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.

Custom Motorcycle Parts

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BEST SELLING BRANDS

TOP Custom Motorcycle Parts

Progressive Suspension 412 Series 11" Shocks Chrome With Full Covers 1973-1986 Harley-Davidson Shovelheads
$454.95

Progressive Suspension 412 Series 11" Shocks Chrome With Short Covers 1973-1986 Harley-Davidson Shovelheads
$379.95

Progressive Suspension 412 Series 13.5" Shocks Chrome With Short Covers 1963-1978 Harley-Davidson XL
$379.95

Progressive Suspension 412 Series 14.25" Shocks Chrome With Short Covers 1963-1978 Harley-Davidson XL
$379.95

Til Death Cycles TDC Oversize Seat Mount Nut Kit
$25.82

Sully's Customs Skinny Style Seat - Black Diamond - 1982-2003 Harley-Davidson Sportsters
2 reviews $214.99

Colony #3781-10 Electric Terminal Plate 1954-1977 Harley-Davidson XLH 1970-1978 XLCH
$23.00

Colony #3791-4 3/4 OD x 5/16" ID x 1/2" Spacers Harley-Davidson OEM #4 52104-38/3209-38 - 4 Pack - CAD Plated
$10.89

Colony #3789-10 Summer Windshield Mounting Kit 1941-1945 Harley-Davidson - Parkerized
$26.00

Colony #3783-4 Kick Starter Tripper Bolt/Nut Kit 1926-1940 Harley-Davidson 45's - Parkerized
$23.18

Colony #3782-10 Terminal Board Expansion Nut/Screw Kit 1954-1978 Harley-Davidson XL/XLH/XLCH
1 review $14.30

Colony #3780-18 Rocker Box Flange Nut Kit 1966-1983 Harley-Davidson Shovelhead - Chrome Plated
$25.00

Colony #3776-2 Front Axle Nuts 1916-1923 61" Harley-Davidson Twins - Nickel Plated
$16.50

Colony #3774-1 Oil Tank Drain Plug 1936 61" Harley-Davidson - Nickel Plated
$25.00

Colony #3773-2 Front Axle Nuts 1922-1923 Harley-Davidson 74" Twins 1924-1927 All Twins - Nickel Plated
$16.50

Colony #3772-2 Spark Plug Hole Caps 1926-1934 Harley-Davidson Singles 1929-1955 Flatheads All Knuckleheads
$16.50

Colony #3771-20 Rocker Cover Allen Screw Kit 2017-Up Harley-Davidson Touring Models - Chrome Plated
$44.44

Colony #3769-7 Right Side Transmission Cover Support Bracket Mount Kit 1965-1972 Harley-Davidson FL/FLH
$17.60

Colony #3767-15 Sprocket Bolt/Nut/Washer Kit 1985-1992 Harley-Davidson Big Twins - Zinc Plated
$27.50

Colony #3763-5 Generator Strap Rebuild Kit 1930-1957 Harley-Davidson 45's/VL/Knucklehead/Panhead
$23.00

Colony #3762-5 Dash Cover Mounting Kit 1936-1946 Harley-Davidson Twins - Parkerized
$4.95

Colony #3758-3 Chain Oiler Adjusting Screw Kit L1950-1964 Harley-Davidson OHV 1958-1969 Servi-car - Parkerized
$12.09

Colony #3755-3 Chain Oiler Adjusting Screw Kit L1972-E1983 Harley-Davidson FL/FX
$12.09

Colony #3562-1 Stem Crown Nut /Dust Shield 1939-1948 Harley-Davidson Big Twin Springer
$60.50

Drag Specialties Steel Clutch Plate Set 2017-2023 Harley-Davidson M8 2013-2017 Twin Cam CVO/SE 2014-2023 FL Trike
$37.82 $50.42

Drag Specialties Steel Clutch Plate Set 1998-1999 Harley-Davidson Big Twin 1999-2017 Twin Cam
$30.86 $41.15

Drag Specialties Aramid Fiber Clutch Plate Set 1998-1999 Harley-Davidson Big Twin 1999-2017 Twin Cam
$101.93 $135.91

Drag Specialties Steel Clutch Plate Set L1984-1990 Harley-Davidson XL
$27.51

Drag Specialties Aramid Fiber Clutch Plate Set L1984-1989 Harley-Davidson XL
$81.85 $116.55

Bare Knuckle Performance Jane Doe Jockey Shift Knob - 1.75 inch Long
$69.00

Bare Knuckle Performance Antihero Stainless Steel Rear Brake Rotor - 11.5 inches 2000-Up Harley-Davidson Models
$249.00

