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 #8442-19 Transmission Side Cover Clutch Arm Cap Nut Kit Harley-Davidson Big Twin 36-84 - Chrome Plated
$24.71

Colony #8438-16 Cylinder Base High Crown Cap Nut Set 1957-1985 Sportster 1969-Up Triumph - Chrome Plated
$21.60

Colony #8437-16 Cylinder Base High Crown Cap Nut Set 1930-1977 Harley-Davidson 74s - Chrome Plated
$21.66

Colony #8906-5-P Transmission Shifter Cover Smooth Allen Kit 1987 Harley-Davidson FX/FL - Chrome Plated
$11.90

Colony #2991-2 Generator Screw Kit Special 5/16 inch case holes Harley Big Twins 36-57 — Colony #2991-2 Special Generator Screw Kit 5/16 inch Case Holes 1936-1957 Harley-Davidson Big Twins - Parkerized
$12.10

Colony #2984-2 5 inch Heavy Duty Solo Seat Springs - Made in USA - Chrome Plated
16 reviews $18.14

Colony #2266-8-P Gas Tank Smooth Allen Mounting Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
1 review $11.90

Colony #2964-2 Generator Frame Screw Kit 1932-1957 Harley-Davidson Twins - Parkerized
$17.42

Colony #2962-6 Flat Top Brass Grease Fitting Alemite Pre-1938 Harley-Davidson - 3 Pack
$20.85

Colony #2957-2 Kick Starter Pedal Rubber Rod Kit 1917-Up Harley-Davidson - CAD Plated
$19.36

Colony #2956-2 Kick Starter Pedal Rubber Rod Kit 1917-Up Harley-Davidso - Parkerized
$19.36

Colony #2954-4 Throttle Cable Bracket 1948 Harley-Davidson OHV - Parkerized
$20.90

Colony #2854-6-P Upper Engine Mounting Kit 1984-1999 Harley-Davidson Softail - Chrome Plated
2 reviews $14.52

Colony #2226-4-P Sprocket Cover Smooth Allen Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$11.17

Colony #2530-6-P Fuel Tank Mounting Smooth Allen Kit 1985-1986 Harley-Davidson FXWG/FXST/FXSB/FXEF - Chrome Plated
$21.57

Colony #2529-6-P Rear Fender Rail Mounting Smooth Allen Kit 1957-1978 Harley-Davidson Sportster - Chrome Plated
$20.19

Colony #2523-5-P Fuel Tank Smooth Button Head Mounting Kit 1988-1994 Harley-Davidson FXR - Chrome Plated
1 review $13.92

Colony #2522-6-P Rear Fender Rail Mounting Smooth Allen Screw Kit 1973-1984 Harley-Davidson FX - Chrome Plated
$19.48

Colony #2404-6-P Transmission Shifter Cover Smooth Allen Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$13.22

Colony #2524-2-P Fuel Tank Smooth Mounting Kit Pre-1984 Harley-Davidson Big Twins - Chrome Plated
1 review $10.44

Colony #8795-4-P Handlebar Clamp Smooth Allen Screw Kit 1974-1971 Harley-Davidson FX/XL L1977-1984 FL - Chrome Plated
$10.04

Colony #2222-11-P Cam Cover Smooth Allen Screw Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$23.01

Colony #2177-8-P Footrest Gear Shifter Smooth Allen Mounting Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$14.89

Colony #2176-8-P Frame Assembly Smooth Allen Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$19.36

Colony #8784-4-P Sprocket Cover Smooth Allen Screw Kit 1971-1976 Harley-Davidson Sportster - Chrome Plated
$7.82

Colony #8475-4 Anti-Vibration License Plate Mounting Cap Nut Kit - Chrome Plated
1 review $7.96

Colony #8470-8 Lifter Base Cap Screw Kit 1976-Up Harley-Davidson 74s - Chrome Plated
$27.89

Colony #9959-38-P Primary Cover Mounting Kit Smooth Allen Kit 1999-Up Harley-Davidson FLT - Chrome Plated
1 review $33.84

Colony #2273-7-P Upper Triple Clamp Covers Fork Slider Bottom Smooth Allen Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$9.31

Colony #9797-20-P Front Motor Mount Smooth Allen Kit 1957-1985 Harley-Davidson Ironhead Sportster - Chrome Plated
2 reviews $60.83

Colony #2978-4 Chain Guard Stud 1930-1936 Harley-Davidson VL - CAD Plated
$9.68

Colony #9767-15-P Primary Cover Smooth Allen Screw Kit 1991-1993 Harley-Davidson XL - Chrome Plated
1 review $27.07

Colony #8790-28-P Rocker Box Smooth Allen Bolt Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
2 reviews $38.59

Colony #8441-1 Timing/Oil Plug All Harley-Davidson Timing Plug and 74s Oil Tanks - Chrome Plated
$8.78

Colony #8789-28-P Rocker Box Smooth Allen Bolt Kit 1957-1976 Harley-Davidson Sportster - Chrome Plated
$33.50

