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

James Gaskets Primary Cover Gasket & Seal Kit 1977-1990 Harley-Davidson XL
$30.70

Lowbrow Customs Solo Seat Springs - Barrel Style - 2 inch Chrome
28 reviews $24.55

British Standard Lucas Style Tail Light
20 reviews $27.24

Colony #9696-18 Saddle to Seat Tee Mounting Kit 1934-1980 Harley-Davidson All Models (Except FX/XL) - Parkerized
5 reviews $35.00

Kustom Tech Seventies 1 inch Clutch Lever - Polished Aluminum
5 reviews $244.44

Lowbrow Customs Rocker Box Oil Pressure Gauge Adapter Fitting - Chrome - 1971 - Up Harley-Davidson Shovelhead, 1971 - 1985 Sportster
9 reviews $30.51

Colony #7142-4 Knucklehead Type Rocker Arm Shaft End Plug - 1971-1985 Harley-Davidson Shovelhead 1971-85 Sportster - Chrome Plated
7 reviews $34.85

Colony #8321 CHR Complete Stock Hardware Kit - 1977-1980 Harley-Davidson Sportster - Chrome Plated
1 review $243.94

Drag Specialties LED Handlebar Marker Lights - Black - Smoke Lens
2 reviews $121.85

Lowbrow Customs PVC Spacer Kit For Extended 41mm Fork Tubes
$14.26

Cycle Standard 1/4 inch NPT Mini Petcock 90 degree Mini Ball Valve
29 reviews $21.99

Cycle Standard Keihin Carburetor Rebuild Kit
8 reviews $24.11

British Standard Clutch Plates - Fiber - for Triumph / BSA Motorcycles
24 reviews $80.35

Cycle Standard 22mm Petcock Harley-Davidson Style - Chrome - Right Hand Outlet
18 reviews $40.05

Lowbrow Customs 7mm Cloth 90 Degree Spark Plug Wire Sets - Satin Black
6 reviews $30.02

Cycle Standard Crocker Style LED Tail Light - Brass
$120.00

Prism Supply Co. Bristol Breather - S&S Super E/G Carburetor - Polished
$60.00

Custom Dynamics Micro Bullet Turn Signals - Black - Red
2 reviews $60.00

Marion Metalworks Universal Headlight Mounting Bracket/Eyebrow Delete
18 reviews $60.00

Lowbrow Customs Clutch / Brake Cable Clamp - Aluminum - for 1 inch Frame Tubing
4 reviews $20.00

Arlen Ness Big Sucker Stage 1 Air Filter Kit - Chrome - 1988-2020 Harley-Davidson XL
1 review $240.00

Monster Craftsman Weld On Tensioner Single Sided Mount Black Powell Wheel
$119.99

Prism Supply Co. Single Wire Tail Light Magic Box
$39.99

Prism Supply Co. 3/8 inch NPT Petcock - Stainless Steel
3 reviews $119.95

Goodridge 30342TC-CL Universal Braided Stainless Brake Line - 42" - Clear Coated
1 review $79.95

Gasbox 4 Speed Transmission Mounting Plate for 1965 - 1979 Harley-Davidson Big Twins OEM #47698-65
2 reviews $59.95

Biltwell Whiskey Throttle Tube - Black - 1 inch
15 reviews $59.95

Goodridge Universal Braided Stainless Brake Line - 18" - Ebony
$29.95

Cycle Standard 1/4 inch NPT Petcock Black - 90 Degree
9 reviews $26.62 $36.74

Lowbrow Customs Pursuit Shifter Peg for Harleys - Black Aluminum
44 reviews $34.21

ODI Vans/Cult V-Twin Motorcycle Grips by ODI - White - 1 inch
8 reviews $19.95

Colony #8618-20 Big Bore Headbolt & Washer Kit 1949-Up Harley-Davidson Panhead/Shovelhead - Black
4 reviews $47.80

Lowbrow Customs Regulator Mounting Bracket for your Unit Triumph
15 reviews $26.41

Lowbrow Customs Brass Float Bowl Drain Plug for Amal Carburetors
27 reviews $15.82

Wassell 930 Left Side 30mm Concentric Carburetor Triumph BSA Norton
1 review $235.94

