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 Chrome Kick Return Spring - 1936 - 1984 Harley Knucklehead Panhead Shovelhead #33085-3
4 reviews $26.08

Bates Springer Riser Studs M20 x 1.5 x 1/2-13 inch thread
3 reviews $39.06

Cycle Standard Throttle Idle Cable OEM #56355-96A Harley Dyna 1996-2008 +4 inch Extended
1 review $39.03

Bare Knuckle Performance SS2 Weld-On Solo Seat Spring Mounts - Short
$39.00

Colony #3319-1 Aluminum Axle Spacer Stock 5 inch x 5/8 inch I.D.
$19.36

Colony #2342-18-P Primary Cover Smooth Allen Screw Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
1 review $38.59

Colony #8919-19 Primary Cover Chrome Allen Head Screw Kit 1989-2006 Harley-Davidson Softail 1991-2005 Dyna - Chrome Plated
2 reviews $38.59

Mooneyes Glitter Dice License Plate Bolts - Red
5 reviews $15.40

Mooneyes Glitter Dice License Plate Bolts - Green
5 reviews $15.40

Colony #9009-5 Linkert Carb Support Bracket 1941-1953 Harley-Davidson OHV OEM #27431-41 - Parkerized
$19.25

Goodridge 30338TC-CL Universal Braided Stainless Brake Line - 38" - Clear Coated
3 reviews $76.95

Colony #9662-1 Gas Strainer Assembly 1950-1965 Harley-Davidson Big Twins - CAD Plated
2 reviews $76.76

Colony #9660-1 Gas Strainer Assembly 1942-1949 Harley-Davidson Twins - CAD Plated
3 reviews $76.76

Colony #8220-20 Head Bolt Kit 1940-1947 Harley-Davidson Knucklehead - Chrome Plated
1 review $76.76

Blue Streak High-Performance Condenser - 1970-79 Harley-Davidson
$10.95

Drag Specialties Universal 7 inch Battery Cable
$25.39

British Standard Throttle Cable 42" 1968-72 Triumph Bonneville T120R 1973-75 T140V Made in UK OEM #60-1819
2 reviews $38.04

Cycle Standard Throttle Idle Cable OEM #56355-96A Harley Dyna 1996-2008
1 review $38.01

Colony #9505-2 Handlebar Plunger 1940-1948 Harley-Davidson 45 Solo/Servicar OEM# 3316-36
$38.00

ODI Vans V-Twin Lock-On TBW Grips by ODI - Black/Silver - 1"
$75.95

ODI Vans V-Twin Lock-On Cable Throttle Grips by ODI - Dark Red/Red Anodize - 1"
$75.95

Cycle Standard Shift Lever - 1974-1984 Harley-Davidson FL 1980-1986 FXWG (With Splines) - Chrome - OEM #34606-74
$25.27

Cycle Standard Replacement Chain Conversion Sprocket - Chrome - 52 Tooth - Harley-Davidson Sportster 2000-Up Dyna 2006-Up
$75.48

Lowbrow Customs Rigid Frame Mounting Bracket for Shotgun Exhaust Pipes - 1990-2003 Harley-Davidson Sportster XL
$25.16

Lowbrow Customs Axle Spacer Kit for Lowbrow Ribbed Spool Wheel - 35mm Single Disc Showa & Kayaba Forks
$25.16

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

Colony #9418-19 Transmission Mounting Kit 1965-Early 1977 Harley-Davidson Big Twin - Chrome Plated
3 reviews $37.66

Cycle Standard Replacement Dished Sprocket - Chrome - 49 Tooth - 1973-1985 Harley-Davidson Big Twin 1979-81 XL
$75.05

Hawg Supply "Milled" 4-Speed Clutch Pressure Plate
$74.99

Gasbox Strong Arm Top Motor Mount - 1984-1999 Harley-Davidson Big Twin Evolution
$74.95

Lowbrow Customs AMF Grips - White - 1 inch
3 reviews $14.99 $19.99

Colony #7708-1 Bronze Seat Post 1936-1957 Harley-Davidson Big Twins
4 reviews $24.98

Colony #9692-4 Rear Axle Nut and Lock Kit - 1930-1972 Harley-Davidsons Knucklehead/Panhead/Shovelhead - Parkerized
3 reviews $24.98

Cycle Standard Throttle Idle Cable OEM #56415-06 Harley Dyna 2006-2017 - Blacked Out
1 review $24.96 $35.66

Goodridge Universal Braided Stainless Brake Line - 11" - Ebony
2 reviews $24.95

Gasbox Weld-On Vertical License Plate Bracket for Model A Style Light
4 reviews $24.95

