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 #2950-1 Lower Brake Cable Clamp 1940-1952 Harley-Davidson 45s & Servi-car - CAD Plated
$8.80

Colony #2947-1 Cylinder Bracket for Aluminum Heads 1936-1952 Harley-Davidson WL 45 1936-1973 Servi-car - Chrome Plated
$42.00

Colony #2946-1 Cylinder Bracket for Aluminum Heads 1936-1952 Harley-Davidson WL 45 1936-1973 Servi-car - CAD Plated
$37.00

Colony #2936-2 Clutch Adjusting Hole Filler Cap Allen Style 1985-1990 Harley-Davidson XLH - Chrome Plated
$36.20

Colony #2885-24 Valve Spring Cover Set Plated 1930-1936 Harley-Davidson VL - CAD Plated
$198.00

Colony #2883-3 Front Brake Cable Adjusting Screw 1949 Harley-Davidson Big Twins - CAD Plated
$22.00

Colony #2882-2 Rear Axle Adjusting Screw Kit Hex 2006-Up Harley-Davidson Dyna - Chrome Plated
$14.52

Colony #2869-1 Rear Axle Spacer 1938-1952 Harley-Davidson 45s/Solo - Chrome Plated
$22.00

Colony #2858-6 Grease Fitting OEM #9853 90 degree Harley-Davidson - 6 pack - Parkerized
$16.34

Colony #2854-6 Upper Engine Allen Mounting Kit 1984-1999 Harley-Davidson Softail - Chrome Plated
$13.92

Colony #2848-8 Batwing Fairing Spotlight and Turn Signal Bracket Mounting Kit 1996-Up Harley-Davidson - Chrome Plated
$16.34

Colony #2820-2 Brake Cable Lubricator 1930-1938 Harley-Davidson All Models
$30.04

Colony #2819-8 Horn Terminal Board Kit 1942-1946 Harley-Davidson All Models
$30.00

Colony #2814-18 Top of Tank Screw and Washer Kit 1918-1952 Harley-Davidson - Parkerized
$30.04

Colony #2811-13 Instrument Panel Light Switch Kit 1936-1945 Harley-Davidson Big Twin/45s - CAD Plated
$40.70

Colony #2804-2 Front Brake Cable Sleeve Adjuster and Nut 1928-1940 Harley-Davidson All Models - Parkerized
$15.52

Colony #2802-2 Front Brake Cable Sleeve Adjuster and Nut 1928-1940 Harley-Davidson All Models - Chrome Plated
$17.14

Colony #2798-3 Starter Crank Clamp Bolt 1929-1943 Harley-Davidson 45 1926-34 Singles1932-59 Servi-car - Chrome Plated
$10.29

Colony #2797-3 Starter Crank Clamp Bolt 1929-1943 Harley-Davidson 45 1926-34 Singles1932-59 Servi-car - Parkerized
$12.10

Colony #2795-8 Handlebar Lever and Switch Housing Mount Kit Acorn 2004-Up Harley-Davidson Sportster - Chrome Plated
$20.27

Colony #2792-3 Starter Crank Clamp Bolt 19441952 Harley-Davidson W Models - Parkerized
$12.10

Colony #2789-15 Horn Terminal Board Kit 1942-1952 Harley-Davidson WLA/WLC/XA
$30.00

Colony #2788-16 Motor Case Kit 1929-1939 Harley-Davidson 45s
$56.10

Colony #2785-2 Speedometer Drive Block-Off Plug 1952-1956 Harley-Davidson K/KH - Chrome Plated
$17.14

Colony #2782-4 Springer Spring Rod Kit 1938-1939 Harley-Davidson 45s
$42.63

Colony #2776-9 Headlight Bracket Mount Kit 1936-1948 Harley-Davidson Big Twin 1940-1957 45s - Chrome Plated
$24.20

Colony #2769-4 Kick Starter Pedal Mounting Kit 1917-1941 Harley-Davidson - Parkerized
$14.30

Colony #2768-10 Front Safety Guard Mounting Kit 1932-1973 Harley-Davidson 45s - Chrome Plated
$29.78

Colony #2750-4 Handlebar Bolt Kit 1937-1939 Harley-Davidson 45s - Parkerized
$9.68

Colony #2741-2 Clutch Tension Adjusting Nut and Lockwasher Undersized 1936-1940 Harley-Davidson Big Twins - Parkerized
$31.63

Colony #2740-2 Left Bearing End Oil Slinger 1939-1973 Harley-Davidson 45s
$16.94

Colony #2731-2 Seat Bar Clevis Pin Kit 1912-1933 Harley-Davidson - Parkerized
$6.05

Colony #2726-2 Pike Nut Spike Rear Axle Covers 2008-2012 Harley-Davidson Sportster - Chrome Plated
$54.14

Colony #2725-2 Rear Axle Covers Harley-Davidson 2008-2012 Sportster - Chrome Plated
$31.13

Colony #2722-20 Valve Spring Cover Kit 1942-1973 Harley-Davidson 45s - Parkerized
$105.60

