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 #2469-8 Transmission to Motor Mount Acorn Kit 2007-Up Harley-Davidson Dyna Softail/FLT - Chrome Plated
$28.97

Colony #2467-1 Linkert Carburetor Venturi Indian 80 Chiefs and Bonneville Motors M-350 M-352 M-Bonn
$40.61

Colony #2465-1 Linkert Carburetor Venturi 1941-1948 74 Indian Chiefs M-6 M-341 M-343 M-344
$40.61

Colony #2461-3 Gas Tank Clip Screw Set 1910-1917 Harley-Davidson All Models - Nickel Plated
$16.70

Colony #2458-8 Tool Box Mounting Kit 1935-1936 Harley-Davidson 74" Twins 1931-1934 45s & Singles - Chrome Plated
$26.57

Colony #2454-36 Pushrod Cover Complete Kit Billet Alloy 1984-Up Harley-Davidson Big Twin Evo - Chrome Plated
$225.17

Colony #2453-12 Pushrod Cover Kit Billet Alloy 1984-Up Harley-Davidson Big Twin Evo - Chrome Plated
$177.10

Colony #2451-17 Motor Case Kit 1952-1956 Harley-Davidson K Model - CAD Plated
$34.10

Colony #2448-2 Axle Adjuster Covers 2005-Up Harley-Davidson Sportster - Chrome Plated
$31.63

Colony #2435-16 Head Bolt Set 1940-1951 Harley-Davidson WR/WLDR - Parkerized
$109.62

Colony #2434-1 Spark Plug Cable Bracket 1937-1973 Harley-Davidson 45s & Sidevalves - Parkerized
$16.50

Colony #2421-3 Intake Manifold Pipe Mounting Screws 1921-1923 Harley-Davidson JD 1924-1929 J/JD - CAD Pated
$12.53

Colony #2420-3 Intake Manifold Pipe Mounting Screws 1915-1923 Harley-Davidson J Model - Nickel Plated
$12.53

Colony #2418-1 Transmission Oil Pan Plug OEM #45890-99 FLT Dyna - Chrome Plated
$3.49

Colony #2417-2 Cone Head Riser Bolt Covers Harley-Davidson - Chrome Plated
$29.10

Colony #2416-4 Cone Head Riser Bolt Covers 1/2-13 x 2-3/4 bolts 1997-Up Harley-Davidson FXST/FXSTB/FXSTC/FXSTD 1993-2000 FXR 1991-Up Dyna - Chrome Plated
$41.75

Colony #2411-2 Crank Pin Nut Set 1941-1953 Harley-Davidson 74" Big Twins
$32.00

Colony #2408-2 Rear Axle Covers Smooth 2013-Up Harley-Davidson Sportster 2008-Up Dyna & Softail - Chrome Plated
$33.00

Colony #2404-6 Transmission Shifter Cover Allen Screw Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$8.70

Colony #2403-22 Motor Mounting Kit Upper and Lower Allen 2007-Up Harley-Davidson - Chrome Plated
$50.60

Colony #2400-12 Transmission Oil Pan Allen Screw Mounting Kit 2007-UpHarley-Davidson FLT - Chrome Plated
$17.40

Colony #2392-2 Front Axle Smooth Covers 2000-2007 Harley-Davidson Touring 2004-2007 Dyna - Chrome Plated
$31.63

Colony #2388-5 Front Axle Nut Spacer Washer Kit 2000-Up Harley-Davidson FLSTS - Chrome Plated
$50.60

Colony #2387-5 Front Axle Nut Spacer Washer Kit 2007-Up Harley-Davidson FLSTF - Chrome Plated
$43.45

Colony #2382-24 Transmission Side Cover Mounting Kit 1915-1930 Harley-Davidson Twins - Parkerized
$28.47

Colony #2377-36 Transmission Top Cover Mounting Kit 1915-1930 Harley-Davidson Twins - Nickel Plated
$45.54

Colony #2375-1 Pinion Gear Shaft Nut 1981-1989 Harley-Davidson Big Twins
$12.10

Colony #2362-3 Pike Nut 12mm Brake Line Banjo Bolt 7/16-24 thread Replaces OEM #41739-84A - Chrome Plated
$15.64

Colony #2361-3 Pike Nut 12mm Brake Line Banjo Bolt 2004-Up Harley-Davidson Sportster - Chrome Plated
$15.64

Colony #2359-3 Pike Nut 10mm Brake Line Banjo Bolt 2004-Up Harley-Davidson Sportster - Chrome Plated
$14.16

Colony #2352-1 Foot Clutch Lever Bracket Spring Stud 1932-1936 Harley-Davidson VL
$9.75

Colony #2350-2 Foot Clutch Lever Pivot Shaft 1941-1964 Harley-Davidson Big Twins
$20.88

Colony #2345-6 Transmission Shifter Cover Allen Screw Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
$8.56

Colony #2344-10 Oil Pan Mounting Allen Screw Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
$14.89

