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

Lowbrow Customs Aluminum Gas / Oil Filler Cap with Weld-In Steel Bung - Unvented
4 reviews $43.59

Colony #2961-3 Timer Clamp Kit 1966-1970 Harley-Davidson XLH 1970 XLCH - Zinc Plated
$10.89

Colony #3118-3 Sprocket Nut Lockplate Harley 93-06 Softail Touring 93-05 Dyna — Colony #3118-3 Sprocket Nut Lockplate 1993-2006 Harley-Davidson Softail/Touring 1993-2005 Dyna
$14.51

Colony #9634-4 Oil Pump Check & Relief Valve Plugs 1981-Up Harley-Davidson FL/FX - Chrome Plated
1 review $21.73

Colony #8937-3 Pivot Bolt Washer & Spacer 1973-1978 Harley-Davidson XL - CAD Plated
$21.73

Colony #2483-4 Rear Axle Nut Spacer Washer Kit 2006-2007 Harley-Davidson Sportster - Chrome Plated
$43.45

Colony #2391-7 Front Axle Nut Spacer Wahser Kit 2007-Up Harley-Davidson FXST/FXSTB - Chrome Plated
$43.45

#2514-5 Chrome Front Axle Nut Washer Spacers Harley Dyna 08-up — Colony #2514-5 Front Axle Nut Washer Spacers 2008-Up Harley-Davidson Dyna (Except FXDWG/FXDF) - Chrome Plated
$43.45

Colony #9993-5 Front Axle Nut Smooth Spacer Kit 1997-1999 Harley-Davidson FXST/FXSTC/FXSTB/FXDWG - Chrome Plated
2 reviews $43.45

Cycle Standard Throttle Cable OEM #56400-96 2002-Up Harley-Davidson Sportster XL +8 inch Extended
$43.32

Colony #9897-6 Grease Fitting Zerk Type 1936-1984 Harley-Davidson - Chrome Plated
2 reviews $14.34

Colony #3754-1 Circuit Breaker Base Retainer 1936-1964 Harley-Davidson All Models
$21.45

Colony #8006-2 Brass Intake Manifold Seals 1936-1939 Harley-Davidson Knucklehead All 1930-1948 Sidevalve (Except 45's)
$21.45

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

Colony #2601-2 Brake Caliper Bleed Screws 1983-2004 Harley-Davidson Big Twin 1983-2003 XL - Zinc Plated
6 reviews $8.47

British Standard Miller/ Vincent STOP Reproduction Tail Light
5 reviews $42.10

Lowbrow Customs Stainless Steel Solo Seat Hinge / Pivot Bracket - Harley Ironhead Sportster 1957-1978
5 reviews $42.03

Colony #2710-1 Oversized Linkert Carburetor Venturi 1-1/8 inch OEM #27363-40
$41.97

Colony #2336-1 Linkert Carburetor Venturi 1-1/8 inch OEM #27363-40
$41.97

Colony #2334-1 Linkert Carburetor Venturi 1-1/8 inch OEM #27363-30
$41.97

Colony #2332-1 Linkert Carburetor Venturi 1-1/16 inch OEM #27362-30
$41.97

Mid-USA Replacement Caliper O-Ring Kit for Mid-USA 2 and 4 Piston Calipers
$6.99

Cycle Craft #170 Main Jet - 1988-2006 Keihin CV Carburetor
1 review $5.99

Drag Specialties Semi Metallic Rear Brake Pads 1982-E87 H-D XL 84-E87 FXR 84-E87 FXST/FLST 85-86 FXWG 85 FXE/FXEF 82-83 FXR/FXRS/FXRT 83-84 FXWG 84 FXE/FXEF
$20.95

#3088-1 Foot Shifter Lever Bushing Harley Big Twins 1970-84 — Colony #3088-1 Foot Shifter Lever Bushing 1970-1984 Harley-Davidson Big Twins
1 review $20.90

Colony #2942-2 Clutch Adjusting Hole Allen Style Filler Cap 1977-1985 Harley-Davidson Sportster
3 reviews $20.90

Colony #2557-1 Clutch Adjusting Hole Cap 1971-1976 Harley-Davidson Sportster
1 review $20.90

V-Twin Manufacturing Polished Shifter Rod 1991-2005 Harley-Davidson FXD
$29.20 $41.71

Colony #9680-6 Front Fender Mounting Kit 1936-1948 Harley-Davidson Springers - Parkerized
$20.85

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x .140 Harley-Davidson #43358-00 — Colony #43358-00 Axle/Wheel Spacer 1-1/8 x 3/4 x .140
3 reviews $5.95

Colony #8151-2 Generator Screw Kit 1936-1957 Harley-Davidson Big Twin - Chrome Plated
1 review $10.37

Colony #9654-4 Oversize Transmission Case Bottom Stud Kit 1936-1983 Harley-Davidson Big Twins - Parkerized
3 reviews $20.70

Colony #3373-2 Clutch Lever Rod End 1930-1934 Harley-Davidson Singles - CAD Plated
$20.57