Colony #2721-20 Valve Spring Cover Kit 1942-1973 Harley-Davidson 45s - Chrome Plated
$127.60

Colony #2718-11 Windshield Side Member Mount Kit 1924-1967 Harley-Davidson Sidecars - Parkerized
$49.50

Colony #2709-24 Motor Mounting Kit Upper and Lower Allen 2009-Up Harley-Davidson FLT - Chrome Plated
$31.90

Colony #2707-5 Linkert Low Speed Needle Valve 1933-1947 Harley-Davidson 1 inch Carburetors
$25.30

Colony #2689-10 Oil Pan Mounting Kit Acrons 2006-Up Harley-Davidson Dyna - Chrome Plated
$33.00

Colony #2688-6 Transmission Shifter Cover Screw Acorn Mounting Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
$21.78

Colony #2687-13 Transmission Side Cover Screw Acorn Mounting Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
$42.19

Colony #2686-18 Primary Cover Allen Screw Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
$58.30

Colony #2678-2 Gear Box Grease Tube and Fitting Kit 1926-1929 Harley-Davidson 61"/74" - Nickel Plated
$18.15

Colony #2653-5 Jiffy Stand Leg Bracket Mounting Kit 1930-1952 Harley-Davidson 45 Solo 1930-1936 VL - Parkerized
$14.52

Colony #2649-9 Top Motor Mount Hardware Kit 1936-1947 Harley-Davidson Big Twin - Parkerized
$15.13

Colony #2648-9 Top Motor Mount Hardware Kit 1936-1947 Harley-Davidson Big Twin - CAD Plated
$15.13

Colony #2646-1 Oversized Rear Axle Sleeve Nut 1930-1972 Harley-Davidson Big Twins - Parkerized
$4.76

Colony #2645-1 Oversized Rear Axle Sleeve Nut 1930-1972 Harley-Davidson Big Twins - CAD Plated
$4.76

Colony #2635-2 Fork Rocker Studs Towbar 1940-1948 Harley-Davidson Big Twins1940-1957 Servi-car
$55.00

Colony #2630-8 Front Crash Bar Mounting Kit 1951-1954 Harley-Davidson Big Twins - Chrome Plated
$6.96

Colony #2626-18 Rear Fender Support Mounting Kit 1952-1956 Harley-Davidson K/XL - CAD Plated
$24.75

Colony #2621-5 Axle Extension Nut Kit 1930-1967 Harley-Davidson Sidecars - Parkerized
$25.30

Colony #2607-3 Footboard Mounting Stud 1925-1928 Harley-Davidson OEM #2950-25 - Parkerized
$16.50

Colony #2606-3 Footboard Mounting Stud 1914-1928 Harley-Davidson OEM #2949-14 - Parkerized
$18.70

Colony #2578-4 Top Motor Mount Hardware Kit 1948-1951 Harley-Davidson Big Twins - Parkerized
$11.20

Colony #2572-1 Sprocket and Pinion Shaft Nut 1981-1985 Harley-Davidson Sportster
$12.10

Colony #2571-2 Crank Pin Nut Set 1983-1999 Harley-Davidson Big Twins
$29.00

Colony #2568-24 Spotlight Hardware and Rebuild Kit 1938-1961 Harley-Davidson - CAD Plated
$45.00

Colony #2565-3 Rear Brake Caliper Anchor Arm Bolt Kit 1981-1985 Harley-Davidson Big Twins - CAD Plated
$13.20

Colony #7922 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1991-1993 Sportster - Chrome Plated
$196.98

Colony #7919 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1986-1990 Sportster - Chrome Plated
$251.64

Colony #7918 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1985-1986 Big Twin Evo 5 speed - Chrome Plated
$279.88

Colony #7917 Complete Show Bike Kit Acorn Hardware Harley-Davidson Evo 4 Speed - Chrome Plated
$240.78

Colony #7916 Complete Show Bike Kit Acorn Hardware Harley-Davidson 1979-1984 FLT - Chrome Plated
$414.58

Colony #3060-5 Foot Clutch Lever Friction Disc Kit 1936-1940 Harley-Davidson Knucklehead 1938-1952 45 Solo 1938-1946 Servi-car - Parkerized
$37.39

Colony #3035-5 Top Motor Mount Hardware 1932-Up Harley-Davidson 45s - Parkerized
$10.37

Colony #3018-1 Clutch Spring Tension Adjusting Nut 1940 Harley-Davidson WLA - Parkerized
$12.10

Colony #3001-5 Rear Brake Switch Pull Kit 1936-1952 Harley-Davidson 45s - CAD Plated
$31.89

Colony #1025-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 2007-up Softail - Chrome Plated
$274.95

Colony #1024 Complete Show Bike Kit Allen Hardware Harley-Davidson 2007-2008 FLT - Chrome Plated
$219.15

Colony #1023-P Complete Show Bike Kit Smooth Allen Hardware Harley-Davidson 2006-up Dyna - Chrome Plated
$284.24

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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