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 Derby Cover - Chrome - 1970-1998 Harley-Davidson Big Twins
$32.74

LCFabrications Riser Adapter for Integrated Top Triple Tree
$49.00

Red Fox Enterprises Glass License Plate Round Reflector - Green
7 reviews $14.00

No School Choppers 1928 - 1932 12V LED Ford Duolamp - Original Red Lens - Model A Stainless Steel Tail Light
$97.73

Colony #8623-2 Seat Clevis Pin & Spring 1929-Up Harley-Davidson
5 reviews $13.94

EMGO Throttle for 7/8 inch Handlebars - Dual Pull - All Metal, Amal Style
10 reviews $32.52

Colony #2230-6 Intake Manifold Nipple Repair Kit 1948-1954 Harley-Davidson OHV - CAD Plated
2 reviews $24.37

Cycle Standard Clutch Friction Disc Set 1984-1990 Harley-Davidson Sportster XL
$97.44

Cycle Standard Master Cylinder Gasket Harley-Davidson OEM #45012-72
14 reviews $6.09

Colony #3194-1 Harley Primary Drain Plug - Zinc Plated - Big Twin & Softail - 1987-2003 & 1993-2003
16 reviews $9.68

Cycle Standard Throttle Cable OEM #56356-92 Harley Dyna 1992-1995
2 reviews $24.10

British Standard Triumph Oil Seal Timing Cover Points Seal OEM #70-4568
12 reviews $16.02

Saddlemen 1/4 inch -20 Seat Mount Knob - Black
6 reviews $8.00

Colony #2604-12 Footboard Mounting Kit 1930-1936 Harley-Davidson VL - Parkerized
1 review $48.00

Goodridge 20 Degree 7/16 inch Banjo Fitting - Stainless Steel
$31.95

Colony #8225-8 Rocker Shaft End Plug & Cap Kit 1971-Up Harley-Davidson Shovelhead 1971-1985 XL - CAD Plated
2 reviews $31.81

Prism Supply Co. 3/8" NPT Petcock - Brass
2 reviews $94.99

Colony #3274-2 Dome Shaped Front Axle Covers 1988-2011 Harley-Davidson Softail Springer/Heritage Springer - Chrome Plated
3 reviews $31.63

Colony #9798-20 Front Motor Mount Kit Stock 1957-1984 Harley-Davidson Sportster - Chrome Plated
2 reviews $47.38

Colony #3693-20 Rear Fender Rail Screw Kit 1972-1986 Harley-Davidson FX - Chrome Plated
1 review $23.65

EMGO Throttle Cable 42" 1968-72 Triumph Bonneville T120R 1973-75 T140V OEM #60-1819
8 reviews $23.60

Lowbrow Customs Crescent Moon Motorcycle Mirror - Perch Mount - Black
$47.07

Lowbrow Customs Crescent Moon Motorcycle Mirror - Perch Mount - Chrome
$47.07

Cycle Standard Cycle Standard 24"" Handlebar Wiring Extension Kit for 1996-2006 Harley Models
10 reviews $46.94

Colony #2192-3 Brake Line Hex Banjo Bolt 7/16-24 Thread OEM #41739-84A - Chrome Plated
1 review $15.64

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x 1.218 Harley-Davidson #41595-86 — Colony #41595-86 Axle/Wheel Spacer 1-1/8 x 3/4 x 1.218
$10.42

Drag Specialties Small Radius Laydown 3 Bolt Style License Plate Mount Assembly - Chrome
$93.61

Colony #2220-24-P Primary Cover Smooth Allen Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$46.71

Colony #2780-2 Swingarm Covers 2008-Up Harley-Davidson Softail - Chrome Plated
1 review $31.13

Til Death Cycles Lo-Pro XL Footpeg Clevis for 2004-2022 Sportster Models with Mid Controls
1 review $93.27

Cycle Standard Muffler T-Bolt Set
$23.31

Cycle Standard Single Cable Throttle - 7/8 inch - With Jackhammer Grips
17 reviews $46.60

Cycle Standard 45 Degree Elbow 1/8 inch NPT Male To Female - Chrome
$7.76

Lowbrow Customs 60 psi Oil Pressure Gauge - White Face
24 reviews $46.49

Amal Carburetor Main Jet 220 for Concentric or Monobloc Carbs
1 review $13.26

Colony #7502-2 Oversize Drain Plug & Tap Kit 1965-Up Harley-Davidson Big Twins 1967-Up Sportster - Chrome Plated
2 reviews $46.35

Cycle Standard Round Motorcycle Mirror - Clamp On - Black
9 reviews $30.82 $37.86

Cycle Standard Battery Hold Down Rod - Chrome - Early Harley-Davidson 6 Volt Big Twins
3 reviews $18.44