Colony #2340-1 Linkert Carburetor Venturi 15/16 inch OEM #27364-41
$40.61

Colony #2337-5 Front Axle Nut Spacer Washer Kit 2006-2007 Harley-Davidson Dyna FXDWG - Chrome Plated
$43.45

Colony #2328-1 Linkert Carburetor Venturi 7/8 inch OEM #27360-29
$40.61

Colony #2311-2 Pike Nut Fork Tube Cap/Plug 1978-Up Harley-Davidson FL/FXWG/Softail - Chrome Plated
$27.50

Colony #2309-6 Foot Brake Lever Stud Oversized 23/32" OD 1936-1938 Harley-Davidson
$27.07

Colony #2261-2 Pike Nut Axle Adjuster Covers 1993-2004 Harley-Davidson Sportster - Chrome Plated
$54.14

Colony #2257-4 Rear Axle Nut Spacer Washer Kit 2005 Harley-Davidson Sportster - Chrome Plated
$43.45

Colony #2225-8 Lifter Base Screw Acorn Screw Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$25.71

Colony #2224-8 Lifter Base Allen Screw Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$11.90

Colony #2221-24 Primary Cover Acorn Nut Screw Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$61.36

Colony #2218-8 Motor Case Acorn Nut Mounting Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$32.12

Colony #2210-4 Valve Stem Cap and Locknut Kit for Harley-Davidson Motorcycles - Chrome Plated
$17.88

Colony #2204-8 Safety Guard Mounting Kit 1937-1947 Harley-Davidson 61"/74" 1955-1957 Panhead - Chrome Plated
$29.78

Colony #2187-11 Front Crash Bar Mounting Kit 1958-1969 Harley-Davidson FL - CAD Plated
$8.56

Colony #2186-11 Front Crash Bar Mounting Kit 1958-1969 Harley-Davidson FL - Chrome Plated
$9.31

Colony #2182-4 Handlebar Grip Retainer Kit 1950-1959 Harley-Davidson Lightweights - Chrome Plated
1 review $31.90

Colony #2179-7 Windshield Mounting Allen Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$7.45

Colony #2176-8 Frame Assembly Allen Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$11.90

Colony #2173-3 Sprocket Cover Mounting Allen Kit 2002-2005 Harley-Davidson VRSC - Chrome Plated
$4.47

Colony #9998-3 Front Axle Nut Spacer Kit Grooved 1997-1999 Harley-Davidson FXSTS - Chrome Plated
$33.31

Colony #9995-4 Front Axle Nut Spacer Kit Smooth 1997-1999 Harley-Davidson FLSTC - Chrome Plated
$31.87

Colony #9994-4 Front Axle Nut Spacer Kit Grooved 1997-1999 Harley-Davidson FLSTC - Chrome Plated
$33.31

Colony #9992-5 Front Axle Nut Spacer Kit Grooved 1997-1999 Harley-Davidson FXST/FXSTC/FXSTB - Chrome Plated
$46.35

Colony #9991-5 Front Axle Nut Spacer Kit Smooth 1995-1996 Harley-Davidson FXDWG - Chrome Plated
$43.45

Colony #9968-12 Pushrod Covers 1999-Up Harley-Davidson Twin Cam- Chrome Plated
$66.63

Colony #9958-19 Primary Cover Mounting Kit Allen 1999-Up Harley-Davidson FLT - Chrome Plated
$49.25

Colony #9956-18 Motor Case Mounting Kit Allen 1999-Up Harley-Davidson Twin Cam/Dyna/FLT 2000-Up Softail - Chrome Plated
$20.85

Colony #9955-27 Motor Case Mounting Kit Acorn 1999-Up Harley-Davidson Twin Cam/Dyna/FLT 2000-Up Softail - Chrome Plated
$36.20

Colony #9953-10 Point Cover Mounting Acorn Nut Kit 199-Up Harley-Davidson Twin Cam Dyna/FLT 2000-Up Softail - Chrome Plated
$15.14

Colony #9952-11 Transmission Shifter Cover Mounting Kit Allen 1998-2006 Harley-Davidson FLT/Softail - Chrome Plated
$11.90

Colony #2403-22-P Upper and Lower Motor Mounting Kit Smooth Allen 2007-2008 Harley-Davidson FLT - Chrome Plated
$56.93

Colony #2402-18-P Primary Cover Smooth Allen Screw Kit 2007-Up Harley-Davidson FLT - Chrome Plated
$46.18

Colony #2270-4-P Passenger Left and Right Footrest Mounting Kit Smooth 2004-Up Harley-Davidson XL - Chrome Plated
$9.68

Colony #2269-7-P Footpeg Support Bracket Mounting Kit Smooth Allen 2004-Up Harley-Davidson Sportster - Chrome Plated
$14.16

Colony #2224-8-P Lifter Base Smooth Allen Screw Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$17.88

Colony #2217-8-P Motor Case Smooth Allen Screw Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$27.07

Colony #2175-4 Upper and Lower Front Fork Bracket Allen Mounting Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$6.70

Colony #2007-6-P Air Cleaner Mounting Kit Smooth Allen 1978-1983 Harley-Davidson Big Twins - Chrome Plated
$5.92

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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