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

Colony #2094-4 Handlebar Riser Allen Bolt Kit 1/2-13 x 2-1/2" Harley-Davidson FLST Models - Chrome Plated
5 reviews $14.89

Goodridge Short 90 Degree Tube Adapter - Ebony
3 reviews $18.95

Cycle Standard Reverse Cone Shorty Megaphone Exhaust Mufflers - Chrome
42 reviews $208.31

Colony #3647-10 Sprocket Bolt Kit 1973-Up Harley-Davidson Big Twin & Sportster Chain Drive Models - Chrome Plated
$26.00

Lowbrow Customs Ovate Axed Gas Tank - Super Narrow - 1.6 gallon
10 reviews $207.84

Cycle Standard 5 Post Ignition Key Switch Replaces Harley-Davidson OEM #71500-36T - Black Bezel
10 reviews $51.91

British Standard Rocker Box Oil Feed Pipe for Triumph 650 / 750 c.c. 1963 - 1982 #71-2428
6 reviews $103.82

Cycle Standard 39mm Damper Tube Kit - 9.5" - 1994-1996 Harley-Davidson Sportster XL 1995-2017 FXD OEM# 45925-94
$69.00

James Gaskets Primary Cover & Inspection Cover Gasket Kit With Seals 1984-1986 Harley-Davidson FL/FLH/FX/FXE/FXWG 1984-1988 Softail
$68.87

Cycle Standard Throttle Cable OEM #56400-96 Harley Sportster XL 1996-Up +4 inch Extended
5 reviews $41.31

S&S Cycle Quickee Adjustable Pushrod Set - 1984-1999 Harley-Davidson Big Twin
2 reviews $206.26 $224.95

Cycle Standard Narrow Alien Motorcycle Gas Tank - 2.1 gallon
10 reviews $205.99

Lowbrow Customs Bolt On 13/16 inch Ignition Switch Mounting Tab / Bracket - Tumbled Stainless
9 reviews $15.82

Lowbrow Customs Bolt On 3/4 inch Ignition Switch Mounting Tab / Bracket - Tumbled Stainless
38 reviews $15.82

Lowbrow Customs Brass Nuts & Nickel-Plated Ring Terminals for Spark Plug Wires
28 reviews $22.85

Cycle Standard Universal Mini Horn 2.5 inch diameter - Chrome
26 reviews $29.35

Kustom Tech 1 inch Clamp with Micro Switch - Polished
8 reviews $102.62

S&S Cycle Fuel Inlet 360 degree Swivel Fitting by S&S Cycle #106-2011
16 reviews $40.95

Colony #2939-26 Complete Springer Rocker Rebuild Kit 1931-1948 Harley-Davidson Big Twin - Parkerized
2 reviews $204.20

Golan Products Inc. 22MM Click-Slick Petcock - Round Body - Raw Brass - Downward
2 reviews $204.14

James Gaskets Motor Gasket Kit W/Alum-Foamet Base 1948-1965 Harley-Davidson Panhead
$101.74

Cycle Standard Engine Stabilizer Link - Chrome - 1995-2017 Harley-Davidson Dyna
$101.74

Cycle Standard Tombstone LED Taillight w/ Red Turn Signals - Red Lens - Chrome
4 reviews $101.71

Colony #8224-8 Rocker Shaft End Plug & Cap Kit 1971-Up Harley-Davidson Shovelhead 1971-1985 XL - Chrome Plated
9 reviews $40.61

Colony #1013-P Complete Show Bike Kit Smooth Allen Hardware 1994-2003 Harley-Davidson Sportster - Chrome Plated
4 reviews $201.81

Cycle Standard Drilled Stainless Steel Brake Rotor - 10 inches - Replaces Harley-Davidson OEM #44137-77A
2 reviews $100.89

Cycle Standard Forward Control Shift Lever - Chrome - Harley-Davidson OEM #34670-06
$40.35

Drag Specialties Wheel Bearings and Races - Replaces Harley-Davidson OEM #9052
3 reviews $28.80

Lowbrow Customs Exhaust Spigot Adapters for 1972-up OIF Triumph Motorcycles
12 reviews $50.36

Lowbrow Customs Axle Spacer Kit for Lowbrow Ribbed Spool Wheel - Mid-USA Antique Style Springer
3 reviews $25.16

Gates Corporation 1/4 inch Black Fuel / Oil Line - By The Foot
10 reviews From $10.59

Lowbrow Customs Clutch / Brake Cable Clamp - Black - for 1-1/8 inch Frame Tubing
6 reviews $20.05

Colony #2349-6 Handlebar Heavy Duty Damper Kit 1973-Up Harley-Davidson Big Twin & Sportster
17 reviews $20.04

