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

Cannonball Stealthstarter Electric Starter Kit Rigid Frame 3 & 4 Speed Harley-Davidson Big Twins
3 reviews $3,894.96

Cannonball Stealthstarter Electric Starter Kit Swingarm Frame 4 Speed 1958-1985 Harley-Davidson Big Twins
1 review $4,260.63

Shinko Motorcycle Tires Super Classic 270 Front/Rear Motorcycle Tire - 5.00-16 72H
16 reviews $144.95

Lowbrow Customs Weld-On Hardtail Frame for 1982-2003 Harley-Davidson Sportster
97 reviews $447.19

Shinko Motorcycle Tires Super Classic 270 Front Motorcycle Tire - 3.00-21 57S
15 reviews $116.99

Lowbrow Customs Weld-On Ironhead Hardtail Rear Frame Section for 1952-1981 Harley-Davidson Sportster
22 reviews $447.19

S&S Cycle S&S Super E Carburetor Assembly - fits Harley Big Twin & Sportster
16 reviews $469.95 $499.95

Top view Frisco mount Sportster Gas Tank by Lowbrow Customs — Lowbrow Customs Frisco Mount Sportster Gas Tank - Standard Width - 2.5 gallon
110 reviews $218.88

Lowbrow Customs Manta Ray Smooth Steel Fender 6 inch Width
78 reviews $207.12

Gasbox Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 5 Speed - 3" Up - Frisco Tank Mounts - Horseshoe Oil Tank
2 reviews $1,799.00

Lowbrow Customs Weld-On Hardtail Frame for 2004-2022 Harley-Davidson Sportster
10 reviews $468.00

S&S Cycle S&S Super E Carburetor Rebuild Kit #11-2923 for Harley Davidson
28 reviews $105.95

Mid-USA 6 Speed Transmission - Polished Finish - 1990-1999 Harley-Davidson Softail
1 review $1,289.00 $1,451.70

Mid-USA 6 Speed Transmission - Black Finish - 1990-1999 Harley-Davidson Softail
$1,289.00 $1,443.75

Gasbox Bolt-On Horseshoe Oil Tank for 1965-Up Harley Four-Speed Swingarm Frames
28 reviews $299.99

Antigravity Batteries Antigravity Lithium Small Case Battery - 12 Cell - AG-1201
38 reviews $219.99

Mid-USA Hardbody Antique Style Springer Front End - 2 inch Under Length - Chrome
3 reviews $983.50

Lowbrow Customs 21" Front Ribbed Spool Wheel - 3/4" Bearings - Chrome
24 reviews $346.78

Cycle Standard 39MM Chrome Fork Tubes - 31 inch - 6 Over
21 reviews $257.77

Prism Supply Co. 4-1/2 inch Round LED Headlight
5 reviews $189.99

Lowbrow Customs T-Bars Handlebars - 10 inch Rise - 1-Inch Diameter - Chrome
29 reviews From $143.12

Lowbrow Customs Manta Ray Smooth Steel Fender 4-3/4 inch Width
70 reviews $206.93

Cycle Standard Wassell Peanut Mid-Tunnel Gas Tank 2.1 gallon
45 reviews $220.00

Dynatek Performance Electronics Dyna S Ignition Complete Kit - Dual Fire for Harley Davidson
19 reviews $264.29

V-Twin Manufacturing Complete 21 inch Spool Hub Chopper Wheel - 3/4 inch Bearings
11 reviews $265.71 $280.49

Gasbox Bolt-On Oil Tank for Rigid Harley-Davidson Big Twin Frames with Electric Start
1 review $299.99

Belt Drives LTD. 2" SS Belt Drive - Without Cover - 1990-2006 Harley-Davidson FXST/FLST
$2,790.51 $2,937.38

Shinko Motorcycle Tires Shinko Motorcycle Tires Classic 240 Front/Rear Motorcycle Tire - MT90-16 74H
9 reviews $153.95

Lowbrow Customs Weld-On Hardtail Frame 1958-1984 Harley-Davidson Panhead & Shovelhead
2 reviews $699.99

Lowbrow Customs Belt to Chain Conversion Kit Harley 1200 Sportster 1995-2003 - Chrome Sprocket
25 reviews $173.40

Lowbrow Customs Frisco Mount Sportster Gas Tank - Narrow - 2.1 gallon
69 reviews $232.63

Lowbrow Customs Rogue Fender - 1958-84 Harley-Davidson Panhead Shovelhead
129 reviews $318.57

Mid-USA 16 x 3.00 Black Complete Rear Wheel fits all Harley-Davidson 1979-1999
11 reviews $203.25

Lowbrow Customs Complete Chopper Wiring Harness 2007-2013 EFI Harley-Davidson Sportster
1 review $579.99

Prism Supply Co. Sportster Mid-Control Kit for 1991-2003 Harley-Davidson - Stainless Steel
6 reviews $299.99

