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

Drag Specialties Replacement Rear Fender 2009-13 Harley-Davidson FLHT/FLHR/FLTR
$152.95

Drag Specialties Replacement Rear Fender 1982-94 Harley-Davidson FXR
1 review $157.95

Drag Specialties Replacement Rear Fender 1979-81 Harley-Davidson Sportster XL
1 review $107.95

Drag Specialties Replacement Rear Fender 1984-96 Harley-Davidson FXST
$173.95

Drag Specialties Replacement Rear Fender 1980-84 Harley-Davidson FXWG
$161.95

Drag Specialties Replacement Rear Fender 1986-97 Harley-Davidson FLST/FLSTC - Smooth Style
1 review $176.95

Goodridge 30319TC-CL - Universal Braided Stainless Brake Line - 19" - Clear Coated
$62.95

Goodridge 30317TC-CL - Universal Braided Stainless Brake Line - 17" - Clear Coated
$61.95

Goodridge Universal Braided Stainless Brake Line - 15" - Clear Coated
$20.95

Goodridge 30312TC-CL - Universal Braided Stainless Brake Line - 12" - Clear Coated
1 review $57.95

Drag Specialties Replacement Front Fender 41MM Front Ends Replaces OEM #59924-80A
1 review $87.95

Drag Specialties Replacement Front Fender 2012-17 Harley-Davidson FLS
1 review $152.95

Drag Specialties Replacement Front Fender 2000-13 Harley-Davidson FLT/FLHT/FL Trikes
$170.95

Drag Specialties Replacement Front Fender 2014-20 Harley-Davidson FLHX/FLTRX/FLTRU/FLTRK - Smooth Style
1 review $159.95

James Gaskets Complete Rocker Cover Gasket Kit 1984-1991 Harley-Davidson Evo Big Twin
$88.41

James Gaskets Top End Gasket Kit 1957-1971 Harley-Davidson Sportster
2 reviews $37.10

Colony #8703-2 Oil Pump Screen Check Relief Plug 1981-Up Harley-Davidson Big Twins - Chrome Plated
$12.34

Colony #7614-2 Intake Manifold Nut Kit 1940-1954 Harley-Davidson OHV 74's 1953-1956 K/KH - CAD Plated
$30.42

Colony #3675-10 Knurled Allen Sprocket Bolts 1993-1996 Harley-Davidson Big Twins 1997-1999 Dyna/Touring - Chrome Plated
$24.85

Colony #3673-10 Allen Sprocket Bolts 1973-Up Harley-Davidson Big Twins/XL - Chrome Plated
$20.63

Colony #3275-2 Pike Nut Front Axle Cover 2001-2011 Harley-Davidson Softail Springer & Heritage Springer - Chrome Plated
2 reviews $54.14

Colony #3332-1 Stem Crown Nut 1936-1938 Harley-Davidson Big Twin Springer - Chrome Plated
$63.80

Colony #3236-1 Stem Crown Nut 1936-1938 Harley-Davidson Big Twin Springer
$55.00

Colony #3229-5 Circuit Breaker Post Rebuild Kit 1930-1948 Harley-Davidson Al lModels
$17.86

Colony #3220-6 Rear Fender Frame Clamp Bolt 1936-1957 Harley-Davidson Big Twins - Chrome Plated
$49.50

Colony #3216-2 Clutch and Brake Lever Bushings 1941-1964 Harley-Davidson
$6.05

Colony #3209-4 Lifter Base Screw Kit 1957-1985 Harley-Davidson Sportster - CAD Plated
1 review $10.65

Colony #3273-20 Valve Spring Cover Kit 1931-1941 Harley-Davidson 45's - Chrome Plated
$127.60

Colony #3057-4 Lower Valve Spring Cover Kit 1952-1956 Harley-Davidson K Models
$88.00

Colony #3062-3 Brake Shoe Pivot Stud Kit 1941-1952 Harley-Davidson 45's - Parkerized
$18.15

Colony #3058-10 Rear Motor Mount & Sprocket Cover Mounting Kit 1983-1985 Harley-Davidson XL - Zinc Plated
$27.50

Colony #3051-1 Oversized Drain Plug 1965-1984 Harley-Davidson FL 1971-1984 FX Chain Housing 1967-1992 XL Crankcase - Zinc Plated
$7.26

Colony #3032-4 Cam Follower & Retainer Kit 1952-1979 Harley-Davidson FL/FLH 1971-1979 FX
$36.30

Colony #2735-1 Oil Line Fitting Replaces OEM #63533-41 - CAD Plated
$4.24

Colony #2697-1 Linkert High Speed Needle 1952-1956 Harley-Davidson K/KH - CAD Plated
$22.00

Colony #2348-2 Luggage Carrier Fender Mounting Studs 1942-Up Harley-Davidson WL/WLA/WLC - Parkerized
$18.15

