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 #8605-16 Lifter Base Screw Kit Hex Head 1954-1974 Harley-Davidson Big Twin - CAD Plated
$20.57

Colony #2669-6 Clutch Foot Lever Mount Kit Oversized 1947-1973 Harley-Davidson Servi-car & WR
$20.35

Colony #3601-2 Buddy Seat Bar Mounting Plates 1936-1980 Harley-Davidson Big Twins - Parkerized
$20.35

Colony #2099-16 Lifter Base Phillips Screw Kit 1950-1953 Harley-Davidson Big Twin 1952-1956 K Models - Chrome Plated
$20.33

Colony #3666-13 Transmission Side Cover Allen Screw Kit 1987-2006 Harley-Davidson FX/FL/Softail 1991-2005 Dyna - CAD Plated
$20.32

Colony Axle / Wheel Spacer 2-3/16x3/4x.790 tapered Harley-Davidson #43623-00 — Colony #43623-00 Axle/Wheel Spacer 2-3/16x3/4x.790 Tapered
1 review $20.31

Colony #2144-1 Aluminum Primary Cover Filler Plug 1954-1970 Harley-Davidson Sportster
$20.31

Colony #9937-20-P Front Motor Mount Kit Smooth Chrome Allen Harley Dyna 91-up — Colony #9937-20-P Front Motor Mount Smooth Allen Kit 1991-Up Harley-Davidson Dyna - Chrome Plated
1 review $20.27

British Standard Rotor Key - Triumph Unit 650 750
3 reviews $10.13

Colony #2457-8 Tool Box Mounting Kit 1935-1936 Harley-Davidson 74" Twins 1931-1934 45's/Singles - Parkerized
$20.24

Cycle Standard Kickstand Spring 2002 & Up Harley-Davidson Dyna Models - Black - OEM #50057-02
9 reviews $10.09

Colony #2170-9-P Water Pump Cover Thermostat Smooth Allen Mounting Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
$20.11

Colony #8608-36 Rocker Box Nut Kit 1966-1983 Harley-Davidson Shovelhead - Chrome Plated
2 reviews $20.11

Colony #2477-10 Front Safety Guard Mounting Kit 1948-1950 Harley-Davidson 61"/74" Twins - Parkerized
$20.00

Colony #8894-9 Cam Cover Screw Kit 1952-1970 Harley-Davidson K/KH/XL/XLCH/XLH - Chrome Plated
$20.00

Lowbrow Customs Rotor Sprocket Pulley Spacer 1/16" Stainless Steel for 2000-later Harley Rear Wheel
$19.99

Lowbrow Customs Rotor Sprocket Pulley Spacer 1/16" Stainless Steel for 1984-1999 Harley Rear Wheel
$19.99

Prism Supply Co. Acorn Shift Knob
$19.99

Colony #2754-12 Front Brake Caliper Mounting Allen Kit 2008-Up Harley-Davidson Softail/Dyna - Chrome Plated
$19.97

Gasbox Stainless Steel Hardware Mounting Kit for 1958-1978 Harley-Davidson Sportster Style Gas Tanks on Gasbox Full Frames
1 review $19.95

Gasbox Lower Fender Mount For 4 Speed Transmission Plate
$19.95

Colony #8859-1 Seat Post Bushing 1929-Up Harley-Davidson 45 Singles 1930-1936 VL OEM ##3113-29
2 reviews $19.93

Colony #7804-6 Spark Plug Cable Packing Nut Kit 1927-1959 Harley-Davidson Coils
1 review $19.93

Colony #3770-4 1/2 x 5/16" x 5/16" Spacer Harley-Davidson OEM #67009-72 - 4 Pack
$9.90

Goodridge P822-03P3 90 Degree AN3 to 1/8 inch NPT Fitting - Stainless Steel
$4.95

Colony #2809-3 Clutch and Brake Hand Lever Clamp Bushing Kit 1949-1964 Harley-Davidson All Models - CAD Plated
$9.90

Colony #3529-7 Horn Trumpet Mount 1954-1964 Harley-Davidson Big Twins 1957-1964 Sportster
$19.67

Cycle Standard Throttle Idle Cable OEM #56309-96 Harley Sportster XL 1996-2001 - Blacked Out
3 reviews $19.52 $27.88

Colony #8941-3 Rocker Box Oil Feed Line Fittings 1942-1947 Harley-Davidson Knucklehead OEM #95-42 95-42A - CAD Plated
$19.51

Colony #3453-2 Rocker Plate Stud Spacer Nut 1926-1929 Harley-Davidson Singles/45 Twins 1930-1934 21" Singles - Parkerized
$9.68

Colony #3166-1 Timer Screw 1970-E1978 Harley-Davidson FL 1971-E1978 FX/XL - Zinc Plated
$9.68

Colony #3033-2 Rear Motor Mount Nut Kit 1962-1978 Harley-Davidson XL/XLH/XLCH
1 review $19.36

Colony #3492-2 Gas Tank Top Screw Bungs 1937-1952 Harley-Davidson 45's 1937-1973 Servi-car
$19.36

Colony #2343-13 Transmission Side Cover Allen Screw Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
$19.36

Colony #8788-11 Primary Cover Allen Screw Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
$19.36

Cycle Standard Model A Tail Light Mounting Bracket - Horizontal License Plate
16 reviews $19.33

Cycle Standard Reinforced Translucent Fuel Line - Red - 1/4 inch ID
4 reviews $19.33

