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 Black 6V Square Coil 1948-60 Harley-Davidson Big Twins
$80.82

Lowbrow Customs Banded Screw-In Gas Cap for Harley-Davidson 1996 & later - Aluminum
10 reviews $53.41

Haifley Seats Bates Style Pillion P-Pad - Tuck-n-Roll - Black & White
$160.00

Gasbox Front Pipe Exhaust Clamp 2 Piece Set 1937-1969 Harley-Davidson EL FL - Parkerized OEM #65512-37
3 reviews $20.00

British Standard 1/4 inch BSP Petcock Fuel Valve Petcock Fuel Valve - Main - UK Made For Triumph BSA Norton
8 reviews $53.33

Cycle Standard 5-3/4 inch diameter Chrome Bottom Mount Halogen Headlight
$79.99

Solid Custom Rippled Screw-In Billet Gas Cap for 1996 & later Harley-Davidson - Vented - Black
2 reviews $79.99 $99.99

Prism Supply Co. Kickstand Mounting Bracket for Harley-Davidson Big Twin Frames - Stainless Steel
$39.99

Cycle Electric Rectifying Regulator CE-206 - 1991 Harley-Davidson XL Models
$159.82 $171.09

Cycle Standard Magneto or Coil Rubber Boots - Set of 6 - For 7mm or 8mm Plug Wire
9 reviews $14.52

Lowbrow Customs Springer Riser Studs 1/2-13 x 1/2 inch-20 thread for Harley, Mid-USA, DNA, Paugcho Springers
83 reviews $15.97

Biltwell Thruster TPV Grips- Black - 1 inch
11 reviews $19.95

ODI Vans/Cult V-Twin Motorcycle Grips by ODI - Gum - 1 inch
36 reviews $19.95

Colony #2051-10 Rear Sprocket Hex Bolt/Washer Hex Kit 2000-Up Harley-Davidson Softail 2000- 2005 Dyna - Chrome Plated
2 reviews $31.87

Colony #1022 Complete Show Bike Kit Allen Knurled Hardware 2004-Up Harley-Davidson Sportster - Chrome Plated
$159.18

Drag Specialties Ape Hanger/Narrow TBW Handlebars - 1 inch - 16 inch Rise - Chrome
$158.99

Cycle Standard Fuel Inlet Fitting 1976-2006 Keihin Carburetors OEM# 2737176A
$9.89

Cycle Standard Clutch Cable OEM #38621-86A Harley 1100 1200 Sportster XL 1986-2003 +4 inch Extended
11 reviews $39.46

The Speed Merchant Speedpegs Foot Pegs - Black
$157.46 $174.95

Colony #2313-19 Upper and Lower Motor Mount Bolt Kit 1936-1969 Harley-Davidson Big Twin - Parkerized
2 reviews $52.45

PanAm Oils Inc. Oil Pressure Gauge 0-60 psi - Chrome
10 reviews $39.18

Cycle Standard Sintered Metal Front Disc Brake Pads for 1984-1999 Harley-Davidson Sportster Models OEM #44063-83
2 reviews $52.20

Goodridge Universal Braided Stainless Brake Line - 28" - Ebony
$38.95

Reverb Inc. Reverb Bullseye Tail Light
1 review $155.70

Colony #9421-21 Transmission Mounting Kit Late 1977-1986 Harley-Davidson Big Twin - Zinc Plated
$31.14

EMGO BSA A50 / A65 Shrouded Shock Absorbers
7 reviews $155.41

Prism Supply Co. 3/4"-18 Petcock Fits Early Style Harley-Davidson Tanks - Stainless Steel
$155.00

Colony #2140-40 Early Style Pushrod Cover Adaptor Kit 1990-2003 Harley-Davidson Sportster - Chrome Plated
1 review $155.00

Bates 1/4" NPT Petcock Conversion Kit 1940-65 H-D Big Twins and 45”/750 cc Sidevalves - CAD Plated
5 reviews $77.49

Reverb Inc. Reverb 69 Tail Light
$154.96

Colony #7137-22 High Crown Acorn Rocker Box Bolt Kit - 1966-1984 Harley-Davidson Shovelhead - Chrome Plated
4 reviews $51.43

Colony #3254-6 Exhaust Pipe Locking Bolt Mounting Kit 1966-1984 Harley-Davidson Shovelheads - Zinc Plated
14 reviews $22.00

Drag Specialties Ape Hanger/Narrow TBW Handlebars - 1 inch - 14 inch Rise - Chrome
3 reviews $153.69

Colony #8221-20 Head Bolt Kit 1948-Up Harley-Davidson Panhead/Shovelhead - Chrome Plated
8 reviews $76.76

The Speed Merchant 39 mm Fork Preload Adjuster - Gold Finish
$152.96 $169.95

Colony #9629-2 Rear Chain Adjusters - 1936-1972 Harley-Davidsons Knucklehead/Panhead/Shovelhead - Parkerized
4 reviews $15.29

