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 Rubber-Mount Quickbob Gas Tank 1986-2003 Harley-Davidson Sportster
$407.51

Mid-USA Four Piston Brake Caliper - Black Anodized
3 reviews $275.00

Lowbrow Customs Shotgun Exhaust Pipes 1990-2003 Harley-Davidson Sportster XL Chrome
60 reviews $353.49

Old-Stf Cycle Centerline Adjustable Aluminum Transmission Plate - Harley-Davidson Big Twin 4 Speeds
5 reviews $249.00

Cycle Electric Generator DGV-5000L 12 Volt - Low Voltage - 1965-1984 Harley-Davidson
44 reviews $543.94 $582.26

Performance Machine Performance Machine Classic 4 Piston Brake Caliper - Polished
$385.43

Mid-USA Forward Controls 1936-1999 Harley-Davidson Big Twin - 5/8" Bore - Black Billet
1 review $383.40

Lowbrow Customs Weld-On Upper Fender Mount Tab for Curved and Ribbed Motorcycle Fenders
108 reviews $30.02

Lowbrow Customs Shotgun Exhaust Pipes 1990-2003 Harley-Davidson Sportster XL - Raw Steel
5 reviews $299.93

Lowbrow Customs Dished Clamp-On Steel Motorcycle Oil Tank for Harley Sportster Hardtails
19 reviews $267.79

Mid-USA Four Piston Brake Caliper - Polished
4 reviews $259.95

Gasbox 007 Stainless Air Cleaner for 1991-2022 Harley-Davidson CV Carburetor/EFI
39 reviews $99.95

Morris Magneto MM2 Magneto for 1971-1980 Harley-Davidson XL - Brushed Finish
$1,295.00

Cycle Standard Motorcycle Tire Inner Tube - 2.75 / 3.00-21 inch Center Metal Valve
28 reviews $24.28

American Prime Mfg. Brake/Mechanical Clutch Control Kit for 1 inch Handlebars - 11/16 inch Bore - Polished
1 review $366.14

FNA Custom Cycle Pop Top Oil Pressure Indicator
14 reviews $118.57

Tri-Spark Tri-Spark Classic Twin Electronic Ignition System for Triumph BSA Norton Twins And SIngles
17 reviews $327.06

Cycle Electric LeBeef Generator DGV-5000-L-CP 12 Volt - Low Voltage - 1965-1984 Harley-Davidson
$638.37 $683.35

Gasbox Steel 16 inch Fender for Vintage Style Tires
48 reviews $169.99

Lowbrow Customs Radius Breather Bolts for Harley-Davidson Evo - Chrome Plated
101 reviews $49.49

Belt Drives LTD. 8mm/1.5 inch Primary Belt Drive - Kick Start - 1979-E1984 Harley-Davidson Big Twins
$726.39 $764.62

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

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

Gasbox Chrome Square Top Sissy Bar - Flat Fender - Box Tail Light
5 reviews $189.95

Lowbrow Customs 16 Piece Aluminum Wheel Axle Spacer Kit - 1.125 inch O.D. x 3/4 inch I.D.
7 reviews $61.33

Cycle Standard Front Brake Master Cylinder Assembly - Chrome - Single Disc 1996-2017 Models (EXCEPT 15-17 Softail, 08-17 Dressers, Trike, 04-17 XL)
1 review $188.86 $230.05

Morris Magneto T5 Twin Cam Magneto for Harley Davidson - Brushed Finish
$2,453.41

Belt Drives LTD. 2" Open Belt Drive Kit - Polished - 1990-2006 Harley-Davidson FXST/FLST
2 reviews $2,958.01 $3,113.69

Prism Supply Co. Quick Stick Start Lever 2.0 1991-Up Harley-Davidson Sportster 1989-Up Big Twin - Matte Aluminum
6 reviews $119.99

Mid-USA Forward Controls 1936-1999 Harley-Davidson Big Twin - 5/8" Bore - Polished Billet
4 reviews $399.95

Gasbox Full Rigid Chopper Frame 1986-2003 Harley-Davidson Sportsters - 3" Up - Frisco Tank Mounts
5 reviews $1,199.00

Gasbox Full Rigid Chopper Frame 2004-2022 Harley-Davidson Sportsters - 3" Up - Sporty Tank Mounts
3 reviews $1,199.00

Lowbrow Customs Narrow Rabbit Ears Handlebars - 1 inch - Chrome
47 reviews From $143.17

Mid-USA 21 x 2.15 Black Complete Front Wheel fits Harley-Davidson Sportster XL & FX 1984-1999
13 reviews $334.00

Cycle Standard Braided Stainless Cut-To-Length Compression Brake Line Kit - Clear Coating
2 reviews $62.81

