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

Gasbox Upswept Exhaust Pipe Set for 1970-1984 Harley-Davidson Shovelhead Rigid Applications
1 review $329.95

Performance Machine Classic 5 Spoke One-Piece Brake Rotor - 11.5 inch - Front
$164.95

Cycle Standard Front Motor Mount 1982-94 Harley-Davidson FXR 80-08 FLH FLT
$36.51

Lowbrow Customs Louvered Air Cleaner for S&S Super E / G Carburetors - Chrome
37 reviews $81.78

Lowbrow Customs Throttle Housing 1996 & up Harley Push-In Dual Cable - Aluminum - 1 inch
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Lowbrow Customs Rear Caliper Bracket for Rigid Models with 11-1/2 inch Rotors - 1" Axle - Raw
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Drag Specialties Skeleton Kickstarter Pedal - Brass
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Arlen Ness Big Sucker Stage 1 Air Filter Kit - Chrome - 1999-2017 Harley-Davidson Twin Cam
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Lowbrow Customs Front Solid Motor Mount Kit for 2004 - Up Harley-Davidson Sportster XL
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Gates Corporation 3/8 inch Black Fuel / Oil Line - By The Foot
15 reviews From $14.75

Goodridge P599-03C 90 Degree 3/8 inch/10mm Banjo Fitting - Stainless Steel
8 reviews $17.95

Lowbrow Customs 39mm Fork Shrouds - Black - 1987-Up - Harley-Davidson Sportsters
53 reviews $128.90

Lowbrow Customs Domed Screw-In Gas Cap for Harley-Davidson 1996 & later - Aluminum
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Old-Stf Cycle Shovelhead Rocker Box Split Oil Lines - Brass
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Haifley Seats Bates Style Lil Guy Pillion P-Pad - Tuck-n-Roll
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Led Sled Customs 6 inch Flat Top Fender for 16 inch Stock Style Dunlop Tires
24 reviews $160.00

Cycle Standard CV Carburetor Vacuum Piston Replaces Harley-Davidson OEM #27585-88
5 reviews $39.86

Lowbrow Customs Mounting Kit for WX Gas Tanks - 1985-1999 Harley-Davidson Softails
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Lowbrow Customs Throttle Housing 1996 & up Harley Push-In Dual Cable - Black - 1 inch
18 reviews $105.15

EK Chains 530 ZVX3 Sealed Extreme Series X-Ring Chain - 150 Links - Gold
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Gasbox Antigravity 12 Cell Universal Battery Box - Tumbled Aluminum
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Lowbrow Customs Manta Ray Smooth Steel Fender 7 inch Width
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Pro One Performance Products Hidden/Internal Fork Stop Kit 1989-1999 Harley-Davidson Softail
1 review $104.45

Lowbrow Customs Dished Screw-In Gas Cap for Harley-Davidson 1996 & later - Brass
16 reviews $89.06

Timken Harley Timken Wheel Bearings - OEM #9033 & 9052 Replacement
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James Gaskets Primary Cover & Inspection Cover Gasket Kit 8-Hole Primary Cover 1970-1982 Harley-Davidson Shovelhead
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Shinko Motorcycle Tires Classic 240 Double Whitewall Front/Rear Motorcycle Tire - MT90-16 74H
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Cycle Standard Fat Bob Rear Fender - 1994 - 2003 Harley Davidson Sportster XL Models
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British Standard Triumph Unit 650 Primary Cover Bonneville Tiger Trophy OEM #57-1727
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Bates S&S Super E/G Carburetor Adapter for Bendix Style Oval Harley Air Cleaners
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Lowbrow Customs Shorty Front Fender - Harley-Davidson 1973-up XL FX FXR 35mm 39mm Narrow Glide Front Forks - OEM #59031-83
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Shinko Motorcycle Tires Super Classic 270 Front/Rear Motorcycle Tire - 4.00-18 64H
3 reviews $153.34

Cycle Standard Chrome 12V Square Coil 1948-60 Harley-Davidson Big Twins
$122.59

Cycle Standard Nose Cone Cam Gear Cover - Chrome - 1993-99 Harley-Davidson Big Twin
3 reviews $153.10

Goodridge 35 Degree 3/8 inch/10mm Banjo Fitting - Ebony
8 reviews $15.95

Cycle Electric Stator CE-9902 for 1999-2003 Dyna and 2000 Softail Harley-Davidsons OEM #29951-99
7 reviews $121.18 $129.72

