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

Colony #2141-2 Swingarm Covers 1986-1999 Harley-Davidson Softail - Plated
4 reviews $31.13

Colony #2122-2 Swingarm Covers 2000-2007 Harley-Davidson Softail - Chrome Plated
2 reviews $31.13

Colony #9781-5 Top Motor Mount Hardware Kit 1932-Up Harley-Davidson 45's - Parkerized
1 review $10.37

Colony #3050-2 Stem Nut Lockwasher Kit 1960-Up Harley-Davidson FL/FLH W/O Steering Damper
$15.52

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

Colony #3402-6 Sprocket Cover & Rear Master Cylinder Mounting Kit 1986-2003 Harley-Davidson XL - CAD Plated
2 reviews $7.73

Colony #2755-4 Rear Brake Caliper Mounting Allen Kit 2008-Up Harley-Davidson Softail/Dyna - Chrome Plated
$10.29

Colony #2600-2 Brake Caliper Bleed Screws 1983-2004 Harley-Davidson Big Twin 1983-2003 XL - Chrome Plated
4 reviews $10.29

Colony #3571-10 Disc Brake Rotor Allen Screw Set 1978-1982 Harley-Davidson FX/XL - Zinc Plated
2 reviews $15.43

Colony #3683-16 Lower Motor Mount Kit 1958-1965 Harley-Davidson OHV Big Twins - CAD Plated
$30.80

Colony #3578-28 Footboard Pad Rivets 1941-1965 Harley-Davidson All Models
$15.40

Colony #2920-2 Nut & Lock Kit 1936-Up Harley-Davidson Big Twin Kickstarter 1936-1979 Bg Twin 4 Speed Countershaft
5 reviews $7.70

Colony #7101-1 Motor Sprocket Nut 11/16-18 Thread - 1930-1954 Harley-Davidson Big Twins
$15.40

Colony #2277-10 12 Point Sprocket Bolt and Washer Kit 1979-1990 Harley-Davidson XL 1973-1992 Big Twin - Chrome Plated
1 review $30.79

British Standard Shifter Lever / Center Stand Rubber for Triumph Motorcycles
17 reviews $7.69

British Standard Tapered Kick Start Cotter Pin for Triumph Motorcycles - Oversized
11 reviews $15.35

Drag Specialties Organic Rear Brake Pads L1987-99 H-D XL 91-98 Dyna Glide 84-97 FXR 84-E87 FXST/FLST
$30.58

Cycle Standard 5 Hole Chrome Derby Cover for Harley-Davidson Big Twins
$30.58

Reverb Inc. Reverb Vintage Style Cable Wrap - Red/White
5 reviews $30.53

Cycle Standard Kickstand Bumper Rubber - 1999-2006 Harley-Davidson Touring Models OEM #50245-99A
6 reviews $7.58

Colony #2783-5 Starter Pedal Axle Kit 1916-1962 Harley-Davidson - Parkerized
$30.25

Lowbrow Customs Lowbrow Customs Horseshoe Oil Tank Upper Tab Mounting Kit - 1982-2003 Sportster Hardtail
6 reviews $15.09

Lowbrow Customs 7mm Cloth 90 Degree Spark Plug Wire Sets - Oak w/ Red and Black Tracers
4 reviews $30.02

Colony #3642-2 Buddy Seat Auxiliary Spring Clip - Heavy - 1936-1964 Harley-Davidson Big Twins - Parkerized
$30.00

Cycle Standard 41mm Fork Seal Rebuild Kit - 1977-1984 Harley-Davidson FL 1980-83 FXWG FLT
$15.00

Colony #2928-30 Clutch Dome Cover Retainer Kit 1954-1970 Harley-Davidson KH/XL
1 review $30.00

Colony #2625-30 Rear Fender Support Mounting Kit 1958-1980 Harley-Davidson FL/FLH - CAD Plated
5 reviews $30.00

Colony #8756-30 Primary Cover Allen Screw Kit 1936-1984 Harley-Davidson Big Twin - Chrome Plated
$30.00

Lowbrow Customs AMF Grips - Natural Gum - 1 inch
7 reviews $14.99 $19.99

Colony #7812-12 Inner Primary Mounting Kit - 1955-1964 Harley-Davidson Panhead
$29.98

Cycle Craft #42 Pilot Jet - 1988-2006 Keihin CV Carburetor
3 reviews $5.99

Gasbox Side Mount Headlight Bracket Set for Harley 35mm Narrow Glide Front Forks
1 review $29.95

British Standard 1/4 inch BSP Petcock Fuel Valve Main For Triumph 650 750 Norton 750 850
3 reviews $29.79

Colony #9946-20 Cam Cover Mounting Allen Kit 1999-Up Twin Cam Dyna/FLT 2000-Up Softail - Chrome Plated
1 review $14.89

Colony #2137-4 Handlebar Riser Hex Bolt Kit 1/2-13 x 3" - Chrome Plated
5 reviews $14.89

Colony #2136-4 Handlebar Riser Hex Bolt Kit 1/2-13 x 2-3/4" - Chrome Plated
1 review $14.89

Colony #2131-4 Handlebar Riser Allen Bolt Kit 1/2-13 x 3-3/4" - Chrome Plated
$14.89