Cycle Standard 5 Stud Clutch Hub Assembly - Harley-Davidson Big Twins 1941-1984 OEM #37550-41B
6 reviews $114.25

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

Cycle Electric CE-8010-08 Stator Replacement for 2008-2017 Harley Dyna & Softail OEM #30017-08
22 reviews $163.88 $175.43

Belt Drives LTD. 2" SS Belt Drive - Without Cover - 1990-2006 Harley-Davidson FXST/FLST
$2,790.51 $2,937.38

Lowbrow Customs Belt to Chain Conversion Kit Harley 1200 Sportster 1995-2003 - Black Sprocket
44 reviews $167.99

Cycle Standard Front Brake Master Cylinder Assembly - Black - Single Disc 1996-2017 Models (EXCEPT 15-17 Softail, 08-17 Dressers, Trike, 04-17 XL)
$194.71

Drag Specialties 530 O-Ring Drive Chain - 130 Links includes Master Link
7 reviews $172.87

Cycle Standard Mini Ape Hanger Handlebars - 1 inch - 9 inch Rise - Chrome
40 reviews From $121.93

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

Lowbrow Customs Belt to Chain Conversion Kit Harley 1200 Sportster 1995-2003 - Chrome Sprocket
25 reviews $173.40

American Prime Mfg. Comp Master Ignition Advance Unit - 1970-Up Harley-Davidson Replaces OEM #3251770T
6 reviews $88.21

Cannonball Heavy Duty Kickstarter Kit fits 1985-1998 Harley-Davidson 5-Speed Big Twin
1 review $2,196.55

Lowbrow Customs Stingray Ribbed Steel Fender 6 inch Width
69 reviews $207.08

Mid-USA Front Caliper Bracket for Springer Models - Chrome
3 reviews $156.00

S&S Cycle HI-4N Ignition Module Kit - 1970-1999 Harley-Davidson Big Twins 1971-1990 XL
1 review $550.04 $599.95

Lowbrow Customs Weatherproof Starter Ignition Key Switch - Chrome Bezel
94 reviews $70.10

S&S Cycle Super E Carburetor Kit 1966-78 Harley-Davidson Shovelhead
4 reviews $729.73 $799.95

Bates Baja 100 Tire 19" - 4.00-19 71T
6 reviews $216.89

Cycle Standard 4-1/2 inch diameter Chrome Early Model Headlight
24 reviews $92.59

Dynatek Performance Electronics 2000I PC Programmable Electronic Ignition Kit for Harley-Davidsons - Includes Module and DC-6-5 Twin Fire II Mini Coil
2 reviews $557.00

Lowbrow Customs Belt to Chain Conversion Kit Harley Davidson Dyna Twin Cam 2006-2017 - Black Sprocket
15 reviews $207.99

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

LePera Signature II Solo Seat - Diamond - Rigid Frame
1 review $295.00

Lowbrow Customs Shotgun Exhaust Pipes 2004-21 Harley-Davidson Sportster XL Chrome
41 reviews $343.19

Cycle Standard 1936-1986 Harley-Davidson Big Twin 4 Speed Kickstarter Rebuild Kit
2 reviews $124.69

Mid-USA Rear Master Cylinder - 1987-2003 Harley-Davidson Sportster - Replaces OEM #42456-87C
15 reviews $112.70

Lowbrow Customs Straight Leg Bolt-On Hardtail Rear Frame Section for 1967-1978 Harley-Davidson Ironhead Sportster
17 reviews $405.59

EK Chains 530 ZVX3 Sealed Extreme Series X-Ring Chain - 120 Links - Gold
1 review $252.91 $271.95

Lowbrow Customs High Mids Foot Controls - Bolt-On Kit for 1991-2003 Harley-Davidson Sportsters
1 review $499.99

Prism Supply Co. Prism Supply Co. Box Chopper Tail Light - Polished
1 review $124.99

James Gaskets Top End Gasket Kit 1991-2003 Harley-Davidson Sportster XL 883/1200
5 reviews $124.86

Lowbrow Customs King P-Nut Frisco Gas Tank - 2.4 Gallon for 1986-2003 Harley Sportster
44 reviews $251.57

Mid-USA Hardbody Antique Style Springer Front End - Standard Length - Black
6 reviews $980.35

Lowbrow Customs T-Bars Handlebars - 12 Inch Rise - 1 inch Diameter - Black
1 review $144.14

Morris Magneto MM74L Magneto for Alternator Big Twin Harley Davidsons with Aftermarket Cases - Brushed Finish
$1,942.38

Shinko Motorcycle Tires Classic 240 Front Motorcycle Tire - 100/90-19 63H
7 reviews $119.99

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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