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

Colony #2589-1 Oversized Timing Oil Tank Plug Harley-Davidson - Parkerized
2 reviews $8.80

Colony #2588-1 Oversized Timing Oil Tank Plug Harley-Davidson - CAD Plated
$8.80

Colony #2878-3 Starter Crank Pin Stud Kit 1936-Up Harley-Davidson Big Twins - CAD Plated
2 reviews $6.05

Colony #2773-1 Grease Nipple Front Wheel Brake 1936-1936 Harley-Davidson 45s - Parkerized
$6.05

Colony #2631-8 Front Crash Bar Mounting Kit 1951-1954 Harley-Davidson Big Twin - CAD Plated
$6.36

Colony #2586-1 Timer Cable Clamp 1949-1964 Harley-Davidson Big Twin - CAD Plated
1 review $7.26

Colony #2733-2 Fork Slider Drain Screws 1949-1977 Harley-Davidson FL - CAD Plated
$3.99

Colony #2647-3 Shifter Rod Clevis Pin Kit 1941-1952 Harley-Davidson 45's - Parkerized
$4.24

Colony #2760-3 Front Brake Cable to Fork Clip 1936-1948 Harley-Davidson Big Twin 1941-1957 45s 1941-Up Servi-car - Parkerized
2 reviews $7.15

Colony #2620-7 Frame Brace Upper Connection Kit 1937-1979 Harley-Davidson Sidecars - Parkerized
1 review $49.50

Cycle Standard Gloss Black Kickstand - 1 inch Under - 2004 - 2019 XL Sportster Models
5 reviews $78.59

Cycle Standard Chrome Kickstand - 1 inch Under - 2004-2022 Harley-Davidson XL Models - OEM #50185-04C
11 reviews $60.81

Colony #2442-8 High Performance Cylinder Studs 1983-1999 Harley-Davidson Big Twin Evo
$120.18

Colony #2212-1 Harley-Davidson Gas Strainer Assembly - 1/4 inch Barbed Fitting - CAD Plated
2 reviews $76.76

Colony #2497-38 Rear Fender Strut Low Profile Mounting Kit 2003-Up Harley-Davidson FX 2004-Up FL/Softail - Chrome Plated

1 $67.05

#2510-5 Chrome Rear Axle Nut Washer Spacers Kit Harley Sportster 08-up — Colony #2510-5 Rear Axle Nut Washer Spacers Kit 2008-Up Harley-Davidson Sportster - Chrome Plated
$54.14

Colony #2447-2 Rear Axle Pike Nut Covers 2005-2007 Harley-Davidson Sportster - Chrome Plated
1 review $54.14

Colony #2393-2 Pike Nut Front Axle Cover 2004-2007 Harley-Davidson Dyna 2000-2007 Touring Models - Chrome Plated
$54.14

Colony #2262-4 Pike Nut Headbolt Covers 1985-Up Harley-Davidson FL/FX/XL - Chrome Plated
$54.14

Colony #2183-16 Cylinder Head Studs 1929-1950 Harley-Davidson 45s Cast Iron Head - Parkerized
$60.91

Colony #2389-7 Front Axle Nut Spacer Washer Kit 2007-Up Harley-Davidson FXSTD - Chrome Plated
$53.13

Colony #2232-4 Headbolt Smooth Covers 1985-Up Harley-Davidson FL/FX/XL - Chrome Plated
1 review $52.14

Colony #2299-10 Front Brake Shackle Rebuilding Kit 1936-1938 Harley-Davidson Big Twin/45's
$81.21

Colony #2298-10 Front Brake Shackle Rebuilding Kit 1930-1936 Harley-Davidson VL
1 review $81.21

#2515-5 Chrome Front Axle Nut Washer Spacers Harley Dyna 08-up FXDWG FXDF — Colony #2515-5 Front Axle Nut Washer Spacers 2008-Up Harley-Davidson FXDWG/FXDF - Chrome Plated
$43.45

Colony #2432-18 Head Bolt Tapered Washer Kit Harley-Davidson Flatheads With Aluminum Heads
$44.00

Colony #2507-5 Front Axle Nut Spacers Washer Kit 2008-Up Harley-Davidson FLH/FLT - Chrome Plated
$43.45

Colony #2339-5 Front Axle Nut Spacer Washer Kit 2006-2007 Harley-Davidson Dyna FXD/FXDLI/FXDI/FXDCI/FXDBI - Chrome Plated
$43.45

Colony #2338-1 Linkert Carburetor Venturi 1-15/16 inch OEM #27363-41
$43.32

#2256-5 Chrome Front Axle Nut Spacers Washer Kit Harley Dyna 04-05 — Colony #2256-5 Front Axle Nut Washer Spacers Kit 2004-2005 Harley-Davidson Dyna - Chrome Plated
$43.45

Colony #2281-18 Spark Coil Mounting Kit 1937-1947 Harley-Davidson Big Twins - Parkerized
$47.38

Colony #2205-4 Swing Arm Pivot Hex Bolts 1984-1999 Harley-Davidson Softail - Chrome Plated
$47.38

Colony #2508-4 Rear Axle Nut Spacers Kit 2008-Up Harley-Davidson Touring Models - Chrome Plated
$46.81

#2390-5 Chrome Front Axle Nut Spacer Washer Kit Harley FLSTC FLSTN 07-up — Colony #2390-5 Front Axle Nut Spacer Washer Kit 2007-Up Harley-Davidson FLSTC/FLSTN - Chrome Plated
6 reviews $45.54

Colony #2493-6 Rear Fender Frame Clamp Bolt Kit 1936-1957 Harley-Davidson Big Twin - Parkerized
1 review $42.38