Lowbrow Customs GT Grips Black 1 inch
30 reviews $25.40

Cycle Standard Throttle Idle Cable OEM #56355-96A Harley Dyna 1996-2008 - Blacked Out
2 reviews $25.35 $36.21

Colony #2053-10 Custom Sprocket Hex Bolt/Washer Kit Cast Rear Wheels 1997-1998 Harley-Davidson Big Twins 1997-1998 Dyna/FLT 1991-1999 XL - Chrome Plated
3 reviews $30.42

Cycle Standard Black Universal 3-piece Mounting Clamp 1 inch
9 reviews $16.90

Lowbrow Customs Lowbrow Customs Spark Plug Wire Set 1982-1994 Harley FXR and Gasbox Ironhead & Big Twin Top Motor Mounts
$25.29

Cycle Standard Exhaust Port Gasket 1984-2024 Harley-Davidson Big Twins 1986-2022 XL OEM# 65324-83 - 5 Pack
$30.25

Cycle Standard Replacement Lower 39mm Damper Springs 1987-Up Harley-Davidson XL 1991-2005 FXD 1987-1994 FXR OEM# 45374-87
$18.89

Cycle Standard Mini Speeder Bullet Style Turn Signals - Black
6 reviews $75.49

Cycle Standard Replacement Chain Conversion Sprocket - Chrome - 53 Tooth - Harley-Davidson Sportster 2000-Up Dyna 2006-Up
$75.48

Cycle Standard Clutch Cable for 2006-2016 Harley Dyna Replaces OEM #38789-06C +4" Extended
$75.40

Cycle Standard 5-3/4 inch diameter Black Bottom Mount Halogen Headlight
30 reviews $75.33

Cycle Standard Replacement Chain Conversion Sprocket - Black - 53 Tooth - Harley-Davidson Sportster 2000-Up Dyna 2006-Up
$75.22

Colony #7508-20 Upper Pushrod Cover Kit 1940-1947 Harley-Davidson Knucklehead Shovelhead and Evo - Chrome Plated
3 reviews $50.08

Lowbrow Customs 7mm Cloth 90 Degree Spark Plug Wire Sets - Black w/ Orange Tracers
9 reviews $30.02

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

Cycle Standard Replacement Dished Sprocket - Chrome - 48 Tooth - 1973-1985 Harley-Davidson Big Twin 1979-81 XL OEM #41470-73
2 reviews $75.02

Cycle Standard Replacement Dished Sprocket - Chrome - 51 Tooth - 1973-84 Harley-Davidson Big Twin 1979-81 XL OEM #41470-73
1 review $75.02

Forever The Chaos Life FTCL - Weld-on SHoRTi Passenger Foot Rests: 1.25” Coped Version
1 review $50.00

Colony #9637-13 Transmission Kicker Cover Stud Kit 1936-1984 Harley-Davidson Big Twin - Parkerized
3 reviews $25.00

Gasbox Peg Mount License Plate Bracket - 1984-2017 Harley-Davidson Softail - Vertical or Horizontal
9 reviews $49.95

Gasbox Primary Mount License Plate Bracket - 2004-Up Harley-Davidson Sportsters - Vertical or Horizontal
2 reviews $49.95

Lowbrow Customs Solo Seat Weld-On Threaded Spring Mounts
32 reviews $37.44

Fiorucci Fabrications Weld-on Universal Exhaust Mounting Slides
2 reviews $24.95

Goodridge Universal Braided Stainless Brake Line - 9" - Ebony
$24.95

Cycle Standard Replacement Chain Conversion Sprocket - Black - 48 Tooth - Harley-Davidson Sportster 2000-Up Dyna 2006-Up
$74.78

Cycle Standard Replacement Flat Sprocket - Black - 48 Tooth - 1982-1992 Harley-Davidson Sportster OEM #41470-86T
$74.78

Cycle Standard Replacement Flat Sprocket - Black - 51 Tooth - 1982-1992 Harley-Davidson Sportster OEM #41464-86
1 review $74.78

Goodridge P816-03C 1/8 inch NPT to AN3 Fitting - Stainless Steel
1 review $14.95

Goodridge 7/16-24 inch Single Banjo Bolt - Stainless Steel
$14.95

Mid-USA Replacement Pads for Four Piston Brake Calipers
$16.60

Colony #2314-36 Transmission Mounting Kit 1936-1964 Harley-Davidson Big Twin - Parkerized
3 reviews $49.41

Goodridge Universal Braided Stainless Brake Line - 32" - Ebony
6 reviews $36.95

Lowbrow Customs Solo Seat Springs - Barrel Style - 3 inch Black
26 reviews $24.60

Cycle Standard Rocker Box Covers - Chrome - 1948-65 Harley-Davidson Panhead
2 reviews $147.41

Cycle Standard Throttle Cable OEM #56308-88 Harley Sportster XL 1988-1995 - Blacked Out
4 reviews $18.40 $26.29

Cycle Standard Handlebar Clamp - Smooth - Chrome
1 review $24.48

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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