Gasbox Weld-On Vertical License Plate Bracket
4 reviews $24.95

Cycle Standard Replacement Chain Conversion Sprocket - Black - 48 Tooth - Harley-Davidson Sportster 2000-Up Dyna 2006-Up
$74.78

Cycle Standard Replacement Dished Sprocket - Black - 51 Tooth - 1973-1985 Harley-Davidson Big Twin 1979-81 XL OEM #41470-73
$74.78

Cycle Electric Shim Kit CE-8120 for CE-32A Alternators on Harley-Davidsons
3 reviews $24.84

Motone Bolt-Down Billet Adapter for 2.5" Monza Gas Cap
1 review $37.19 $46.19

PanAm Oils Inc. Oil Pressure Gauge 0-60 psi - Black
9 reviews $37.15

Colony #7112-19 Transmission Side Cover & Clutch Arm Acorn Nut Kit - 1936-1984 Harley-Davidson Big Twin 4 Speeds - Chrome Plated
3 reviews $24.71

British Standard Throttle Cable 1968-1970 Triumph TR6 Made in UK OEM #60-0746
$37.04

Bare Knuckle Performance Sissybar Mounting Kit - 5/16-16 Thread - Mild Steel
1 review $37.00

Lowbrow Customs Solo Seat Springs - Barrel Style - 4 inch Black
24 reviews $24.66

Goodridge 30334TC-CL Universal Braided Stainless Brake Line - 34" - Clear Coated
$73.95

Cycle Standard Clutch Cable OEM #38621-86A 1986-2003 Harley-Davidson 1100 1200 Sportster XL +8 inch Extended
$36.91

Cycle Standard Throttle Cable OEM #56324-81C Harley Sportster XL 1981-1985
$24.60

Lowbrow Customs Solo Seat Springs - Barrel Style - 4 inch Chrome
29 reviews $24.57

Lowbrow Customs Hairpin Style Solo Seat Springs - 2-1/2 inch Black
12 reviews $24.55

British Standard Webco Ribbed aluminum Points Cover Triumph 650 750 Motorcycles # 70-8737 bobber
9 reviews $73.59

Cycle Standard O2 Sensor - Front - 2014-2017 Harley-Davidson Sportster OEM #32700026
$73.49

Colony #2433-18 Sidecar Body Support Rods Repair Kit 1941-1993 Harley-Davidson
1 review $73.37

Drag Specialties Clutch Cable OEM #38599-83A Harley-Davidson FXST 1987-1999
$73.09

James Gaskets Primary Cover Gasket 1977-1990 Harley-Davidson XL
$12.18

Goodridge 30332TC-CL Universal Braided Stainless Brake Line - 32" - Clear Coated
2 reviews $72.95

Colony #2271-8 Front Fender Allen Mounting Kit 1984-Up Harley-Davidson Sportster - Chrome Plated
7 reviews $10.42

Cycle Standard Brake Lever - Chrome - 1980-2003 Harley-Davidson XL OEM #42459-80B
$72.90 $76.38

Cycle Standard Dragton II Air Cleaner - Chrome - Fits Bendix / Zenith, Keihin (except CV) Carbs
15 reviews $72.80

Colony #8716-1 Fork Tube Plug 1978-Up Harley-Davidson Wide Glide - Chrome Plated
$24.26

No School Choppers 1933 - 1936 Ford Duolamp Tail Light Replacement Glass Lens - Red
3 reviews $24.20

Colony #2313-10 10mm Copper Brake Line Banjo Bolt Crush Washers Harley-Davidson OEM #41732-04 - 10 pack
5 reviews $14.52

Colony #2206-10 10mm Copper Brake Line Banjo Bolt Crush Washers OEM #41731-82A - 10 pack
4 reviews $14.52

Colony #8715-4 Rear Axle Nut & Washer Kit 1973-Up Harley-Davidson Big Twin 1979-Up XL - Chrome Plated
1 review $18.15

Lowbrow Customs Classic Grips - Natural Gum - 1 inch
18 reviews $18.15

Cycle Standard Throttle Idle Cable OEM #56309-96 1996-2001 Harley-Davidson Sportster XL +8 inch Extended
$36.29

Cycle Standard Clutch Cable OEM #38699-04 2004-Up Harley-Davidson Sportster XL +8 inch Extended
$72.58

James Gaskets Primary Cover Gasket 1983-1993 Harley-Davidson Softail & Dyna Models
$36.23

Lowbrow Customs 8mm Cloth Straight Spark Plug Wire Sets - Black with Orange Tracers
2 reviews $36.03

Cycle Standard Clutch Cable OEM #38666-00 Harley Dyna 2000-2005 +4 inch Extended
1 review $71.91

Cycle Standard Replacement Dished Sprocket - Black - 49 Tooth - 1973-1985 Harley-Davidson Big Twin 1979-81 XL
$71.89

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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