Belt Drives LTD. 8mm/1.5 inch Primary Belt Drive - Kick Start - 1965-1978 Harley-Davidson Big Twins
$726.39 $764.62

Coker Tire Firestone ANS Motorcycle Tire 5.00-16
5 reviews $260.55

Cycle Standard Ribbed Steel Fender 5 inch Width
9 reviews $169.33

Cannonball Heavy Duty Kickstarter Kit fits 1985-1998 Harley-Davidson 5-Speed Big Twin
1 review $2,196.55

Diamond 530 Drive Chain - 120 links USA made
21 reviews $174.56 $193.95

Gremlin Wiring The Sportster Treatment Custom Wiring Harness Kit 1999-2003 Harley-Davidson Sportster Models
38 reviews $249.95

Bates Baja 90 Tire 16" - 130/90B16 73R
35 reviews $248.71

Cycle Electric CE-84T-99 Stator Rotor and Regulator Kit for 1999 - 2003 Harley-Davidson FLH and FLT Models
21 reviews $545.16 $583.57

Lowbrow Customs Horseshoe Oil Tank for Lowbrow Customs Weld-On Sportster Hardtails and Gasbox Full Frames
50 reviews $311.99

Mid-USA Harley Sportster 21" Front Wheel - Chrome Finish
17 reviews $332.40

Lowbrow Customs Rabbit Ears Handlebars - 1 inch - Chrome
37 reviews From $142.66

Tri-Spark Tri-Spark Classic Twin Electronic Ignition System for Triumph BSA Norton Twins And SIngles
17 reviews $327.06

EMGO Cocktail Shaker Mufflers for 1-1/2 to 1-3/4 inch Exhaust Pipes
82 reviews $220.93

Lowbrow Customs High Mids Foot Controls - Bolt-On Kit for 2004-Up Harley-Davidson Sportsters
2 reviews $499.99

Old-Stf Cycle Centerline Adjustable Aluminum Transmission Plate - Harley-Davidson Big Twin 4 Speeds
5 reviews $249.00

Performance Machine Performance Machine Classic 4 Piston Brake Caliper - Polished
$385.43

Dynatek Performance Electronics 2000I PC Programmable Electronic Ignition Kit for Harley-Davidsons
9 reviews $320.27

FNA Custom Cycle Tite Seal Intake Manifold Kit for 1948-1984 Harley Big Twin & Sportster
67 reviews $55.95

Cycle Standard 39MM Chrome Fork Tubes - 35 inch - 10 Over
$313.69

Bates Baja 100 Tire 21" - 3.00-21 57T
8 reviews $185.45

Cycle Standard 39MM Chrome Fork Tubes - 27 inch - 2 Over
1 review $209.58

American Prime Mfg. Brake/Mechanical Clutch Control Kit for 1 inch Handlebars - 9/16 inch Bore - Polished
4 reviews $366.14

Lowbrow Customs Straight Leg Bolt-On Hardtail Rear Frame Section for 1967-1978 Harley-Davidson Ironhead Sportster
17 reviews $405.59

Lowbrow Customs Frisco Mount Sportster Gas Tank - Standard Width - Bayonet Filler - 2.5 gallon
16 reviews $219.94

Cycle Standard Motorcycle Tire Inner Tube - 5.00 / 5.10-16 inch Side Metal Valve
15 reviews $32.18

American Prime Mfg. Complete Comp Master Clutch fits 1936-1984 Harley-Davidson Pre-EVO Big Twin
2 reviews $639.76

Cycle Electric Alternator Kit 32 amp CE-32AR for Harley-Davidson Evo Big Twins
4 reviews $367.45 $393.34

Drag Specialties 530 O-Ring Drive Chain - 130 Links includes Master Link
7 reviews $172.87

American Prime Mfg. Brake/Mechanical Clutch Control Kit for 1 inch Handlebars - 11/16 inch Bore - Polished
1 review $366.14

Lowbrow Customs Original P-Nut Tank Deep Tunnel Gas Tank 1.8 gallon
62 reviews $205.99

Prism Supply Co. Quick Stick Start Lever 2.0 1991-Up Harley-Davidson Sportster 1989-Up Big Twin - Matte Aluminum
6 reviews $119.99

Lowbrow Customs T-Bars Handlebars - 12 Inch Rise - 1 inch Diameter - Chrome
5 reviews $144.14

Cycle Standard Stock Style Harley Sportster Gas Tank 1986 - 2003 - Left Side Petcock - 2.2 gallon
72 reviews $218.85

Lowbrow Customs 39mm Narrow Triple Trees Kit
3 reviews $399.99

Cycle Electric Generator DGV-5000L 12 Volt - Low Voltage - 1965-1984 Harley-Davidson
44 reviews $543.94 $582.26

Lowbrow Customs Radius Breather Bolts for Harley-Davidson Evo - Chrome Plated
101 reviews $49.49

Lowbrow Customs Weld-On Upper Fender Mount Tab for Curved and Ribbed Motorcycle Fenders
108 reviews $30.02

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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