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 Speedometer Mounting Gasket for Harley-Davidson 1989-1991 Sportster XL Models and 1987 - 1994 FXR OEM #67104-83
30 reviews $17.93

Drag Specialties Single-Fire Ignition Coil - 1999-06 Harley-Davidson Twin Cam 2004-06 XL
2 reviews $71.64

British Standard Wheel Bearings Triumph pre unit & unit Motorcycles 1954 - 1974 OEM #37-7042
13 reviews $23.74

EMGO Triumph 19 Tooth Transmission Drive Sprocket OEM #57-1918
1 review $71.05

Cycle Standard Slotted Universal Motorcycle Horn - Chrome
12 reviews $35.51

Cycle Standard Tapered T-Bar Extensions - 1.5" High/1" Handlebars - Black
1 review $35.43

Cycle Standard Tapered T-Bar Extensions - 1.5" High/1" Handlebars - Chrome
1 review $35.43

Colony #2191-3 Brake Line Allen Banjo Bolt 3/8-24 Thread OEM #41747-82A - Chrome Plated
2 reviews $14.16

Cycle Standard Screw-In Harley Stock Style Non-Vented Gas Cap - Left Side - 1982-1995 - Black
$23.51

Drag Specialties 8.8 mm Spark Plug Wire Set - Universal
5 reviews $35.26

Colony #3568-12 Inner Primary Mount Bolts 2006-Up Harley Dyna 2007-Up Softail/Touring Models
$35.20

Colony #2808-1 Oversized Transmission and Oil Tank Drain Plug 2000-Up Harley-Davidson Big Twins - Zinc Plated
6 reviews $8.80

Colony #8408-1 Transmission Mainshaft Locknut & Washer 1936-1991 Harley-Davidson Big Twin 4 Speed
3 reviews $17.60

Red Fox Enterprises Glass License Plate Round Reflector - Burnt Orange
2 reviews $14.00

Fiorucci Fabrications Harley Big Twin Rigid Oil Tank 12V Battery Box for RTX5L-BS Battery
1 review $69.95

Gasbox Axle Plate License Plate Bracket for 1936 - 1957 Harley-Davidson Big Twin Rigid Frames
4 reviews $69.95

Gasbox Universal Motorcycle Battery Box for RTX5L-BS - Aluminum
8 reviews $69.95

Drag Specialties Primary Inspection Cover - Chrome - 1991-2003 Harley-Davidson Sportster XL
$34.95

Colony #3270-10 Rear Rotor to Hub Screw & Nut Kit 1992-Up Harley-Davidson XL/FLT/Softail/Dyna - Zinc Plated
$13.98

EMGO Amal 364 Style Single Cable Throttle Triumph Norton BSA
9 reviews $34.84

Colony #2743-2 Oversized Ignition Timer Cover Stud Kit 1980-Up Harley-Davidson Big Twin/Sportster - Zinc Plated
1 review $13.92

Colony #2487-2 Pike Nut Rear Axle Covers 1984-2007 Harley-Davidson Softail - Chrome Plated
4 reviews $69.58

Drag Specialties Turn Signal Fork Clamps - 39mm - Chrome — Cycle Standard Turn Signal Fork Clamps for 39mm Fork Tubes - Chrome
29 reviews $34.78 $47.73

Colony #3639-2 Intake Manifold Rubber Seals 1978-1984 Harley-Davidson Shovelhead & Sportster
$7.70

Cycle Standard Kickstand Spring 19366 -1987 Harley-Davidson Big Twins / Pre 1984 Ironhead Sportster Models - Black - OEM #50011-30TA
7 reviews $9.90

FNA Custom Cycle Spark Plug Wire Kits - Pink/Purple Explosion
1 review $69.00

FNA Custom Cycle Spark Plug Wire Kits - Ice Explosion
$69.00

Colony #3239-4 Front Brake Cable Handlebar Clip 1928 - 1948 Harley-Davidson Big Twins and 1932 - 1957 45's and Servi-cars — Colony #3239-4 Front Brake Cable Handlebar Clip 1928-1948 Harley-Davidson Big Twins 1932-1957 45s/Servi-cars - Chrome Plated
$23.00

British Standard Stainless Steel Top Motor Mounts / Head Steadies for unit Triumph Motorcycles
14 reviews $34.49

Colony #2048-4 Footpeg Mounting Low Head Allen Bolt/Nut Kit 1969-Up Harley-Davidson FL/FX/XL - Chrome Plated
2 reviews $17.22

Drag Specialties Swing Arm Bearing Kit 1984-99 Harley-Davidson FXST/FLST
$68.75

Lowbrow Customs Axle Spacer Kit: Lowbrow 39mm Narrow Trees / OEM 39mm Lowers / Narrow Spool Wheel
$22.87

Colony #7401-2 Tach Drive Block Off Plug 1971-1984 Harley-Davidson Sportster - Chrome Plated
7 reviews $17.14

Bare Knuckle Performance SS2 Solo Seat Springs - Barrel Style - 4 inch Stainless Steel
$34.00

Prism Supply Co. Speedometer Cable Eliminator for 1936-1984 Harley-Davidson Big Twin 4 Speed
$16.99

