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

Prism Supply Co. Ripple Shift Knob - Polished Brass
1 review $46.99

Cycle Standard Replacement Flat Sprocket - Chrome - 51 Tooth - 1982-1992 Harley-Davidson Sportster OEM #41464-86
$75.02

Mooneyes 4 quart Traditional Chopper Oil Tank for Harley-Davidson Choppers
6 reviews $375.00

Sully's Customs Vertical Pleated Solo Seat - Black
4 reviews $124.99

James Gaskets Exhaust Port Gasket Kit - Thick Graphite Wire Gaskets & Hex Nuts - 1984-Up Harley-Davidson Evo/Twin Cam 1986-2022 XL
$24.95

Lowbrow Customs Dished Screw-In Gas Cap for Harley-Davidson 1996 & later - Aluminum
4 reviews $53.41

Pingel 22MM Power-Flo Petcock - Hex Body - Black - Inward
$184.95

Cycle Standard Ape Hanger Handlebars - 1 inch - 12 inch Rise - Black
16 reviews From $122.82

EBC Brakes Sintered Rear Brake Pads 2000-03 H-D Sportster XL 00-07 Big Twin models 02-05 V-Rod
$46.02 $47.88

Drag Specialties Predator III 2-Up Seat - Smooth - 1982-2003 Harley-Davidson Sportster XL
$426.95

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

Lowbrow Customs CV Carb Extended Float Bowl Screws - Brass
19 reviews $45.76

Cycle Standard Super Nut for Harley-Davidson Four Speed Transmission - OEM #35211-36
26 reviews $33.18

Drag Specialties High Performance Starter Solenoid 1965-1984 Harley-Davidson Big Twin 4 Speed 1967-1980 XL 1984-1988FXST/FLST 1985-1986 FXWG/FXSB
3 reviews $91.13

Burly Brand Slammer Plus Shocks - 1988 - 2003 Harley-Davidson Sportster XL - Chrome
$364.46 $404.95

Goodridge Universal Braided Stainless Brake Line - 50" - Ebony
4 reviews $51.95

GMA Engineering 1 inch Brake Master Cylinder Assembly - Black - 5/8 inch Bore
$363.38

Cycle Standard 22mm Petcock Harley-Davidson Style - Black - Left Hand Outlet
24 reviews $40.36

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

EMGO Chromed Steel Brake and Clutch Blade Levers Control Set for 1 inch Bars
11 reviews $51.83

Cannonball Extended Crossover Shaft For Use With Stealthstarter Electric Starter Kit Rigid Frame 4 Speed Harley-Davidson Big Twins
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Lowbrow Customs Classic Grips - Black - 1 inch
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Colony #9424-8 Cylinder Base Stud Set 1985-1999 Harley-Davidson Big Twin Evo
$90.20

Prism Supply Co. Prism Supply Co. Bullet Tail Light - Bolt-On
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Hawg Supply Quick-Pull Clutch Cable Bracket V2.0 For Harley-Davidson Ratchet Top 4 Speed Transmissions
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V-Factor Motorcycle Parts Lever Action Starter Solenoid 1965-1986 Harley-Davidson Big Twin 4 Speed 1984-1988 Softail - Black
2 reviews $119.95

Prism Supply Co. 1/4 inch NPT Petcock - Stainless Steel
13 reviews $119.95

Drag Specialties Chrome Steel Front Brake Tee with Fittings for Dual-Disc Applications
$51.40

Gasbox Chopper DIY Sissy Bar Kit
43 reviews $89.95

Gasbox Big Twin 4 Speed Oil Filter Mounting Bracket
$59.95

Goodridge Universal Braided Stainless Brake Line - 19" - Ebony
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Biltwell Kung Fu TPV Grips- Black - 1 inch
17 reviews $19.95

Monster Craftsman Powell Peralta Weld-on Chain Tensioner
3 reviews $119.00

S&S Cycle Mini Teardrop Stealth Air Cleaner - Chrome - 2017-Up Harley-Davidson M8 Models
1 review $356.36 $395.95

Drag Specialties Tombstone Taillight - Top Tag - Red Lens
$118.72

Autolite Spark Plug- 1975-1981 Shovelhead & Evo Big Twins - Manufacturer Part #4265
14 reviews $7.70

