P26-128 Main Jet (Amal 180)
$8.79

British Standard JRC / PWK / Keihin Carburetor - P26-112 Main Jet (Amal 150)
3 reviews $8.78

British Standard JRC / PWK / Keihin Carburetor - P26-110 Main Jet (Amal 140)
1 review $8.78

Lowbrow Customs Competition Screw-In Gas Cap for Harley-Davidson 1996 & later - Black
32 reviews $42.17 $51.50

Morris Magneto M-5 Magneto for Alternator Big Twin Harley Davidsons 1970 - 1973 - Brushed Finish
$2,395.00

Colony #2934-2 Clutch Adjusting Hole Allen Style Filler Cap 1977-1985 Harley-Davidson Sportster - Chrome Plated
$36.20

Colony #2932-2 Clutch Adjusting Hole Allen Style Cap 1971-1976 Harley-Davidson Sportster - Chrome Plated
$36.20

Colony #2930-4 Primary Cover Cap Allen Style 1954-1976 Harley-Davidson Sportster - Chrome Plated
1 review $36.94

Colony #2846-3 Wheel Bearing Locknut/Seal Kit Harley-Davidson XL/FL/FLH/FX/Sidecar/Servi-car - Chrome Plated
$36.30

Colony #2778-4 Tail Light Bracket Mounting Kit 1947-1948 Harley-Davidson Tombstone
2 reviews $4.54

Colony #2614-7 Axle Mounting Kit 1933-1965 Harley-Davidson Sidecars - Parkerized
3 reviews $36.85

Colony #2812-4 Front Axle Nut and Smooth Spacer Kit 2004-2007 Harley-Davidson VRSC - Chrome Plated
$40.70

Colony #2579-18 Footboard Mounting Kit 1935-1973 Harley-Davidson 45s/Servi-car - Parkerized
3 reviews $49.75

Colony #2933-1 Clutch Side Nut 1936-1940 Harley-Davidson Big Twin Knuckelhead
$41.80

Colony #2822-1 Oversized Linkert Carburetor Venturi 1-1/16 inch OEM #27362-30 Harley-Davidson
$41.97

Colony #2818-1 Oversized Linkert Carburetor Venturi 1-5/16 inch OEM #27363-41 Harley-Davidson
$43.32

Colony #2787-5 Front Axle Smooth Spacer Kit 2009-Up Harley-Davidson Trike - Chrome Plated
2 reviews $43.45

Colony #2714-36 Instrument Panel Base Restoration Kit 1939-1946 Harley-Davidson Big Twins
1 review $49.50

Colony #2574-3 Footpegs And Shifter Pike Nuts Harley-Davidson Chopper - Chrome Plated
1 review $49.50

Colony #2781-6 Springer Spring Rod Kit 1931-1937 Harley-Davidson 45s
$57.94

Colony #2584-7 Steering Damper Upper Kit 1936-1948 Harley-Davidson Big Twin - Chrome Plated
$58.30

Colony #2908-2 Oil Tank Filler Cap and Gauge 1941-1964 Harley-Davidson Big Twins - Parkerized
$71.50

Colony #2904-2 Oil Tank Filler Cap and Gauge 1941-1964 Harley-Davidson Big Twins - CAD Plated
1 review $71.50

Colony #2903-2 Oil Tank Filler Cap and Gauge 1936-1940 Harley-Davidson Big Twins - CAD Plated
1 review $71.50

Colony #2677-10 Extra Long Seat Post Rod Nuts Spacers Kit 1936-1980 Harley-Davidson Big Twins
$82.50

Colony #2659-10 Seat Post Rod Nuts and Spacers Kit 1929-1973 Harley-Davidson 45s/Servicar
2 reviews $82.50

Colony #2612-10 Seat Post Rod Nuts Spacer Kit 1936-1980 Harley-Davidson Big Twins
$82.50

Colony #2583-10 Seat Post Rod/Nuts/Spacers Kit Harley-Davidson WLA/WLC
$82.50

Colony #2747-8 Rear Axle Adjusters Swingarm End Cover Kit 1997-2001 Harley-Davidson FLT - Zinc Plated
3 reviews $35.20

Colony #2642-20 Valve Spring Cover Kit 1931-1941 Harley-Davidson Davidson 45's - CAD Plated
$105.60

Colony #2609-4 Instrument Panel Dash Base Contact Spring Kit 1936-1946 Harley-Davidson Big Twins
$35.75

Colony #2902-2 Pike Spike Rear Axle Covers 2008-Up Harley-Davidson Dyna 2013-Up XL - Chrome Plated
3 reviews $54.14

Colony #2577-1 Boot Guard 1936-Up Harley-Davidson Knucklehead/Flathead - Chrome Plated
$99.00

Colony #2941-22 Complete Springer Rocker Rebuild Kit 1930-1952 Harley-Davidson 45 Solo - Parkerized
2 reviews $191.54

Colony #2943-1 Boot Guard 1936-Up Harley-Davidson Knucklehead/Flathead - Black Powder Coated
$95.70

Colony #2716-8 Spring to Frame Mounting Kit 1925-1984 Harley-Davidson Sidecars - Parkerized
3 reviews $64.90