Colony #9617-18 Jiffy Stand & Foot Clutch Lever Bracket Mounting Kit 1936-1978 Harley-Davidson Big Twin - Chrome Plated
$29.78

Colony #9851-5 Primary Cover Screw Kit 1957-1966 Harley-Davidson XL/XLH - CAD Plated
$14.89

Colony #8783-8 Cam Cover Allen Screw Kit 1971-1985 Harley-Davidson Sportster - Chrome Plated
1 review $14.89

Colony #8837-10 Sprocket Nut & Bolt Kit Cap Head 1973-Up Harley-Davidson Big Twin/XL - Spoked Wheel - Chrome Plated
$29.70

Colony #3534-22 Rear Fender Rail Screw & Acorn Nut Kit 1980-1986 Harley-Davidson FXWG - Chrome Plated
$29.70

Colony #2680-4 Handlebar Riser Mounting Kit 1949-1959 Harley-Davidson Big Twins - CAD Plated
$29.70

Colony #2128-5 Gas Tank Acorn Nut Mounting Kit 1984-1999 Harley-Davidson Softail - Chrome Plated
$14.83

Drag Specialties Shifter Linkage - Chrome - 1982-94 99-00 Harley-Davidson FXR
$29.63

Cycle Standard 10 Hole Clutch Pressure Plate 1941-1984 Harley-Davidson Big Twins
1 review $14.78

Cycle Standard Steel Clutch Plate Set 1991-Up Harley-Davidson Sportster 90-97 Big Twin
$29.49

Colony #8163-3 Front Axle Nut Kit 1946-1971 Harley-Davidson Big Twins - CAD Plated
$14.74

Colony #8112-20 Transmission Side & Clutch Arm Nut Kit Harley-Davidson Big Twin 4 Speeds To 1984 - Chrome Plated
3 reviews $14.74

Kibblewhite Precision Machining Clutch Springs (set of 3) 1963-1983 Triumph 650 Twins OEM # 57-1830
8 reviews $14.70

Colony #8474-8 Cylinder Base High Crown Cap Nut Set 1978-1984 Harley-Davidson Shovelhead - Chrome Plated
$29.34

Colony #8007-2 Intake Manifold Nuts 1936-1939 61 c.i. Knucklehead & 1930-1948 Sidevalve (Except 45's) - CAD Plated
$29.34

Cycle Standard Replacement Oil Tank Cap Harley-Davidson OEM #62644-84T
7 reviews $14.54

Colony #3544-3 Oil Line Nuts 1915-1964 Harley-Davidson All Models OEM #3581-15 - CAD Plated
$14.52

Colony #3265-1 Upper Bearing Dust Shield 1949-Up Harley-Davidson Big Twin 4-Speed Pre-2017 Softail Pre-2005 Dyna/FXR to 2005 1980-2013 Touring 1982-2003 Sportster - Zinc Plated
5 reviews $7.26

Colony #2513-3 Clutch Drive Hub Stud Nut Kit 1947-1984 Harley-Davidson Big Twin 1947-1973 45's - Parkerized
7 reviews $7.26

Lowbrow Customs Weld-On 5 inch Trailer Fender Brace / Mount - Wide Rigid Frame - Harley-Davidson Shovelhead Sportster etc
8 reviews $29.00

Cycle Standard Shift Lever 2006-2011 Harley-Davidson Dyna - Black - OEM# 33735-09
$28.99

Colony #2018-8 Head Bolt Washers 1984-Early 1985 Harley-Davidson Big Twin/XL - CAD Plated
$28.97

Colony #8228-2 Intake Manifold Nuts 1937-1973 Harley-Davidson 45's - CAD Plated
$28.97

Drag Specialties 530 Series O-Ring Replacement Rivet Style Master Link
$9.63

Colony #2106-4 Countersunk Gas Tank Mounting Kit 1998-Up Harley-Davidson FLT - Chrome Plated
$14.34

Colony #9664-8 Linkert Carb Mounting Screws Harley-Davidson OEM #27424-48 - Parkerized
4 reviews $9.56

Colony #8212-3 Oval Head Screw Kit 5/16-24 for Harley-Davidsons - Chrome Plated
$9.56

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

Colony #2744-10 Center Stand Mounting Kit 1958-1981 Harley-Davidson FL/FLH
2 reviews $28.60

Colony #8846-2 Shift Gate Clamp Nut 1916-1935 Harley-Davidson 1936 VL - Chrome Plated
$28.60

Colony #8706-6 Tappet Oil Screen/Oil Pump Check Valve/Relief Valve Plug Set 1970-1980 Harley-Davidson Big Twin - Chrome Plated
1 review $28.60

Colony #8601-8 Hi-Torque Cylinder Base Nut Set Harley-Davidson Big Twin Pre-Evo - Black
2 reviews $28.60

Cycle Standard 28 degree 7/16 inch/14mm Compression Banjo Fitting - Stainless
$14.29

Colony #9783-4 Headlight Visor Mounting Allen Bolt Kit 1959-Up Harley-Davidson XL/FX/FXR - Chrome Plated
3 reviews $4.76

Colony #2431-9 Outer Chain Guard Mounting Screw Kit 1951-1973 Harley-Davidson Servi-car - Parkerized
2 reviews $28.47

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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