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

Forever The Chaos Life FTCL - SHoRTi Foot Pegs - 7075 Aluminum - Raw Machined Finish
$99.95

Prism Supply Co. Prism Supply Co. 1.25 inch Speedster Tail Light - Brushed Aluminum
11 reviews $99.95

Biltwell Dual Cable Cast Whiskey Throttle - Black - 1 inch
29 reviews $99.95

Goodridge P6150-03C 150 Degree Tube Adapter - Stainless Steel
2 reviews $49.95

Goodridge 1/8 inch NPT Universal Rear Brake Tee - With Mount - Ebony
$49.95

Gasbox Oil Filter Front Motor Mount Plates for 1957 - 1981 Harley-Davidson Ironhead Sportster
4 reviews $49.95

James Gaskets Fork Seal Rebuild Kit 1975-1984 35mm Harley-Davidson FX and XL Models
7 reviews $22.19

Lowbrow Customs Springer Riser Studs 1/2-13 x 1/2 inch-20 thread for Harley, Mid-USA, DNA, Paugcho Springers
84 reviews $15.97

Lowbrow Customs Black Steel Solo Seat Hinge / Pivot Bracket - 1963-70 Triumph
18 reviews $99.31

S&S Cycle Mini Teardrop Stealth Air Cleaner - Chrome - 2017-Up Harley-Davidson M8 Models
1 review $395.95

S&S Cycle Tear Drop Air Cleaner - Black - 1991-2006 Harley-Davidson Sportster XL
2 reviews $395.95

Lowbrow Customs Radius Breather Bolts for Harley-Davidson Twin Cam - Chrome Plated
19 reviews $49.49

Cycle Electric Generator DGV-2569M 65A 12v for 1936-1957 Harley-Davidsons with 5/16-24 mounting bolts
$395.86 $423.75

Gasbox S&S Carburetor Support Bracket - Harley-Davidson Shovelhead - Tumbled Stainless
55 reviews $21.95

Cycle Standard Clutch Cable OEM #38619-86A 1986-2003 Harley-Davidson 883 Sportster XL +8 inch Extended
$49.13

Cycle Standard 49mm Fork Leg Assembly Rebuild Kit 2016-2021 Harley-Davidson XL1200X 2018-2023 Softails 2014-2023 FLHT/FLHR/FLHX/FLTRX/FLTRU/FLTRK
2 reviews $98.23

Amal Carburetor Gasket, Float and Complete Rebuild Kit for 626 928 930 932 Concentric Carbs
15 reviews $98.04

Mooneyes MOON Pressure Gauge 0-100 psi
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Gasbox Chrome Shorty Grab Bar - Round Fender
8 reviews $129.95

Cycle Standard 1/4 inch Braided Stainless Fuel Line Kit
8 reviews $48.71

Cycle Electric Alternator Kit CE-22ANBR for 1970-1998 Harley-Davidson Big Twins With No Battery
$388.34 $415.70

British Standard 1/4 inch BSP Petcock Fuel Valve - Reserve - For Triumph BSA Norton
17 reviews $27.72

Cycle Standard Clutch Hub Bearing Kit - 1941-84 Harley-Davidson Big Twins
4 reviews $48.40

LePera Bare Bones Solo Seat - Pleated - fits 1984-1999 Harley-Davidson Softail
$387.00

Cycle Standard Chrome Kickstand - 1 inch Under - 1989-2003 Harley-Davidson XL Models - OEM #50006-89
15 reviews $55.27

Lowbrow Customs Frisco Mount Banana Gas Tank - Bayonet Filler - Shallow Tunnel
4 reviews $192.94

Unity Manufacturing TUFF Stainless Steel Brake Rotor - 10 inch - Rear
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Motone Monza Flip-Up Gas Cap - Polished Aluminum - Vented 2.5" Diameter
5 reviews $64.24

Lowbrow Customs Drag Bar Handlebars - 1 inch - Black
19 reviews From $54.99

Colony #8515 Complete Show Bike Kit Cap Style Hardware 1976-1977 Harley-Davidson Shovelhead - Chrome Plated
$383.08

Colony #7908 Complete Show Bike Kit Acorn Hardware 1958-1965 Harley-Davidson Panhead - Chrome Plated
$383.08

Colony #2188-4 Exhaust Port Studs Kit 1984-2025 Harley-Davidson Big Twin and 1986-2022 XL - Zinc Plated
7 reviews $16.64

Golan Products Inc. 22MM Click-Slick Petcock - Round Body - Raw Brass - Forward
2 reviews $190.95