Cycle Standard Mikuni HSR 42/45 Carburetor Adapter for CV Air Cleaners
6 reviews $46.95

Cycle Standard Chrome Dual Cable Throttle Assembly with Black Grips - 1 inch OEM #56392-77
15 reviews $33.51

Colony #2333-2 Rubber Mount Studs Harley-Davidson OEM #62563-65
7 reviews $11.17

Goodridge P592-03C Straight 3/8 inch/10mm Banjo Fitting - Stainless Steel
8 reviews $17.95

Mooneyes Cast Aluminum MOON Oil Tank Mounting Brackets
2 reviews $116.67

Cycle Electric Rectifying Regulator CE-602 - 2004-2005 Harley-Davidson Dyna Models
$232.89 $249.30

Lowbrow Customs 39mm Low Profile Fork Caps - Brass

14 $58.02

Cycle Standard Translucent Fuel Line - Clear - 1/4 inch ID
28 reviews $13.64

Lowbrow Customs Aluminum Gas Filler Cap - Vented
6 reviews $33.02

DP Brakes Full Clutch Plate Kit 1991-2022 Harley-Davidson Sportster XL
$230.95

S&S Cycle H-Grind Camshaft - 1948-1969 Harley-Davidson Big Twin
1 review $230.36 $255.95

Prism Supply Co. Darlington Air Cleaner - CV Carburetor - Polished
$229.99

Kustom Tech Classic 1 inch Brake Lever Polished Aluminum
1 review $229.71

Lowbrow Customs Knurled Grips - Black - 1 inch
67 reviews $25.50

Cycle Electric Rectifying Regulator CE-601-07 - 2007 Harley-Davidson Softail Models
$229.11 $245.25

Bates Kill Bill Battery Switch - Black Knob
9 reviews $22.88

Cycle Electric Stator CE-8590 for 1984-1990 Harley-Davidson Sportster OEM# 29967-84A
$114.08 $122.11

ODI Vans V-Twin Lock-On Cable Throttle Grips by ODI - Graphite/Gunmetal - 1"
4 reviews $75.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 12" T-Bar Handlebars 07-11 FXD w/o ABS

$227.66 $252.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 14" Ape Hanger Handlebars 00-06 FLST/C/F/N

1 $227.66 $252.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 14" Ape Hanger Handlebars H-D 1999-05 FXD
2 reviews $227.66 $252.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 16" Ape Hanger Handlebars 2004-2006 Harley-Davidson Sportsters
$227.66 $252.95

Lowbrow Customs Weld-In Gas Tank EFI Plate for Harley-Davidson Sportster Fuel Pump
$45.40

Andrews J-Grind Camshaft - L1977-1984 Harley-Davidson Shovelhead
$226.76 $251.95

Lowbrow Customs Blade Levers - Polished - 1996 - 2003 Harley Davidson Sportsters and 1996 - 2017 Dyna / Softail / Touring Models
31 reviews $45.25

Colony #1025 Complete Show Bike Kit Allen Hardware Harley-Davidson 2007-up Softail - Chrome Plated
$225.80

Cycle Standard Replacement Dished Sprocket - Chrome - 47 Tooth - 1973-1985 Harley-Davidson Big Twin 1979-81 XL
$75.05

Airspeed Cycles Z Bar Handlebars - 1 inch - 6 inch Rise - Stainless Steel
$225.00

Airspeed Cycles Z Bar Handlebars - 1 inch - 4 inch Rise - Stainless Steel
$225.00

After Hours Choppers Stainless Steel Ratchet Top Shifter - 15 Degree Lay Back - Raw
$225.00

Gasbox Front Exhaust Pipe 1966-1969 Harley-Davidson Shovelhead - Chrome - OEM #65443-66
2 reviews $75.00

Bates Baja Skid Plate for 2004 & Up Harley-Davidson Sportsters - Black
1 review $224.99

Cooper Smithing Co. Ribbed Handmade Steel Fender - for 16 inch Tires
12 reviews $224.95

Lowbrow Customs Domed Steel Motorcycle Oil Tank for H-D Sportster Big Twin and Universal Choppers
23 reviews $224.94

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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