Colony #3493-11 Fender to Brace Rivets & Tool 1930-1979 Harley-Davidson All Models
$20.57

Colony #2980-11 Fender to Brace Rivets and Tool 1930-1979 Harley-Davidson All Models
2 reviews $20.57

Lowbrow Customs GT Grips Black 7/8 inch
26 reviews $20.45

Colony #2070-1 Oil Line Fitting Chrome 1/8 NPT Thread for 3/8 inch Hose OEM #63533-41 - Chrome Plated
6 reviews $4.54

Colony #2810-13 Instrument Panel Light Switch Kit 1937-1938 Harley-Davidson Big Twins - CAD Plated
$40.70

Colony #3678-16 Lower Motor Mount Kit 1936-1957 Harley-Davidson OHV Big Twins - Parkerized
$40.70

Colony #2888-4 Rear Axle Nut and Smooth Spacer Kit 2005-2007 Harley-Davidson VRSC - Chrome Plated
$40.70

Colony #3387-11 Cam Cover Screw Kit 1986-2003 Harley-Davdison Sportster XL Models
2 reviews $13.54

Colony #2304-2 Handlebar Plunger 1949-1953 Harley-Davidson Big Twins/45's/Hummer Models
1 review $20.31

British Standard Throttle Cable 45" 1968-72 Triumph Bonneville T120R 1973-75 T140V Made in UK OEM #60-1819
3 reviews $40.50

Cycle Standard Clutch Release Arm 1971-1978 Harley-Davidson FX 1968-1978 FL
$40.41

Colony #2142-12 Pushrod Cover Seal Kit 1979-1984 Harley-Davidson Shovelhead
4 reviews $13.40

Lowbrow Customs Caliper Shim 6-piece Stainless Steel Kit - Stainless Steel
$10.00

Custom Dynamics Boltz Lighting - Black Trim - Red LED
$40.00

Gasbox Exhaust Port Clamps 1952-1971 Harley-Davidson K and Sportster XL Models - Stainless Steel OEM #65519-52
1 review $20.00

Prism Supply Co. Mini Sphere Shift Knob
$39.99

Lowbrow Customs Rotor Sprocket Pulley Spacer 1/8" Stainless Steel for 2000-later Harley Rear Wheel
$19.99

Colony #2762-3 Starter Crank Bushings and Seal Kit 1937-1967 Harley-Davidson Big Twins
$13.31

ODI Vans/Cult V-Twin Motorcycle Grips by ODI - Green - 1 inch
3 reviews $19.95

ODI Vans/Cult V-Twin Motorcycle Grips by ODI - Classic Orange - 1 inch
5 reviews $19.95

ODI Vans/Cult V-Twin Motorcycle Grips by ODI - Brown - 1 inch
12 reviews $19.95

Colony #9653-4 Transmission Case Bottom Stud Kit 1936-1983 Harley-Davidson Big Twins - Parkerized
4 reviews $19.93

Colony #8113-20 Transmission Side & Clutch Arm Nut Kit Harley-Davidson Big Twin 4 Speeds To 1984 - CAD Plated
2 reviews $9.96

Amal Carburetor Main Jet 240 for Concentric or Monobloc Carbs
2 reviews $13.26

Cycle Standard Throttle Cable OEM #56356-96A Harley Dyna 1996-2008 +4 inch Extended
$39.63

Colony #3374-4 Triple Clamp Bolt Kit 1932-1936 Harley-Davidson 45"/74"/80" Twins 1932-1934 C Singles - Parkerized
$39.60

Colony #3576-1 Gas Tank Rubber Divider 1936-1938 Harley-Davidson Big Twins
$19.80

Colony #9012-5 Linkert Carb Support Bracket 1939-1948 Harley-Davidson OEM #1110-39 - Parkerized
$13.20

Colony #8004-4 Intake Manifold Conversion Nipple Kit/Panhead O-ring Style Manifold 1936-1939 Harley-Davidson OHV Small Port Heads
$39.47

James Gaskets Exhaust Port Gaskets - STD Heads for Harley-Davidson Shovelheads
$13.13

Colony #9858-15 Custom Sprocket Bolt & Nut Kit 1985-Up Harley-Davidson FXWG/FXRS W/Spoke Rear Wheel - Chrome Plated
$39.11

Colony #9711-5 Shifter Lever Stud & Bushing 1936-1954 Harley-Davidson - Parkerized
3 reviews $19.51

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

Morris Magneto Replacement Magneto P6 Condenser
$19.49

Colony #2369-8 Cylinder Head Motor Brace Mounting Kit 1948-1965 Harley-Davidson Panhead - CAD Plated
6 reviews $19.48

Colony #3328-4 Exhaust Port Nuts Harley-Davidson 1986-Up XL 1984-1999 Big Twins 1999-Up Twin Cam - Zinc Plated
14 reviews $4.84

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x .645 Harley-Davidson #41594-73 — Colony #41594-73 Axle/Wheel Spacer 1-1/8 x 3/4 x .645
5 reviews $9.68

Colony #2900-1 Motor Sprocket Nut 1991-2006 Harley-Davidson Big Twins
2 reviews $19.36

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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