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

Colony #7608-6 Rear Rocker Stud Assembly 1930-1948 Harley-Davidson Big Twin Springers
1 review $53.96

Colony #7607-7 Front Rocker Stud Assembly 1930-1948 Harley-Davidson Big Twin Springers
$53.96

Goodridge P599-03-04C 90 Degree 7/16 inch Banjo Fitting - Stainless Steel
$17.95

Colony #9667-8 Oil Tank Mounting Kit - 1936-1957 Harley-Davidson Kuncklehead/Panhead - Parkerized
$13.40

Lowbrow Customs Solo Seat Hairpin Spring Mounting Kit - Stainless Washers
11 reviews $53.41

Colony #3425-10 Disc Brake Rotor Bolt Kit 1973-1980 Harley-Davidson FL Rear 1973-1974 FL Front 1973 FX/XL Front - Zinc Plated
2 reviews $13.31

Cycle Standard Headlight Visor - 7" Headlight - Chrome - Replaces OEM #69733-05
$26.55 $35.40

British Standard Outer Gearbox Gasket for unit 650cc and 750cc Triumph Motorcycles 1963- Up OEM #71-1448
13 reviews $10.62

Amal Carburetor Main Jet 230 for Concentric or Monobloc Carbs
4 reviews $13.26

Drag Specialties Universal 13 inch Battery Cable
$26.45

Colony #8449-22 Rocker Box and Rocker Shaft Cap Nut Kit 1966-1983 Harley-Davidson Shovelhead - Chrome Plated
2 reviews $52.87

Lowbrow Customs Primary Mount 13/16 inch Ignition Key Switch Bracket For Harley-Davidson Sportster 2004-2022
$26.41

Lowbrow Customs Turn Signal Bar Universal License Plate Mount
17 reviews $26.41

Colony #3043-18 Jiffy Stand and Foot Clutch Lever 1936-1978 Harley-Davidson Big Twins - Parkerized
$26.40

Colony #9619-18 Jiffy Stand & Foot Clutch Lever Bracket Mounting Kit 1936-1978 Harley-Davidson Big Twin - Parkerized
2 reviews $26.40

Colony #8763-20 Primary Cover Allen Head Screw Kit 1980-1984 Harley-Davidson Shovelhead/Evo 5 Speed - Chrome Plated
1 review $26.40

Kustom Tech Rebuild Kit for 14mm Kustom Tech Brake or Clutch Master Cylinder
2 reviews $52.61

Colony #8765-2 Point Cover Allen Head Screws 1979-Up All Harley-Davidson - Chrome Plated
3 reviews $4.38

Gasbox Front Exhaust Clamp 1958-1985 Harley-Davidson Sportster XL Models - Chrome OEM #65514-58
4 reviews $17.50

Colony #8165-19 Upper And Lower Motor Mount Kit 1936-1969 Harley-Davidson Big Twin OHV - CAD Plated
3 reviews $52.45

Cometic Gasket Inc. Cam Change Gasket Kit - 1970-92 Harley-Davidson Big Twin
$26.20

Amal Carburetor Double Banjo 150 degree Fitting for 626 928 930 932 Concentric Carbs
9 reviews $26.17

British Standard Triumph Gas Tank Mounting Kit 650cc 68-70 500cc 68-74
21 reviews $52.22

British Standard Triumph Layshaft Needle Bearing - Open Triumph Motorcycle OEM #57-1614
5 reviews $26.09

Colony #3045-14 Inner Primary Chain Guard Kit 1936-1954 Harley-Davidson Big Twins - Parkerized
1 review $26.08

Colony #3170-12 Rubber Pushrod Cover Seals 1936-79 Harley Davidson Panhead Shovelhead — Colony #3170-12 Rubber Pushrod Cover Seals 1936-1979 Harley-Davidson Panhead/Shovelhead
2 reviews $7.45

Gasbox Wideglide Headlight Mount 1948 - 1985 Harley-Davidson FLH - Tumbled Stainless
8 reviews $25.95

EK Chains 530 ZVX3 Replacement Rivet Style Master Link - Black
$12.97 $13.95

Colony #3744-1 Stem Crown Nut Kit 1936-1948 Harley-Davidson Big Twin Springer
$51.70

Colony #3014-34 Stock Fastener Motor Case Kit 1948-1964 Harley-Davidson Panhead - Parkerized
2 reviews $51.70

Colony #8135-34 Motor Case Kit Stock 1948-1964 Harley-Davidson Panhead - CAD Plated
2 reviews $51.70

Colony #2119-2 Smooth Motor Mount Bolt Covers 2000-Up Harley-Davidson Softail - Chrome Plated
6 reviews $25.72

Colony #7004-1 Acorn Stem Nut High Crown 7/8-24 - Harley-Davidson Sportster Stem - Chrome Plated
3 reviews $17.14

Lowbrow Customs Flying Monkey Grips - Black and White Stripes - 7/8 inch
30 reviews $25.65

Cycle Standard Fork Neck Cup Dust Shield Set for Harley-Davidson Big Twins OEM #43865-48A
17 reviews $10.24

Colony #2288-1 Sprocket Shaft Nut 1972-1985 Harley-Davidson Big Twins - Parkerized
1 review $17.05