Colony #7410-1 Sprocket Shaft Bearing Retainer with Lip Seal Standard Size Replaces 1955-1968 Harley-Davidson 74's
7 reviews $45.98

Lowbrow Customs Chrome Rear Axle Spindle Nut - Thick - 500 650 Triumph #82-1747
13 reviews $15.31

Goodridge 30318TC-CL Universal Braided Stainless Brake Line - 18" - Clear Coated
$61.95

Cannonball Custom Transmission Adjuster Custom for Cannonball Transmission Base Plate 1936-1985 4 Speed Harley-Davidson Big Twins
$91.46

Drag Specialties Shifter Linkage - Chrome - 1986-2017 Harley-Davidson FLS/_FXST/_FXS/_FLST
$45.53

Lowbrow Customs Air Cleaner Backplate Gasket for CV Carburetor
28 reviews $2.22

Cycle Standard Throttle Cable OEM #56313-76 Harley Sportster XL 1976-1980 +4 inch Extended
12 reviews $30.32

Colony #8934-2 Rear Axle Adjuster Screws 1986-1992 Harley-Davidson FXST - Chrome Plated
1 review $18.16

Cycle Standard Fly By Wire Throttle Tube - 1 inch - Black
26 reviews $12.97

Morris Magneto Lightning Bolt Magneto Kill Lever
$15.00

Hawthorn Co. Cycles Battery Box Antigravity 12 Cell w/ Breaker Mount
$90.00

Martian Machine Heart Cast Aluminum Points Cover - Veritcal
2 reviews $45.00

Gasbox Front Pipe to Frame Clamp Set for 1958 - 1969 Harley-Davidson FL Models - Parkerized - OEM #65513-58, 65512-37A
4 reviews $22.50

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

Biltwell Macho Negro Chromoly Solo Seat Hinge / Pivot - Black
53 reviews $89.95

Drag Specialties AGM Maintenance Free Battery 2004-Up Harley-Davidson Sportster XL 15-20 XG 500/750/750A
$89.94

Cycle Craft #175 Main Jet - 1988-2006 Keihin CV Carburetor
$5.99

Gasbox Side Mount Headlight Bracket Set for Harley 39mm Narrow Glide Front Forks
5 reviews $29.95

Cycle Standard Chrome Solo Seat Spring Support Bracket Harley Ironhead Sportsters 1957-78
15 reviews $29.94

Colony #7119-2 Threaded Cylinder Head to Manifold Nipple With O-ring Seal - 1940-1954 Harley-Davidson OHV 74's 1953-56 K/KH
1 review $22.45

Colony #9859-20 Lower Motor Mount Kit 1988-2006 Harley-Davidson FLT/FLHT/FXR/FXRS - Chrome Plated
1 review $44.89

Colony #2139-4 Handlebar Riser Hex Bolt Kit 1/2-13 x 3-3/4" - Chrome Plated
$14.89

Colony #2123-4 Handlebar Riser Cupped Washers 1973-Up Harley-Davidson All Models - Chrome Plated
3 reviews $14.89

Cycle Standard 35mm Fork Seal Rebuild Kit - Showa Forks - 1984-87 Harley-Davidson XL FX FXR
6 reviews $17.85

Lowbrow Customs Moto Luggage Rack - Left Side - 2004-2022 Harley-Davidson Sportsters
$89.24 $104.99

Cycle Standard Throttle Idle Cable OEM #56309-88 Harley Sportster XL 1988-1995 +4 inch Extended
4 reviews $29.72

Lowbrow Customs Banded Screw-In Gas Cap for Harley-Davidson 1982-1995 / Modern Triumph Bonneville T100 / T120, Scrambler, Thruxton - Brass
7 reviews $89.06

Lowbrow Customs Domed Screw-In Gas Cap for Harley-Davidson 1982-1995 / Modern Triumph Bonneville T100 / T120, Scrambler, Thruxton - Brass
10 reviews $89.06

Lowbrow Customs Banded Screw-In Gas Cap for Harley-Davidson 1996 & later - Brass
38 reviews $89.06

Drag Specialties XLX Style Front Fender 1999-05 Harley-Davidson Dyna 86-Up XL 11-Up 883L/1200C/1200CX 14-20 1200T
2 reviews $88.95

Colony #9912-2 Fork Tube Cap 1978-Up Harley-Davidson FL/FXWG/Softail - Chrome Plated
$22.09

British Standard Sealing Washer for British 1/4 inch BSP Petcocks OEM #70-7351 - Triumph BSA Norton
17 reviews $8.81

Goodridge 30354TC-CL - Universal Braided Stainless Brake Line - 54" - Clear Coated
$87.95

Cycle Standard Front Fender - Harley-Davidson 1973-up XL FX FXR 35mm 39mm Narrow Glide Front Forks - OEM #59031-83
7 reviews $87.92

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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