British Standard Fork Bushing & Seal Kit for Triumph Motorcycles
8 reviews $88.34

Progressive Suspension 413 Series Shocks - Heavy Duty - 15" inch - 1986-2020 Harley-Davidson Sportster XL
2 reviews $351.95

Cycle Standard 41MM Chrome Fork Tubes 1984-1999 Harley-Davidson FXWG/D FXST - 24-1/4 inch
$175.80

Kustom Tech Custom Rear Master Cylinder - Polished
$351.07

Lowbrow Customs Black Steel Solo Seat Hinge / Pivot Bracket - Bolt-On
8 reviews $87.62

Haifley Seats King And Queen Seat Pan - 2004-2021 (Excl. 2007-09) Harley-Davidson Sportsters
$175.00

Airspeed Cycles Narrow Bottom Ape Hanger Handlebars - 7 inch Rise - 1 inch - Stainless Steel
$175.00

Cycle Standard Cast PK Style Sparto LED Tail Light - Aluminum
1 review $70.00

FNA Custom Cycle FNA Far-E Headlight - Clear Lens
1 review $350.00

Gasbox Axle Mount License Plate Bracket - 3/4 inch Axles - Vertical or Horizontal
7 reviews $69.95

James Gaskets Complete Motor Gasket Kit - Shovelhead 1966 - 1984
8 reviews $116.17

Colony #9926-17-P Upper and Lower Motor Mount Smooth Allen Kit 1970-1984 Harley-Davidson Shovelhead - Chrome Plated
3 reviews $43.45

Cycle Standard Ignition Coil 4 ohm for Electronic Ignition
5 reviews $69.50

British Standard TR6C Style Exhaust Pipes for Triumph Bonneville 650 Unit or Pre-Unit - Chrome
13 reviews $346.53

Pingel 22MM Power-Flo Petcock - Round Body - Chrome - Forward
1 review $173.00

Cycle Standard Passenger Peg Set With Male Mounting Stud 1984-1999 Harley-Davidson Softails
$69.12

Unity Manufacturing Rear Brake Caliper Bracket for Swingarm Harleys - 10" Rotor - 3/4" Axle - Raw
$115.00

Burly Brand Scrambler Handlebars - 1 inch - Black

1 $171.86 $190.95

Drag Specialties Fat Bob Style Gas Tanks - 1984-1999 Harley-Davidson FXST/FLST 1985-1986 FX/FXWG - 5 Gallon
$343.39

Cycle Standard Forward Control Kit 1991-2003 Harley-Davidson Sportsters - Black - OEM #33891-98
18 reviews $342.27

Burly Brand Stiletto Shocks - 15 inch - Harley-Davidson Sportster XL Models
5 reviews $341.96 $379.95

Drag Specialties Wheel Bearings and Races for Harley-Davidson OEM #9267
$42.56

Cycle Standard Crocker Style LED Tail Light - Aluminum
$85.00

Sully's Customs Traditional Solo Seat - Black
19 reviews $84.99

Drag Specialties Diamond Pattern Gas Tank 2004 - 2006 Sportster XL Models
5 reviews $338.09

Lowbrow Customs Smooth 1" Handlebar Risers - Aluminum
1 review $112.47

Lowbrow Customs Finned 1" Handlebar Risers - Aluminum
15 reviews $112.47

Lowbrow Customs Finned 1" Handlebar Risers - Black
20 reviews $112.47

Cycle Standard Rear Fender Strut Set - 1973-1978 Harley-Davidson Sportster XL - No Turn Signals
2 reviews $112.40

Kustom Tech Carb Mounted Chrome Petcock for S&S Carburetor
3 reviews $112.38

Cycle Standard Rocker Box D-rings - Polished - 1948-65 Harley-Davidson Panhead
$111.74

Cycle Standard Brake/Mechanical Clutch Controls Kit - Black - 1999-2007 Harley-Davidson FLT/FLHX/FLHT/FLTR/FLHR
$333.96

Drag Specialties Clutch Cable Harley-Davidson 4 Speed Big Twin 1968-86 - 56" Long
2 reviews $66.73

Cycle Standard Motorcycle Mirror Clamp - Black - for 1 inch Handlebars
24 reviews $23.83

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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