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

Sort by

Custom Motorcycle Parts CATEGORIES

Closeouts

Air Intake & Fuel Systems

Brakes

Drivetrain & Transmission

Electrical & Wiring

Engine

Exhaust

Fenders

Frame & Chassis

Gas tanks

Gauges & Instruments

Handlebars & Controls

License Plates

Lighting

Oil Tanks

Seats

Sissy Bars

Suspension

Tires & Tubes

Wheels & Wheel Components

BEST SELLING BRANDS

TOP Custom Motorcycle Parts

Gremlin Wiring The Sportster Treatment Custom Wiring Harness Kit 1994-1996 Harley-Davidson Sportster Models
15 reviews $249.95

Gasbox Gasbox "Lorain" Full Frame 1957-1985 Harley-Davidson Ironhead Sportsters
$1,499.00

Gasbox Gasbox "Lorain" Sportsters Full Frame for 1986-2003 Harley-Davidson
3 reviews $1,499.00

Bates BattBoy Battery Box for Modern Gel or Li-Ion Batteries fits OEM-style Harley-Davidson Horseshoe Oil Tanks
26 reviews $149.09

Lowbrow Customs Reproduction Harley Model 125 / Model 165 / Hummer Gas Tank - With Key Switch
8 reviews $303.11

Kustom Tech DeLuxe 1 inch Clutch Lever Polished Aluminum
8 reviews $246.43

Cycle Standard 14 Piece Aluminum Wheel Axle Spacer Kit - 1.125 inch O.D. x 3/4 inch I.D.
45 reviews $52.80

S&S Cycle Super E Carburetor Kit 1979-84 Harley-Davidson Shovelhead
2 reviews $756.20 $799.95

Lowbrow Customs Shotgun Exhaust Pipes 2004-2021 Harley-Davidson Sportster XL - Raw Steel
3 reviews $299.93

Lowbrow Customs Domed Screw-In Gas Cap for Harley-Davidson 1996 & later - Brass
22 reviews $89.06

Lowbrow Customs Rear Caliper Bracket for Rigid Harleys - 11.5" Rotor - 3/4" Axle - Raw
10 reviews $108.34

Kustom Tech Single Throttle Cable Kit in Brass for S&S Super E / G
24 reviews $144.19

Kustom Tech Deluxe Throttle Housing Polished Aluminum for 1 inch bars
7 reviews $144.03

S&S Cycle Super E Carburetor Kit 1993-99 Harley-Davidson Big Twin
2 reviews $756.20 $799.95

Lowbrow Customs Belt To Chain Conversion Kit 1995-1999 Harley-Davidson Softail - Chrome Sprocket
2 reviews $159.99

Gasbox Chopper DIY Sissy Bar Kit
42 reviews $89.95

S&S Cycle Carb Mainfold Insulator Block for Super E Carburetors S&S Cycle #16-0491
12 reviews $40.95

Coker Tire Firestone ANS Motorcycle Tire 4.00-18
$286.38

Sully's Customs Cobra 2-Up Seat - Black H-Pleat - Rigid Frame
5 reviews $285.99

Lowbrow Customs Belt to Chain Conversion Kit Harley 1200 Sportster 2004 & up - Black Sprocket
50 reviews $209.99

Til Death Cycles 49mm Harley-Davidson Front End Extended Damper Tube Kit
5 reviews $119.12

Lowbrow Customs Premium Stainless Steel Intake Clamp & Seal Kit 1955-1977 Harley-Davidson FL/FX/XL
13 reviews $33.63

Cycle Standard 41MM Chrome Fork Tubes 1949-1976 Harley-Davidson FL - 26 inch - 6 Over
$207.81

Cycle Standard Chrome Fork Neck Cup Kit with Fork Stops for 1949-1987 Harley-Davidson Big Twins
$52.59

Cycle Electric Alternator Kit CE-83T 2007 Harley-Davidson Softail
1 review $708.47 $758.39

Cycle Standard Mustang Gas Tank - Single Filler - 3.3 Gallon
6 reviews $201.66

Kustom Tech DeLuxe 1 inch Master Cylinder Polished Aluminum
9 reviews $470.03

Cycle Standard Frisco Mount 2007-2022 EFI Sportster Gas Tank - Standard Width - 2.5 gallon
15 reviews $234.29

Airspeed Cycles Narrow Bottom Ape Hanger Handlebars - 11 inch Rise - 1 inch - Stainless Steel
$175.00

ODI Vans/Cult V-Twin Motorcycle Grips by ODI - Black - 1 inch
42 reviews $19.95

Kustom Tech Vintage Line Forward Controls - Aluminum & Brass - 1986-99 Harley-Davidson FL/FXST
1 review $1,396.03

Lowbrow Customs 21" Front Ribbed Spool Wheel - 3/4" Bearings - Black
9 reviews $351.33

Haifley Seats King And Queen Seat - Black Pleated - 2004-2021 (Excl. 2007-09) Harley-Davidson Sportsters
$465.00