Colony #8754-2 Generator Allen Screw Kit 1958-1969 Harley-Davidson Panhead/Shovelhead - Chrome Plated
1 review $12.74

Goodridge 20 Degree Side Bend 3/8 inch/10mm Banjo Fitting - Stainless Steel
2 reviews $16.95

Colony 8749-12 Transmission Top Cover Allen Screw Kit 1965-1978 Harley-Davidson Big Twin - CAD Plated
1 review $25.41

Colony #2638-8 Rear Master Cylinder Mounting Kit 1987-1999 Harley-Davidson Softail - Zinc Plated
9 reviews $16.94

No School Choppers 1928 - 1932 Ford Duolamp Tail Light Replacement Glass Lens - STOP
13 reviews $25.40

Colony #2981-2 2 inch Heavy Duty Solo Seat Springs - Made in USA - Chrome Plated
16 reviews $16.93

Colony #7141-18 Front Motor Mount Kit with Heat Treated Studs - 1957-85 Harley-Davidson Sportster - Chrome Plated
1 review $50.69

Colony #9793-9 Upper Motor Mount Kit Allen 1986-2003 Harley-Davidson Sportster - Chrome Plated
1 review $12.67

Colony #2700-1 Linkert High Speed Needle 1950-65 Harley Davidson FL — Colony #2700-1 Linkert High Speed Needle 1950-1965 Harley-Davidson FL - CAD Plated
1 review $25.30

Colony #2695-5 Linkert Low Speed Needle Valve 3-1/2 inch 1948-1965 Harley-Davidson Type 1 Heads
$25.30

Colony #2622-5 Axle Extension Nut Kit 1930-1967 Harley-Davidson Sidecars - Parkerized
1 review $25.30

Kibblewhite Precision Machining Clutch Pushrod for 650 / 750 cc Triumph Motorcycles OEM #57-1736
8 reviews $25.30

Colony #2466-5 Oversized Brake Drum Wheel Mounting Bolt Set - 1936-1972 Harley-Davidson Knucklehead/Panhead/Shovelhead - Parkerized
2 reviews $25.30

Cycle Standard Throttle Cable OEM #56356-92 Harley Dyna 1992-1995 +4 inch Extended
$25.28

Mooneyes Dice License Plate Bolts - Black
5 reviews $12.60

Cycle Standard Clutch Cable OEM #38666-00 Harley Dyna 2000-2005 - Blacked Out
$50.38 $71.97

Lowbrow Customs Steering Stem 1/8" Thick Spacing Washer - Stainless Steel
$6.28

Colony #8872-1 Fork Tube Cap/Bolt 1960-1977 Harley-Davidson OEM #45754-60 - Zinc Plated
$16.73

#2399-2 Stem Nut Stock Zinc OEM 45718-71 Harley FX FXR 71-87 XL 78-87 — Colony #2399-2 Stem Nut Stock 1971-1987 Harley-Davidson FX/FXR 1978-1987 XL - Zinc Plated
5 reviews $16.70

Colony #9970-20 Upper Pushrod Cover Kit Harley-Davidson Twin Cam 1999-Up - Chrome Plated
$50.08

Colony #3027-20 Upper Pushrod Covers Kit 1940-1947 Harley-Davidson Knucklehead - Parkerized
$50.08

Colony #8602-20 Oversize Stroker Upper Pushrod Cover Kit 1940-1947 Harley-Davidson Knucklehead & All Shovelhead - Chrome Plated
1 review $50.08

Colony #7507-20 Upper Pushrod Cover Kit 1957-1985 Sportster 1948-1965 Panhead - Chrome Plated
3 reviews $50.08

Colony #9724-30 Primary Cover Screw Kit 1936-1964 Harley-Davidson Big Twin - Parkerized
2 reviews $25.00

Colony #8923-8 Handlebar Throttle Spark Roller & Pin Kit 1910-1948 Harley-Davidson All Models
1 review $25.00

Colony #3633-2 Footpeg Rubbers 1952-1990 Harley-Davidson K/KH/XL 1971-1991 FX
$24.99

Colony #7703-2 Rear Chain Adjuster - 1952-1978 Harley-Davidson Sportster - Chrome Plated
3 reviews $24.98

Til Death Cycles TDC Wheel Hub Cover - Raw Cutout
$49.95

Gasbox 1986 - 2003 Sportster Frisco Style Gas Tank Lift Kit
20 reviews $49.95

Cycle Standard Braided Stainless Cut-To-Length Compression Brake Line - 6' - Black
$49.89

Colony #2682-17 Rear Crash Bar Mounting Kit 1938-1952 Harley-Davidson 45 Solo Models - Parkerized
$49.50

Colony #2880-3 Carburetor Float Valve and Seat 1933-1965 Harley-Davidson Linkert Carburetors
$24.75

Colony #2665-18 Rear Fender Support Mounting Kit 1959-1981 Harley-Davidson XL - CAD Plated
2 reviews $24.75

Colony #2491-1 Battery Light Wire Clip 1930-1948 Harley-Davidson Big Twin - Parkerized
$16.50

Morris Magneto Replacement Bakelite Magneto Cap - Black
$49.39

Colony #9928-20-P Motor Mounting Smooth Allen Kit 1988-2006 Harley-Davidson FLT/FLHT/FXR/FXRS - Chrome Plated
$49.25

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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