Colony #8763-20-P Primary Cover Smooth Allen Screw Kit 1980-1984 Shovelhead & Evo 5 speed - Chrome Plated
$37.22

Colony #9932-8-P Intake Manifold to Cylinder Smooth Allen Kit 1995-Up Harley-Davidson Big Twin/XL - Chrome Plated
1 review $9.35

Colony #8737-24-P Valve Cover Smooth Allen Screw Kit Harley-Davidson Panhead With Steel D Rings - Chrome Plated
$33.84

Colony #8782-4-P Lifter Base Smooth Allen Screw Kit 1957-1990 Harley-Davidson Sportster - Chrome Plated
1 review $9.56

Colony #8457-20 Heat Treated Cap Style Head Bolt Kit 1948-1983 Harley-Davidson Panhead/ Shovelhead - Chrome Plated
$66.63

Colony #8440-12 Rocker Box Cap Bolt Set 1936-1947 Harley-Davidson Knucklehead - Chrome Plated
$27.51

Colony #2988-3 Crankcase Breather Stud and Pipe 1939-1947 Harley-Davidson Knuckleheads - Parkerized
$36.00

Colony #2979-28 Stock Fastener Motor Case Kit 1930-1936 Harley-Davidson VL - CAD Plated
1 review $51.70

Colony #2967-10 Grade 8 Head Bolt Kit 1977-1984 Harley-Davidson Shovelhead - Chrome Plated
1 review $65.99

Colony #2966-10 Grade 8 Head Bolt Kit 1977-1984 Harley-Davidson Shovelhead - CAD Plated
3 reviews $44.00

Colony #8797-4-P Handlebar Lever Mount Smooth Allen Screw Kit Pre-1972 Harley-Davidson FX/FL/XL - Chrome Plated
$6.38

Colony #2470-20-P Primary Cover Smooth Allen Screw Kit 2007-Up Harley-Davidson Softail - Chrome Plated
$41.75

Colony #9783-4-P Headlight Visor Mounting Bolt Kit Smooth Chrome Allen Harley XL FX FXR 1959-up — Colony #9783-4-P Headlight Visor Smooth Allen Mounting Kit 1959-Up Harley-Davidson XL/FX/FXR - Chrome Plated
$5.58

Colony #2401-15-P Transmission Side Cover Smooth Allen Screw Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$29.43

Colony #2172-16-P Alternator and Derby Cover Smooth Allen Mounting Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$28.77

British Standard Main Roller Bearing for 1966 - 1972 Triumph 650 Unit Twin Motorcycles OEM #70-2879
13 reviews $204.42

British Standard JRC 30mm Carburetor Set for 1979 - 1982 Triumph T140 750 Motorcycles
3 reviews $268.39

Wassell Stator 12 volt 10 amp 120 watt for Triumph BSA Norton
16 reviews $127.89

British Standard 1/4 inch BSP Petcock Fuel Valve - Reserve - UK Made For Triumph BSA Norton
14 reviews $53.20

Kustom Tech Deluxe 7/8 inch Clutch Lever - Polished Aluminum & Brass
$243.43

Kustom Tech Deluxe 7/8 inch Brake Lever - Polished Aluminum & Brass
$242.19

Kustom Tech Classic 1 inch Brake Lever - Black
$259.35

Kustom Tech Deluxe 7/8 inch Master Cylinder - Polished Aluminum & Brass
3 reviews $461.22

Kustom Tech Classic 7/8 inch Master Cylinder - Black
$517.14

Kustom Tech Classic 1 inch Master Cylinder - Black
1 review $500.62

EMGO Pistons for Triumph 650 c.c. Motorcycles - +0.060
4 reviews $124.01

EMGO Pistons for Triumph 650 c.c. Motorcycles - Standard
2 reviews $124.01

Amal Carburetor Amal Carburetor Main Jets - 250
2 reviews $10.68

EMGO Pistons for Triumph 650 c.c. Motorcycles - +0.040
2 reviews $124.01

EMGO Pistons for Triumph 650 c.c. Motorcycles - +0.020
4 reviews $124.01

Amal Carburetor Amal Carburetor Main Jets - 160
3 reviews $13.26

Amal Carburetor 930 MK1 Premier Concentric Aluminum 30mm Carburetor for Triumph TR6 & TR7 Tiger
22 reviews $432.04

British Standard JRC / PWK / Keihin Carburetor - P26-140 Main Jet (Amal 230)
1 review $8.78

British Standard JRC / PWK / Keihin Carburetor - P26-138 Main Jet (Amal 220)
$8.78

British Standard JRC / PWK / Keihin Carburetor - P26-142 Main Jet (Amal 240)
$8.78

British Standard JRC / PWK / Keihin Carburetor - P26-135 Main Jet (Amal 210)
1 review $8.78

British Standard JRC / PWK / Keihin Carburetor - P26-132 Main Jet (Amal 200)
1 review $8.78

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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Custom Motorcycle Parts FAQ

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