Belt Drives LTD. 8mm/1.5 inch Primary Belt Drive - Electric Start - 1979-E1984 Harley-Davidson Big Twins
1 review $845.50 $890.00

Kustom Tech 11 inch Spring Struts - Chrome
$690.52

Lowbrow Customs Springer Top Clamp for Standard 3.5" Handlebar Risers
3 reviews $202.45

Mid-USA Four Piston Brake Caliper - Chrome
7 reviews $275.00

Cycle Standard Isolator Motor Mount - Front - 1991-2017 Harley-Davidson Dyna
7 reviews $117.41

Trader Cody's Choppers Midway Mid Controls 1970-1984 Harley-Davidson Shovelhead 1984-1999 Evo - Chrome
$450.00

Mid-USA Dual Piston Brake Caliper - Polished
$192.50

Kustom Tech Classic 1 inch Master Cylinder Polished Aluminum - 12 mm Bore
$447.34

Cycle Standard Braided Stainless Cut-To-Length Compression Brake Line Kit - Black
2 reviews $62.81

James Gaskets Primary Cover Gasket & Seal Kit - 1991-2003 Harley-Davidson Sportster
1 review $30.70

Prism Supply Co. 1/4 inch NPT 90 Degree Petcock - Brass
10 reviews $109.99

Gasbox Upswept Exhaust Pipe Set for 1970-1984 Harley-Davidson Shovelhead Rigid Applications
1 review $329.95

Belt Drives LTD. 11mm/1.5 inch Primary Belt Drive with Idler Gear - Electric Start - 1965-E1984 Harley-Davidson Big Twin
2 reviews $860.11 $905.38

Rich Phillips Seat Co. Leather Solo Seat - Black
51 reviews $219.00

Cycle Standard Ape Hanger Handlebars - 1 inch - 12 inch Rise - Chrome
33 reviews From $123.59

Cycle Standard Bayonet / Cam Harley Style Vented 2" Gas Cap - Chrome
53 reviews $22.46

Prism Supply Co. Sling Shot Clutch Control - Harley-Davidson 5 & 6 Speed - Stainless Steel
4 reviews $324.99

Belt Drives LTD. 8mm/2 inch Primary Open Belt Drive - Kick Start - Spline Shaft - 1955-1984 Harley-Davidson Big Twin
$808.37 $850.92

Lowbrow Customs Belt To Chain Conversion Kit 1984-1994 Harley-Davidson Softail - Black Sprocket
$188.99

Sully's Customs Skinny Style Seat - Black Vertical Pleat - 1982-2003 Harley-Davidson Sportsters
3 reviews $214.99

Performance Machine Performance Machine Classic 4 Piston Brake Caliper - Black
$427.84

Performance Machine Performance Machine Classic 4 Piston Brake Caliper - Chrome
2 reviews $426.95

Lowbrow Customs Belt To Chain Conversion Kit 1984-1994 Harley-Davidson Softail - Chrome Sprocket
$188.99

Mid-USA Hardbody Antique Style Springer Front End - 4 inch Over Length - Chrome
1 review $1,274.50

Drag Specialties Friction Clutch Plate Kit (5-Pack) for 1968-1984 Harley Shovelhead
13 reviews $84.75

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

Lowbrow Customs Gas Tank Adapter Brackets 1982-2003 Harley Sportsters XL
54 reviews $54.00

Shinko Motorcycle Tires SR777 Rear Motorcycle Tire - 130/90B16
2 reviews $156.95

Shinko Motorcycle Tires Super Classic 270 Whitewall Front/Rear Motorcycle Tire - 5.00-16 72H
5 reviews $156.95

Cycle Standard 41MM Chrome Fork Tubes 1984-1999 Harley-Davidson FXWG/D FXST - 30-1/4 inch - 6 Over
$214.38

Mid-USA Rear Caliper Bracket for Rigid Models with 11-1/2 inch Rotors - 3/4" Axle - Chrome
3 reviews $103.95

Lowbrow Customs Manta Ray Smooth Steel Fender 7 inch Width
21 reviews $209.53

Cycle Standard Mustang Gas Tank - Dual Filler - 3.3 Gallon
2 reviews $182.75

Kustom Tech DeLuxe 1 inch Clutch Lever Polished Aluminum & Brass
15 reviews $248.66

Cycle Standard Bates Style Rectangular Motorcycle Headlight - Yellow Lens - Chrome
1 review $65.00

Cycle Standard Narrow Ribbed Mustang Gas Tank 2.25 gallon
31 reviews $204.55

Sully's Customs Solo Seat - Black Horizontal Pleat - Rigid Frame
3 reviews $175.00

Cycle Standard Stock Style Harley-Davidson Sportster Gas Tank 2004-2006 - 2.2 gallon
6 reviews $246.02

Biltwell Slimline Risers - Polished Stainless Steel - 1 inch
37 reviews $149.95

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.

Read less

Custom Motorcycle Parts FAQ

STAY CONNECTED
WITH LOWBROW

NO SPAM, EVER. JUST GREAT STUFF. YOUR INFO IS NEVER SHARED.