Hawg Supply Flatty 4" Air Cleaner CV Carburetor - Brushed Aluminum
$189.99

Hawg Supply Watson 4" Air Cleaner CV Carburetor - Brushed Aluminum
$189.99

Hawg Supply Swirl 4" Air Cleaner CV Carburetor - Brushed Aluminum
1 review $189.99

Unity Manufacturing Solid Stainless Steel Brake Rotor - 11.5 inch - Rear
$189.99

Gasbox Chrome Kick Back Sissy Bar - Round Fender - Model A Tail Light
1 review $189.95

Gasbox Chrome Kick Back Sissy Bar - Flat Fender - Model A Tail Light
$189.95

Gasbox Chrome Pointed Sissy Bar - Flat Fender - Box Tail Light
$189.95

Cycle Standard Solo Custom Mini Rear Brake Master Cylinder Assembly - Black
$189.58

Cycle Standard 41MM Chrome Fork Tubes 1949-1976 Harley-Davidson FL - 22 inch - 2 Over
1 review $189.55

Colony #2322-11 Rocker Arm Cover Stud Kit 1966-1984 Harley-Davidson Shovelhead
4 reviews $47.38

Cycle Standard Nose Cone Cam Gear Cover - Chrome - 1973-92 Harley-Davidson Big Twin
2 reviews $189.33

Cycle Standard Asphalt Wire Loom - 3/8 Inch Diameter, 10-Foot Length for Wiring Protection
21 reviews $29.12

Lowbrow Customs Bolt-On Battery Box & Fender Mount for 1982-2003 Sportster Weld-On Hardtail
11 reviews $37.83

Cycle Standard Bayonet / Cam Harley Style Vented 2" Gas Cap - Black
33 reviews $19.84

S&S Cycle Mini Teardrop Stealth Air Cleaner - Chrome - 2007-Up Harley-Davidson Sportster XL
$367.95

Cycle Standard Replacement Dished Sprocket - Chrome - 51 Tooth - 1973-84 Harley-Davidson Big Twin 1979-81 XL OEM #41470-73
1 review $75.02

Lowbrow Customs 60 PSI Harley Oil Pressure Gauge - Black Face
39 reviews $46.85

Cycle Standard 3 position Ignition Key Switch Replaces Harley-Davidson OEM #71425-77 - Black Body / Black Bezel
16 reviews $41.49

Cycle Standard Motorcycle Tire Inner Tube 16" / 130/90 140/90 MT90 MU85 Side Metal Valve
$17.59

Cycle Standard Universal Replacement Baffle for 1-3/4" Exhaust Pipes
1 review $13.19

Lowbrow Customs Weld-On Upper Fender Mount Tab for Flat and Trailer Motorcycle Fenders
40 reviews $17.58

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

Cycle Standard Mega Nut Sprocket and Pulley Lock Nut for 1993+ Harley Sportster, Big Twin, and Twin Cam
19 reviews $73.66

Lowbrow Customs S&S Super E Carb Extended Float Bowl Screws - Chrome — Lowbrow Customs S&S Super E and G Carb Extended Float Bowl Screws - Chrome
48 reviews $45.76

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

Colony #1008 Complete Show Bike Kit Allen Hardware Harley-Davidson 1985-1986 Evo 5 Speed - Chrome Plated
$181.91

Cycle Electric Regulator CE-540L for use on 12v Harley-Davidson Generators
22 reviews $181.55 $194.34

British Standard Triumph TT Style Exhaust Pipes
11 reviews $362.93

Lowbrow Customs Classic Grips - Black - 1 inch
39 reviews $18.10

Cycle Electric CE-500 Replacement Regulator for DGV-5000 Generator
1 review $180.23 $192.93

Prism Supply Co. Bristol Breather - CV Carburetor - Polished
$60.00

Martian Machine Rabbit Ears Handlebars - Raw Steel
3 reviews $120.00

Monster Craftsman Weld on Tensioner Single Sided Mount 530 Sprocket
2 reviews $119.99

Prism Supply Co. Prism Supply Co. Steel Flat Tail Light - Weld-On
$89.99

Goodridge Universal Braided Stainless Brake Line - 38" - Ebony
7 reviews $44.95

EMGO Complete Engine Gasket Set with Head Gasket Triumph 750cc 1973-1983 T140 Bonneville TR7
2 reviews $119.86

Bates BattBoy 65 Battery Box 1965-84 Harley-Davidson FL FLH and 1967-78 XL
9 reviews $119.81

Drag Specialties Fat Bob Flatside Style Gas Tanks - 1984-1999 Harley-Davidson FXST/FLST 1985-1986 FX/FXWG - 3.5 Gallon
$358.23

Dunlop Tires K70 3.25-19 Front/Rear Motorcycle Tire
5 reviews $178.95

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.

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