Colony #3269-5 Rear Disk Brake Rotor Screw Kit 1997-Up Harley-Davidson All Models - Zinc Plated
2 reviews $11.32

Colony #3240-4 Front Fender Lamp Gasket and Screw Set 1935 - 1948 Harley-Davidson Springers — Colony #3240-4 Front Fender Lamp Gasket & Screw Set 1935-1948 Harley-Davidson Springers
$16.94

Lowbrow Customs Finish Line Shifter Peg for Harleys - Black Aluminum
5 reviews $33.86

Cycle Standard Transmission Sprocket Spacer OEM# 33344-94
1 review $8.44

Colony #8807-17 Motor Mounting Kit Upper & Lower 1970-1984 Harley-Davidson Big Twin - Zinc Plated
2 reviews $33.67

Cycle Standard S&S Super E/G Carburetor Adapter for CV Air Cleaners - Chrome
2 reviews $33.53

Lowbrow Customs Radius Breather Bolt Replacement Mesh Screens and Clips
4 reviews $16.76

Goodridge 30324TC-CL Universal Braided Stainless Brake Line - 24" - Clear Coated
2 reviews $66.95

Cycle Standard Sintered Metal Disc Brake Pads for Harley-Davidson Sportster Models - 2004 & Up Rear OEM #41300053
$33.46

Lowbrow Customs Triumph Oil Feed Brass Rocker Box Acorn Nuts and Copper Washers
18 reviews $33.42

Drag Specialties 58" Shovelhead Clutch Cable for 1968-1986 Harley Big Twin 4-Speed - Replaces OEM #38618-68C
8 reviews $66.73

British Standard Kick Start Kicker Rubber for Triumph Motorcycles TR6 T120 OEM #57-2330
17 reviews $13.30

Colony #8762-17-P Primary Cover Smooth Allen Screw Kit 1971-Up Shovelhead/Evo 4 Speed - Chrome Plated
$33.17

Colony #2121-2 Rear Axle Covers 1981-2007 Harley-Davidson Softail - Chrome Plated
$66.32

Amal Carburetor Amal Carburetor Main Jets - 180
2 reviews $13.26

Cycle Standard Throttle Cable OEM #56324-81C Harley Sportster XL 1981-1985 - Blacked Out
$16.53 $23.62

Cycle Standard Screw-in Style Gas Cap Gasket replaces Harley-Davidson OEM #61109-85
24 reviews $4.13

Colony #3686-12 Lower Motor Mount Kit 1966-1969 Harley-Davidson OHV Big Twins - CAD Plated
$33.00

Colony #3735-4 Linkert Carburetor Gasket Kit 1933-65 Harley-Davidson
1 review $13.20

Colony #2595-13 Top Motor Mount Hardware 1952-1972 Harley-Davidson Big Twin 1957-1972 Sportster - CAD Plated
3 reviews $22.00

Colony #8740-19 Oil Pump Mounting Kit 1936-1967 Harley-Davidson OHV Big Twins - Chrome Plated
$33.00

Standard Motorcycle Products Ignition Sensor Assembly - 1995-97 Harley-Davidson XL 1998-03 XL1200S
2 reviews $65.95

Cycle Standard Headlight Visor - 5-3/4" Headlight - Black - Replaces OEM #69738-05
$32.97 $43.96

Colony #3034-16 Lower Motor Mount Kit Harley-Davidson All 45's 1930-1936 VL - Parkerized
1 review $32.95

Cycle Craft #40 Pilot Jet - 1988-2006 Keihin CV Carburetor
1 review $5.99

American Prime Mfg. 9/16 inch Master Cylinder Rebuild Kit For All American Prime Mfg Master Cylinders
$32.94

Goodridge Universal Braided Stainless Brake Line - 16" - Clear Coated
$21.95

Colony #3370-20 Sprocket Cover Stud Kit 1928-1934 Harley-Davidson Singles/45 Twins - CAD Plated
$32.84

Colony #9942-16-P Lifter Base Smooth Allen Mounting Kit 1999-Up Harley-Davidson Twin Cam 88 Dyna/FLT 2000-Up Twin Cam 88B Softail - Chrome Plated
1 review $16.38

Colony #9869-24 Inner Primary Mounting Kit 1980-1985 Harley-Davidson FL/FX
$32.50

Colony #2327-23 Coil Mounting Kit 1929-1947 Harley-Davidson 45s 1929-1947 VL
2 reviews $64.97

Colony #7823-12 Pushrod Covers 1948-Early 1979 Harley-Davidson Panhead & Shovelhead - Chrome Plated
4 reviews $64.80

Colony #7604-7 Upper Motor Mount Kit Acorns Nut 1936-1984 Harley-Davidson OHV Big Twins - Chrome Plated
4 reviews $21.52

Cycle Standard Tie Link - Chrome - 2004-Up Harley-Davidson Sportsters
3 reviews $64.48

Cycle Standard Gas Tank Mounting Kit 1958-1985 Harley-Davidson Sportster XL
1 review $21.49

Cycle Standard Throttle Tube - 1 inch - Single Cable - Black
30 reviews $12.85

Colony #3474-8 Gas Tank Mount Kit 1952-1978 Harley-Davidson K/KH Sportster - Parkerized
$16.04

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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Custom Motorcycle Parts FAQ

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