Bare Knuckle Performance Antihero Stainless Steel Front Brake Rotor - 11.5 inches 2000-Up Harley-Davidson Models
$249.00

Bare Knuckle Performance Antihero Stainless Steel Rear Brake Rotor - 11.5 inches Pre-1999 Harley-Davidson Models
$249.00

Bare Knuckle Performance Antihero Stainless Steel Front Brake Rotor - 11.5 inches Pre-1999 Harley-Davidson Models No Speedo Drive
$249.00

Bare Knuckle Performance Antihero Stainless Steel Front Brake Rotor - 11.5 inches Pre-1999 Harley-Davidson Models with Speedo Drive
$249.00

Bare Knuckle Performance Sprung Weld-On Chain Tensioner
$179.00

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

Bare Knuckle Performance Sissybar Mounting Kit - 3/8-16 Thread - Mild Steel
$39.00

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

Bare Knuckle Performance SS2 Weld-On Complete Seat Spring Mounting Kit - Flat Bottom
$55.00

Bare Knuckle Performance SS2 Solo Seat Springs - Barrel Style - 3 inch Stainless Steel
$34.00

Bare Knuckle Performance 49mm Mid Glide "The Clinch" Fork Brace - Gloss Black
$324.00

Bare Knuckle Performance 49mm Mid Glide "The Clinch" Fork Brace - Raw
$299.00

Bare Knuckle Performance 39mm Narrow Glide "The Clinch" Fork Brace - Gloss Black
1 review $299.00

Bare Knuckle Performance 39mm Narrow Glide "The Clinch" Fork Brace - Raw
$274.00

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

Gasbox Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 5 Speed - 3" Up - Sporty Tank Mounts - Horseshoe Oil Tank
1 review $1,799.00

Gasbox Full Rigid Frame 1936-1999 Harley-Davidson Big Twin 5 Speed - Sporty Tank Mounts - Horseshoe Oil Tank
$1,799.00

Gasbox Full Rigid Frame 1936-1999 Harley-Davidson Big Twin 4 Speed - Frisco Tank Mounts - Horseshoe Oil Tank
4 reviews $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

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

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

Cycle Electric LeBeef Generator DGV-5000-CP 12 Volt - 1965-1984 Harley-Davidsons
$638.37 $683.35

Boyer Bransden Boyer Bransden Dual Lead 12V Coil British Twins with Electronic Ignition
$140.58

Airspeed Cycles T-Bar Handlebars - 10 inch Rise - 1 inch - Stainless Steel
2 reviews $235.00

Cycle Standard Inner Shift Lever 1982-Up Harley-Davidson FL Models - Black - OEM #33718-82B
$25.97

Cycle Standard Replacement Chain Conversion Sprocket - Chrome - 53 Tooth - Harley-Davidson Sportster 2000-Up Dyna 2006-Up
$70.54

Cycle Standard Transmission Sprocket .5" Offset - 25 Tooth - 2006-2017 Harley-Davidson Dyna 2007-Up Softail
$65.85

Lowbrow Customs Lowbrow Customs Spark Plug Wire Set 1999-2017 Harley-Davidson FXD 2000-2017 FXST/FXST
$22.99

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

Lowbrow Customs Throttle Housing 1981-1995 Harley Thread-In Single Cable - Brass - 1 inch
5 reviews $128.53

Prism Supply Co. Prism Supply Co. 2-Piece Tail Light - Brass
1 review $104.99

Prism Supply Co. Prism Supply Co. 2-Piece Tail Light - Brushed Aluminum
$94.99

Prism Supply Co. Prism Supply Bell Tail Light - Gloss Black
$104.99

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

Prism Supply Co. Prism Supply Co. 1.85 inch Speedster Tail Light - Gloss Black
2 reviews $104.99

Prism Supply Co. Prism Supply Co. 1.25 inch Speedster Tail Light - Gloss Black
1 review $104.99

Prism Supply Co. Prism Supply Co. Steel Flat Tail Light - Weld-On
$89.99

Prism Supply Co. Universal Fender Mounting Bracket - Prism Supply Co. Round Tail Lights
$30.99

Prism Supply Co. Weld-On Stainless Steel Light Mount With License Plate Bracket - Prism Supply Co. PS-41 Tail Light
$33.99

Prism Supply Co. Weld-On Steel Light Mount - Prism Supply Co. Box Chopper Tail Light
$19.99

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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