Cycle Standard 1/4 inch NPT Petcock Chrome - 90 Degree
26 reviews $40.06

Cycle Standard Primary Chain Adjuster Kit - 1991-2003 Harley-Davidson Sportster XL
2 reviews $40.04

Cycle Standard 1/4 inch NPT Petcock Chrome - Straight
25 reviews $40.03

Cycle Standard Neck Post Bearing & Race Set - Imported
$14.29

Cycle Standard 28 degree 3/8 inch/10mm Compression Banjo Fitting - Stainless
$14.29

Old-Stf Cycle Pushrod Cover Keeper Set - Drilled Brass - Big Twin Evo Shovelheads & Knuckles
19 reviews $40.00

Mid-USA 16 x 3 Black Antique Style Front Spool Wheel
$199.99

Mid-USA 16 x 3 Chrome Antique Style Front Spool Wheel
$199.99

Mid-USA 21 x 2.15 Black Antique Style Front Spool Wheel
1 review $199.99

Prism Supply Co. Prism Supply Bell Tail Light - Brushed Aluminum
$99.99

Led Sled Customs Derby Oil Tank for Harley-Davidson Choppers
5 reviews $199.95

Biltwell Thunder Risers - Polished Stainless
7 reviews $199.95

Gasbox Complete Hardware Kit for Gasbox Rigid EVO Sportster Frames with Frisco Tanks
1 review $99.95

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

Gasbox Primary Mount License Plate Bracket - 1967 - 2003 Sportsters
19 reviews $49.95

Gasbox Shock Mount License Plate Bracket
15 reviews $49.95

Goodridge 1/8 inch NPT Universal Rear Brake Tee - No Mount - Ebony
2 reviews $19.95

British Standard Smiths Tachometer Replica - Grey Face 4:1 Ratio - For Triumph Motorcycles
5 reviews $99.56

Cycle Standard Small Flush Mount Pop-Up Gas Cap & Weld-In Bung - Vented - Aluminum
$99.27

Colony #3670-10 Rear Sprocket Bolt Kit - Domed Hex Bolt Harley-Davidson 2006-Up Dyna 2007-Up Softail - Chrome Plated
2 reviews $33.00

Colony #2886-24 Valve Spring Cover Kit 1937-1938 Harley-Davidson Big Twin Side Valve - CAD Plated
1 review $198.00

Standard Motorcycle Products Ignition Sensor Assembly - 1980-1994 Harley-Davidson XL 1984-1985 FXST 1980-1993 FLT
3 reviews $65.95

Goodridge Universal Braided Stainless Brake Line - 26" - Ebony
3 reviews $32.95

Gasbox S&S Carburetor Support Bracket - Harley-Davidson Evo Big Twin and Strokers - Tumbled Stainless
10 reviews $21.95

Gasbox Heavy Duty Coil Mount - Big Twin 1965 - 1982
18 reviews $21.95

Cycle Standard Rim Strip for 18 inch / 19 inch Motorcycle Wheels
23 reviews $4.03

Drag Specialties 15A Circuit Breaker 1970-1999 Harley-Davidson Big Twin/XL 1999 Twin Cam
1 review $10.95

Cycle Standard Polished Cast Tail Light Bracket for Lucas Style Tail Light
6 reviews $65.67

Dunlop Tires K70 4.00-18 Front/Rear Motorcycle Tire
6 reviews $196.95

Cycle Standard Mini 2:1 ratio Mechanical Speedometer with Trip Meter - 2.4 inch
12 reviews $98.46

Colony #1014-P Complete Show Bike Kit Smooth Allen Hardware 1991-1993 Harley-Davidson Sportster - Chrome Plated
$196.13

Colony #3537-17 Primary Cover Allen Screw Kit 1971-Up Harley-Davidson Shovelhead & Evolution 4 Speed
4 reviews $16.34

Gasbox Bolt-On Lower Fender Bracket for Gasbox Big Twin Frames
$28.00

Cycle Standard Tombstone LED Taillight - Smoked Lens - Black
$65.28

Colony #8806-17 Motor Mounting Kit Upper & Lower 1970-1984 Harley-Davidson Big Twin - Chrome Plated
4 reviews $39.11

James Gaskets Exhaust Gasket/Mounting Kit for Harley-Davidson 1984-2013 Big Twins and 1986-2013 XL
16 reviews $24.43

EMGO Aris Style Triangular Headlight - Chrome
14 reviews $97.59

FNA Custom Cycle Dual Headlight Mount - Long - Stainless Steel
$195.00

FNA Custom Cycle Dual Headlight Mount - Short - Stainless Steel
2 reviews $195.00

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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