Colony #3199-5 Parkerized Carburetor Support Bracket Harley Davidson 41-47 OHV Big Twin — Colony #3199-5 Carburetor Support Bracket Harley-Davidson 1941-1947 OHV Big Twins - Parkerized
$19.25

Colony #3375-3 Left Bearing Bushing Screw 1929-1936 Harley-Davidson 45"/74"/80" Twins/C Singles Twins
$19.06

Gasbox Replacement Tabs for Lowbrow Customs Weld-On Ironhead Hardtail Rear Frame Section for 1952-1981 H-D Sportster
$4.73

Cycle Standard Chrome Distributor Cover 1936-64 Harley-Davidson Big Twins K KH Sportster and 45 inch Twins
2 reviews $9.46 $12.93

Colony #9891-18 Gas Tank Mounting Kit 1937-1975 Harley-Davidson Big Twin 1972-1972 FX - Chrome Plated
3 reviews $18.88

Colony #9106-8 Rear Brake Caliper Anchor Arm Bolt Kit 1973-1983 Harley-Davidson FL/FX - Chrome Plated
$18.76

James Gaskets Replacement Float Bowl O-ring for 1988-1991 Harley-Davidson CV Carbs
$6.24

Colony #8783-8-P Cam Cover Smooth Allen Screw Kit 1971-1985 Harley-Davidson Sportster - Chrome Plated
1 review $18.62

Colony #8796-4 Handlebar Clamp Allen Screw Kit 1982-Up Harley-Davidson FX/XL - Chrome Plated
8 reviews $9.31

Colony #8405-2 Transmission Filler Cap/Dipstick 1985-1986 Harley-Davidson FLT 5 Speed - Chrome Plated
$18.34

Colony #8494-1 1937-1986 Harley-Davidson Big Twin Transmission & Sportster XL Motor Case Drain Plug OEM #707 - Chrome Plated
1 review $9.16

EMGO Universal Pod Air Filter 42mm
11 reviews $18.17

Colony #9515-2 Rear Axle Adjusting Screw 1993-1999 Harley-Davidson FXST OEM #47579-93 - Chrome Plated
1 review $18.16

Colony #2347-2 Luggage Carrier Fender Mount Studs 1926-1941 Harley-Davidson 45s - Parkerized
$18.15

Colony #2884-6 Magneto Adapter Plate Screw 1958-1962 Harley-Davidson XLCH - CAD Plated
$18.15

Colony #3259-1 Wire Clip 1924-1929 Harley-Davidson J/JD/DH 1930 VL/VC 1931-1932 Singles - Parkerized
1 review $18.15

Colony #3121-6 Carburetor Bowl Locknut CAD 1930-65 Harley Davidson Big Twins — Colony #3121-6 Carburetor Bowl Locknut 1930-1965 Harley-Davidson Big Twins - CAD Plated
$18.15

#3097-1 Transmission Adjuster Screw Support Strap Parkerized Harley Big Twins 1936-57 — Colony #3097-1 Transmission Adjuster Screw Support Strap 1936-1957 Harley-Davidson Big Twins - Parkerized
1 review $18.15

Colony #2894-7 Starter Crank and Kick Starter Pedal Mounting Kit 1941-1967 Harley-Davidson FL/FLH - Parkerized
1 review $18.15

Colony #9681-7 Generator Mounting Hardware Kit 1930-1957 Harley-Davidson Twins - Parkerized
$18.15

Colony #2983-2 4 inch Heavy Duty Solo Seat Springs - Made in USA - Chrome Plated
11 reviews $18.14

Colony #2358-4 Pike Nut Long Valve Stem Cap and Locknut Kit - 2 pack - Chrome Plated
$18.10

British Standard Petcock Straight Fuel Feed Pipes British Triumph BSA Norton OEM #82-3334
4 reviews $18.07

Drag Specialties Handlebar Plug for Throttle By Wire (TBW) Handlebars
$9.00

Cycle Craft #200 Main Jet - 1988-2006 Keihin CV Carburetor
$5.99

Colony #3663-10 Disc Rotor Allen Screw & Nut Kit 1979-1991 Harley-Davidson XL/FX (Spoked Wheel) - Chrome Plated
$17.88

Colony #9776-10 Handlebar Lever Mount & Master Cylinder Allen Screw Kit 1996-Up Harley-Davidson Dyna/Softail 1996-2007 FLT 1996-2003 XL - Chrome Plated
$17.88

Colony #2248-4 Handlebar Riser Hex Bolt Kit 1/2-13 x 3-1/2 - CAD Plated
$8.93

Colony #2245-4 Handlebar Riser Hex Bolt Kit 1/2-13 x 2-1/2 - CAD Plated
1 review $8.93

Colony #9814-16 Lifter Base Screw Kit 1/4-20 Harley-Davidson Aftermarket Case - Chrome Plated
1 review $17.69

Colony #2440-2 Crankcase Vent Fitting and Hose 1977-1980 Harley-Davidson Sportster - Zinc Plated
3 reviews $17.60

Colony #9714-1 Oversize Timing Oil Tank Plug Harley-Davidson - Parkerized
$8.80

Colony #8115-1 Timing Plug/Oil Tank Plug OEM #704 1952-1969 Harley-Davidson FL and XL - CAD Plated
3 reviews $8.80

Colony #9710-3 Oval Head Screw Kit 5/16"-24 Harley-Davidson - Parkerized
$8.78

Colony #8921-5 Transmission Shifter Cover Acorn Head Screw Kit 1987-Up Harley-Davidson Evo FX/FL/Softail - Chrome Plated
$17.52

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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