Colony #2380-36 Transmission Top Cover Mounting Kit 1931-1936 Harley-Davidson VL - Parkerized
$42.38

Colony #2379-36 Transmission Top Cover Mounting Kit 1915-1930 Harley-Davidson Twins - Parkerized
$42.38

Colony #2407-8 Chain Adjuster Swingarm End Cover Kit 1985-1996 Harley-Davidson FLT - Chrome Plated
$41.29

Colony #2456-10 Tool Box Mounting Kit 1931-1934 Harley-Davidson Twins - Parkerized
$39.22

Colony #2446-2 Axle Adjuster Smooth Covers 1993-2004 Harley-Davidson Sportster - Chrome Plated
$37.95

Colony #2220-24 Primary Cover Allen Screw Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
2 reviews $36.54

Colony #2211-5 Front Axle Nut Spacers/Washer Kit 2001-2006 Harley-Davidson FXSTD/FXSTDI - Chrome Plated
$35.74

Colony #2498-1 Pike Nut Fork Tube Cap/Plug 1973-1985 Harley-Davidson Sportster - Chrome Plated
$35.42

Colony #2444-2 Axle Adjuster Pike Nut Covers 2005-Up Harley-Davidson Sportster - Chrome Plated
$35.42

Colony #2470-20 Primary Cover Allen Screw Kit 2007-Up Harley-Davidson Softail - Chrome Plated
2 reviews $34.16

Colony #2340-10 Sprocket Bolt and Washer Polished Allen Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
$33.84

Colony #2306-16 Electrical Terminal Plate 1959-1969 Harley-Davidson Big Twin
$33.84

Colony #2305-12 Electrical Terminal Plate 1949-1957 Harley-Davidson Big Twin
3 reviews $33.84

Colony #2228-16 Motor Mount Button Allen Kit 2000-Up Harley-Davidson Sportster - Chrome Plated
$33.84

Colony #2452-2 Clutch Tension Adjusting Nut and Lock Washer 1936-1940 Harley-Davidson Big Twin - Parkerized
$31.63

Colony #2443-2 Rear Axle Covers Smooth 1989-2004 Harley-Davidson Sportster - Chrome Plated
1 review $31.63

#2371-1 Fork Tube Bolt OEM 45993-86 Harley XL FX 85-87 — Colony #2371-1 Fork Tube Bolt 1985-1987 Harley-Davidson XL/FX - Chrome Plated
$31.50

Colony #2445-2 Rear Axle Covers Smooth 2005-2007 Harley-Davidson Sportster - Chrome Plated
1 review $31.13

Colony #2276-10 Sprocket 12 Point Bolt and Nut Kit 1973-Up Harley-Davidson Big Twin and XL - Chrome Plated
4 reviews $30.79

Colony #2275-10 Sprocket 12 Point Bolt and Nut 1985-1992 Kit Harley-Davidson Big Twin - Chrome Plated
1 review $30.79

Colony #2367-8 Cylinder Base Stud Set 1929-1957 Harley-Davidson 45s
1 review $35.00

Colony #2531-12 Fender Brace And Fork Mounting Kit 1974-1984 Harley-Davidson XL/FX - Chrome Plated
$30.36

#2372-1 Fork Tube Bolt OEM 45993-73 Harley XL FX 73-85 — Colony #2372-1 Fork Tube Cap/Bolt 1973-1985 Harley-Davidson XL/FX - Chrome Plated
1 review $32.60

Colony #2474-19 Transmission Side Cover Allen Screw Kit 2007-Up Harley-Davidson Softail - Chrome Plated
$29.10

Colony #2419-8 Cylinder Base Pike Nut Set 1978-1984 Harley-Davidson Shovelhead - Chrome Plated
$29.73

Colony #2383-24 Transmission Side Cover Mounting Kit 1931-1936 Harley-Davidson VL - Parkerized
$28.47

Colony #2316-5 Foot Brake Lever Stud 1939-1957 Harley-Davidson UL/Panhead/Knucklehead 1939-73 WL/WLA/WLC/Servi-car
$27.07

Colony #2310-5 Oversized Foot Brake Lever Stud 23/32" OD 1939-1957 Harley-Davidson UL/Panhead/Knucklehead 1939-1973 WL/WLA/WLC/Servi-car
1 review $27.07

Colony #2519-2 Front Axle Smooth Covers 1991-2003 Harley-Davidson Dyna 1988-2007 Sportster - Chrome Plated
1 review $27.50

Colony #2436-10 #2438-5 Gas Tank Pike Nut Mounting Kit 1991-Up Harley-Davidson Dyna - Chrome Plated
1 review $27.23

Colony #2215-4 Swing Arm Pivot Hex Bolts 1984-1999 Harley-Davidson Softail - Chrome Plated
3 reviews $27.07

#2373-1 Fork Tube Bolt OEM 45756-59 Harley Superglide 71-72 K XL 52-72 — Colony #2373-1 Fork Tube Cap/Bolt 1971-1972 Harley-Davidson Superglide 1952-1972 K/XL - Chrome Plated
1 review $26.07

Colony #2506-5 Brake Shell Dowel Pin Set 1937-1972 Harley-Davidson Big Twin 1937-1952 45's
$25.30

Colony #2203-8 Safety Guard Mounting Kit 1937-1947 Harley-Davidson Big Twins 1955-1957 Panhead - Parkerized
$25.05

Colony #2401-15 Transmission Side Cover Allen Screw Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$24.72

Colony #2412-2 Crank Pin Nut Set 1954-E1981 Harley-Davidson 61"/80"
$32.00

Colony #2543-10 Circuit Breaker to Coil Wire Assembly 1949-1964 Harley-Davidson Twins
$24.20

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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