Colony #2615-7 Fender Inner Brace Clip Bracket Mounting Kit 1936-1965 Harley-Davidson Sidecars - Parkerized
$62.06

Colony #2613-4 Custom Smooth Rear Axle Nut Lock Spacers 2002-2007 Harley-Davidson Touring - Chrome Plated
2 reviews $46.81

Colony #2692-5 Lower Front Mount Tie Bar Assembly 1924-1984 Harley-Davidson Sidecars - Parkerized
$37.40

Colony #2945-1 Cylinder Bracket for Aluminum Heads 1936-1952 Harley-Davidson WL 45 1936-1973 Servi-car - Parkerized
1 review $37.00

Colony #2826-3 Rear Wheel Bearing Locknut and Seal 1955-1978 Harley-Davidson Sportster - CAD Plated
$33.00

Colony #2656-8 Spark Coil and Cover Mounting Kit 1955-1966 Harley-Davidson KH/Sportster - CAD Plated
1 review $33.00

Colony #2690-1 Lower Front Mount Tie Rod Ball Joint 1924-1984 Harley-Davidson Sidecars
$31.90

Colony #2720-6 Rear Brake Shoe Pivot Stud and Cup Assembly 1938-1957 Harley-Davidson Big Twin - Parkerized
2 reviews $31.90

Colony #2766-4 Sidecar Spring Bushing Kit 1937-1984 Harley-Davidson Sidecars
1 review $30.80

Colony #2761-5 Kick Starter Pedal Axle Kit 1916-1962 Harley-Davidson - CAD Plated
2 reviews $30.25

Colony #2817-18 Oversized Top of Tank Screw and Washer Repair Kit 1918-1952 Harley-Davidson - Parkerized
$30.04

Colony #2668-21 Lower Motor Mount Acorn Kit 1993-2003 Harley Sportster - Chrome Plated
1 review $33.67

Colony #2937-5 Stem Nut Kit with Washer/Cover Harley-Davidson Wideglide Without Steering Damper - Chrome Plated
1 review $25.29

Colony #2813-8 Clutch Arm Rebuilding Kit 1944-1952 Harley-Davidson 45 Solo - Parkerized
$24.98

Colony #2708-5 Linkert Low Speed Needle Valve 3-1/16 inch Needle 1933-1947 Harley-Davidson
$25.30

Colony #2703-7 Gas Tank Shut Off Rod Upper Kit 1940-1965 Harley-Davidson Big Twin/45s - Parkerized
$25.85

Colony #2873-1 Rear Axle Spacer 1958-1966 Harley-Davidson FL/FLH - Chrome Plated
$23.65

Colony #2821-3 Gas Tank Fitting Kit 1940-1949 Harley-Davidson Big Twin - Chrome Plated
1 review $28.00

Colony #2737-1 Fork Tube Cap/Plug 1984-2001 Harley-Davidson FLT - Chrome Plated
1 review $24.26

Colony #2593-5 Front Brake Control Wire Lower Connection Kit 1928-1948 Harley-Davidson Big Twins 1928-1950 45s - Parkerized
4 reviews $24.20

Colony #2938-4 Primary Cover Allen Style Filler Cap & Breather 1954-1976 Harley-Davidson Sportster
$23.10

Colony #2775-12 Undersize Clutch Backing Plate Stud Spacer Kit 1979-1984 Harley-Davidson Sportster
$23.10

Colony #2756-12 Clutch Backing Plate Stud Spacer Kit 1979-1984 Harley-Davidson Sportster
1 review $23.10

Colony #2719-22 Exhaust System Mounting Bolt Kit 1941-1957 Harley-Davidson Knucklehead/Panhead - Chrome Plated
$27.72

Colony #2940-2 Clutch Adjusting Hole Allen Style Cap 1971-1976 Harley-Davidson Sportster
$20.90

Colony #2890-1 Front Axle Spacer 1936-1948 Harley-Davidson Big Twin Springers 1942-1943 WLC 1941-1957 Servi-car - Chrome Plated
1 review $20.90

Colony #2855-7 Rear Caliper Stabilizer Bracket Bolt Kit 1980-1985 Harley-Davidson FLT - Zinc Plated
2 reviews $22.00

Colony #2772-22 Exhaust System Mounting Bolt Kit 1941-1957 Harley-Davidson Knucklehead/Panhead - Parkerized
$25.08

Colony #2738-4 Clutch Hub Nut Lock Gear Oil Seal Kit 1956-1966 Harley-Davidson KH/XL/XLH/XLCH 1967-1969 XLCH
1 review $22.00

Colony #2654-6 Clutch Foot Lever Mounting Kit 1947-1973 Harley-Davidson Servi-car and WR Racing Models
$20.35

Colony #2800-16 Brake Rear Drum Bolt Kit 1952-1965 Harley-Davidson K/KH/XL - Chrome Plated
$24.00

Colony #2910-6 Rear Stand Mounting Kit 1936 Harley-Davidson OHV 1937 Side Valve Big Twins - Parkerized
$17.52

Colony #2898-1 Motor Sprocket Nut 1970-1990 Harley-Davidson Big Twins
$19.36

Colony #2889-1 Front Axle Spacer 1936-1948 Harley-Davidson Big Twin Springers 1942-1943 WLC 1941-1957 Servi-car - Parkerized
$16.94

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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