Colony #2197-1 3/4 inch ID Axle Spacer 3/8 inch Thick - Chrome Plated
$6.70

Colony #1028-P Complete Show Bike Kit Polished Allen 2017-Up Harley-Davidson Touring Models - Chrome Plated
$245.03

Colony #1027-P Complete Show Bike Kit Polished Allen 2007-Up Harley-Davidson VRSC - Chrome Plated
$173.38

Drag Specialties Small Radius Laydown 3 Bolt Style License Plate Mount Assembly - Flat Black
1 review $93.61

Colony #3690-16 Plain Head Lower Motor Mount Kit 1936-1957 Harley-Davidson OHV Big Twins - Parkerized
$40.70

Colony #3687-15 Lower Motor Mount Kit 1937-1947 Harley-Davidson Side Valve Big Twins - Parkerized
$39.88

Colony #3682-16 Lower Motor Mount Kit 1958-1965 Harley-Davidson OHV Big Twins - Chrome Plated
$33.55

Colony #3681-16 Lower Motor Mount Kit 1958-1965 Harley-Davidson OHV Big Twins - Parkerized
$30.80

Colony #3680-16 Lower Motor Mount Kit 1936-1957 Harley-Davidson OHV Big Twins - CAD Plated
$40.70

Colony #3679-16 Lower Motor Mount Kit 1936-1957 Harley-Davidson OHV Big Twins - Chrome Plated
$44.28

Colony #3573-10 Front Disc Brake Rotor Screw Set 2002-Up Harley-Davidson VRSC - Zinc Plated
2 reviews $23.65

Colony #3572-5 Front Disc Brake Rotor Screw Set 2006-Up Harley-Davidson Dyna - Zinc Plated
$13.01

Colony #3554-4 Gas Tank Mounting Kit 2008-Up Harley-Davidson FLT 2017-Up M8 - Chrome Plated
$6.66

Colony #3552-6 Clutch Cover Mounting Kit 2004-Up Harley-Davidson XL - Chrome Plated
$8.47

Andrews V4 Camshafts - 1986-1990 Harley-Davidson Sportster XL
$454.46 $504.95

S&S Cycle Quickee Adjustable Pushrod Set With Chrome Covers- 2004-2021 Harley-Davidson Sportster XL
$294.26 $326.95

Andrews A2 Camshaft - L1977-1984 Harley-Davidson Shovelhead
2 reviews $226.76 $251.95

Andrews A2 Camshaft - 1948-1969 Harley-Davidson Big Twin
$226.76 $251.95

Andrews N-Grind Camshaft - 1937-1947 Harley-Davidson Knucklehead
$231.26 $256.95

Andrews EV46 Camshaft - 1984-1999 Harley-Davidson Big Twin
$226.76 $251.95

Andrews N4 Camshafts - 1991-1999 Harley-Davidson Sportster XL 1994-99 Buell
$454.46 $504.95

Andrews N2 Camshafts - 1991-1999 Harley-Davidson Sportster XL 1994-99 Buell
$454.46 $504.95

S&S Cycle 500 Camshafts - 1991-2021 Harley-Davidson Sportster XL
$575.96 $639.95

James Gaskets Cam Change Gasket Kit - 1993-99 Harley-Davidson 80 inch Big Twin
$30.10

James Gaskets Cam Change Gasket Kit with Metal Cam Cover Gasket - 1993-99 Harley-Davidson 80 inch Big Twin
$36.14

James Gaskets Cam Change Gasket Kit - 1970-92 Harley-Davidson Big Twin
$30.09

S&S Cycle Mini Teardrop Stealth Air Cleaner - Black - 2001-2017 Harley-Davidson Twin Cam
$356.36 $395.95

S&S Cycle Mini Teardrop Stealth Air Cleaner - Chrome - 2001-2017 Harley-Davidson Twin Cam
$356.36 $395.95

S&S Cycle Mini Teardrop Stealth Air Cleaner - Black - 2007-Up Harley-Davidson Sportster XL
$356.36 $395.95

S&S Cycle Mini Teardrop Stealth Air Cleaner - Chrome - 2007-Up Harley-Davidson Sportster XL
$376.20

S&S Cycle Tear Drop Air Cleaner - Chrome - 1991-2006 Harley-Davidson Sportster XL
$356.36 $395.95

S&S Cycle Tear Drop Air Cleaner - Chrome - 1993-2009 Harley-Davidson Big Twin
1 review $356.36 $395.95

S&S Cycle 2.5 inch Velocity Stack for S&S Super E/G Carburetor
2 reviews $168.69 $183.95

S&S Cycle Super E Carburetor Kit 1991-2003 Harley-Davidson Sportster XL
3 reviews $729.73 $799.95

British Standard Triumph Unit 650/750 Finned Primary Cover - Polished - Replaces OEM #71-3555
2 reviews $559.96

British Standard Triumph Unit 650/750 Finned Primary Cover - Raw - Replaces OEM #71-3555
2 reviews $439.18

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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