Cycle Standard Replacement Chain Conversion Sprocket - Black - 55 Tooth - Harley-Davidson Sportster 2000-Up Dyna 2006-Up
$75.69

Prism Supply Co. Bristol Breather - S&S Super E/G Carburetor - Tumbled
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Cycle Standard Mustang Gas Tank - Single Filler - 3.3 Gallon
6 reviews $201.66

Cycle Standard 22mm Petcock Round Body Chrome Harley-Davidson Style - Left Side Position
21 reviews $75.15

Cycle Electric Alternator Kit CE-94T-15 90 Series 56 Amp 2014-2016 Harley-Davidson FLH/FLT - Water Cooled
1 review $599.97 $642.25

Performance Machine Vintage 4 Piston Caliper 125 X 4R - Chrome
$599.95

Prism Supply Co. Prism Supply Co. 1.85 inch Speedster Tail Light - Brushed Aluminum
1 review $99.99

Gasbox Strong Arm Top Motor Mount With Crank Key Mount 1948-1984 Harley Big Twins
5 reviews $74.95

Cycle Standard 3/8 inch NPT Petcock 90 Degree Outlet
19 reviews $39.93

Lowbrow Customs Cloth Covered Wire - 12 gauge - sold by the foot - Assorted Colors Available
32 reviews From $15.62 $31.24

Podtronics Regulator/Rectifier - Single Phase With Built in Capacitor - Triumph / BSA
18 reviews $99.64

LCFabrications "The OG" Clutch Switch Pod Delete - Black - for Harley-Davidson
28 reviews $35.00

Prism Supply Co. Motor Mount Mid-Pegs for Harley-Davidson Big Twins - Stainless Steel
$84.99

Cycle Standard Motorcycle Tire Inner Tube - 4.00 / 4.50-18" Center Metal Valve
13 reviews $22.86

Prism Supply Co. Heritage Aluminum Foot Pegs
2 reviews $98.99

Cycle Standard Motorcycle Mirror Clamp - Chrome - for 1 inch Handlebars
18 reviews $23.71

Cycle Standard Choke Knob Enricher for Harley-Davidson S&S Super E and G Carburetors - Brass
8 reviews $53.64

Red Fox Enterprises Glass License Plate Round Reflector - Red
13 reviews $14.00

Bar-None Moto BNM Bolt On Sissy Bar For Rogue Fender - 1958-1984 Harley-Davidson Panhead/Shovelhead
5 reviews $293.54

Cycle Standard 3 Stud Clutch Hub Assembly - Harley-Davidson Big Twins 1941-1984 - OEM #37550-41B
15 reviews $117.39

Cycle Electric Alternator Kit CE-94T-12 90 Series 56 Amp 2011-2013 Harley-Davidson FLH/FLT
$586.80 $628.15

Lowbrow Customs Brass Exhaust Tips for 1.75 inch OD pipes
45 reviews $65.20

Parts Unlimited AGM YTZ-12S Maintenance Free Battery - For Electric Start Motorcycles
1 review $39.54

Cycle Standard Fat Bob Steel Fender-Left Side Chain Relief
25 reviews $83.59 $114.08

Cycle Standard 1.7 inch Rise Forged Aluminum Handlebar Risers for Harley-Davidson - Chrome
10 reviews $64.97

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

EMGO Triumph 650 c.c. 1963 - 1972 Complete Engine Gasket Kit
39 reviews $116.16

Monster Craftsman Powell Peralta Clamp on Chain Tensioner - 1 inch Tubing
$145.00

Cycle Standard Complete Front Rubber Motor Mount Kit 2004-Up Harley-Davidson Sportsters
1 review $192.96

Mid-USA Dual Piston Brake Caliper - Polished
$192.50

Motone Screw-In Billet Gas Cap for 1996 & later Harley-Davidson - Vented - Satin Brass
1 review $82.47 $102.22

Unity Manufacturing Rear Brake Caliper Bracket for Swingarm Harleys - 11.5" Rotor - 3/4" Axle - Raw
$115.00

Cycle Standard Grooved Stainless Steel Hidden/Internal Stop Fork Neck Cup Kit 1949-1987 Harley-Davidson Big Twins
1 review $114.71

Coker Tire Firestone ANS Motorcycle Tire 4.00-18
$286.38

Trader Cody's Choppers Rotary Top Shift Lever 1979-1986 Harley-Davidson Transmissions 4 Speeds - Stainless Steel
3 reviews $30.00

Hawg Supply Watson 4" Air Cleaner S&S Super E/G Carburetor - Brushed Aluminum
$189.99

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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