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

Cycle Standard Bobbed Rear Fender Without Light Mount for 1984-1999 Harley-Davidson Softail
6 reviews $185.88

Cycle Standard Ape Hanger Handlebars - 1 inch - 12 inch Rise - Chrome
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Sully's Customs Cobra 2-Up Seat - Black H-Pleat - Rigid Frame
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Cycle Electric Alternator Kit 32 amp CE-32AR for Harley-Davidson Evo Big Twins
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American Prime Mfg. Brake/Mechanical Clutch Control Kit for 1 inch Handlebars - 11/16 inch Bore - Polished
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Cycle Electric LeBeef Generator DGV-5000-CP 12 Volt - 1965-1984 Harley-Davidsons
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Cycle Standard Smooth Radius Steel Fender 5-1/2 inch Fender
12 reviews $169.59

Prism Supply Co. Super Prism Throttle - 1 inch
3 reviews $229.99

Bates Baja 90 Tire 16" - 130/90B16 73R
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Lowbrow Customs Radius Breather Bolts for Harley-Davidson Evo - Chrome Plated
101 reviews $49.49

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

Lowbrow Customs 21" Front Ribbed Spool Wheel - Black
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Lowbrow Customs Straight Leg Bolt-On Hardtail Rear Frame Section for 1967-1978 Harley-Davidson Ironhead Sportster
17 reviews $405.59

EMGO Cocktail Shaker Mufflers for 1-1/2 to 1-3/4 inch Exhaust Pipes
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Lowbrow Customs Shotgun Exhaust Pipes 1990-2003 Harley-Davidson Sportster XL - Raw Steel
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Lowbrow Customs Straton Springer Front End - 24" Length (6" Over) - Chrome
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Gasbox Full Rigid Chopper Frame 1986-2003 Harley-Davidson Sportsters - 3" Up - Frisco Tank Mounts
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Lowbrow Customs 16 Piece Aluminum Wheel Axle Spacer Kit - 1.125 inch O.D. x 3/4 inch I.D.
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Mid-USA Rear Caliper Bracket for Rigid Models with 11-1/2 inch Rotors - 3/4" Axle - Chrome
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LePera Signature II Two Piece 2-Up Seat - Rigid Frame
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Haifley Seats King And Queen Seat - Black Pleated - 2004-2021 (Excl. 2007-09) Harley-Davidson Sportsters
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Performance Machine Performance Machine Classic 4 Piston Brake Caliper - Polished
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Cycle Standard Motorcycle Tire Inner Tube - 2.75 / 3.00-21 inch Center Metal Valve
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Tri-Spark Tri-Spark Classic Twin Electronic Ignition System for Triumph BSA Norton Twins And SIngles
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Prism Supply Co. Sling Shot Clutch Control - Harley-Davidson 5 & 6 Speed - Stainless Steel
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Lowbrow Customs T-Bars Handlebars - 8 inch Rise - 1 inch Diameter - Chrome
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Lowbrow Customs P-Nut Mid-Tunnel Gas Tank 1.8 gallon
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Gremlin Wiring The Sportster Treatment Custom Wiring Harness Kit 1999-2003 Harley-Davidson Sportster Models
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Lowbrow Customs Cloth Covered Wire - 16 gauge - sold by the foot - Assorted Colors Available
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Gasbox Steel 16 inch Fender for Vintage Style Tires
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V-Factor Motorcycle Parts MCM Slash Cut Drag Pipes 1986-2003 Harley-Davidson Sportster - Chrome
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Gasbox Dog Dish Air Cleaner - Harley CV / EFI 1991-2019
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Cannonball Heavy Duty Kickstarter Kit fits 1985-1998 Harley-Davidson 5-Speed Big Twin
1 review $2,196.55

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

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

Bates Baja 100 Tire 19" - 4.00-19 71T
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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 Narrow Rabbit Ears Handlebars - 1 inch - Chrome
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Cycle Electric Generator DGV-5000-L-BLK 12 Volt - Low Voltage - 1965-84 Harley-Davidson - Blacked Out
2 reviews $535.58 $573.32

Coker Tire Firestone ANS Motorcycle Tire 4.50-18
$300.98

Bob Newby Racing Belt Drive and Clutch for Triumph Unit 650 c.c. T120 TR6
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Lowbrow Customs Weld-On Upper Fender Mount Tab for Curved and Ribbed Motorcycle Fenders
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Lowbrow Customs Belt to Chain Conversion Kit Harley 883 Sportster 1995-2003 - Chrome Sprocket
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Mid-USA Four Piston Brake Caliper - Polished
4 reviews $259.95

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

Lowbrow Customs 39mm Tapered Fork Lowers - Aluminum
2 reviews $344.06

Lowbrow Customs 39mm Narrow Triple Trees Kit
3 reviews $449.99

Mid-USA 16 x 3.00 Chrome Complete Front / Rear Wheel fits Harley-Davidson Big Twins 1973-1984
15 reviews $202.75

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

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

Cycle Electric Rectifying Regulator CE-606- 2006-2008 Harley-Davidson FLH FLT
33 reviews $221.97 $237.61

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

Cycle Electric Stator CE-8012 for 2006 - 2016 Harley-Davidson FLH and FLT Models
40 reviews $165.80 $177.48

Gasbox Hi Lo Shotgun Exhaust Pipe Set 1986-2003 Harley-Davidson Sportsters
4 reviews $279.99

Cycle Standard Mini Ape Hanger Handlebars - 1 inch - 9 inch Rise - Chrome
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Cycle Standard Bates Style Rectangular Motorcycle Headlight - Clear Lens - Chrome
1 review $65.00

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

Morris Magneto MM74L Magneto for Alternator Big Twin Harley Davidsons 1974 - 1992 - Brushed Finish
2 reviews $1,942.38

S&S Cycle S&S Super E, B & G Master Carburetor Jet Kit - #11-7272
12 reviews $112.95

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

Biltwell Dual Cable Cast Whiskey Throttle - Polished Aluminum - 1 inch
23 reviews $99.95

James Gaskets 39mm Narrowglide Fork Seal Rebuild Kit 1988-Up Harley Sportster
21 reviews $26.09

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

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

Timken Neck Post Bearing & Race Set - Made in USA
18 reviews $28.14

V-Factor Motorcycle Parts Lever Action Starter Solenoid 1965-1986 Harley-Davidson Big Twin 4 Speed 1984-1988 Softail - Chrome
10 reviews $131.95

V-Factor Motorcycle Parts DIY 1-3/4 inch Builder Exhaust Kit - for your Chopper Bobber or Cafe Build
18 reviews $166.95

Gasbox Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 4 Speed - 3" Up - Frisco Tank Mounts - Horseshoe Oil Tank
$1,799.00

Gasbox Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 4 Speed - 3" Up - Sporty Tank Mounts - Horseshoe Oil Tank
$1,799.00

Kustom Tech DeLuxe 1 inch Master Cylinder Polished Aluminum & Brass
15 reviews $448.14

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

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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