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

Prism Supply Co. Blade Style Push-in Oil Plug - Polished
$59.99

PanheadEric Precision Extended Magneto Cap Screws
1 review $39.99

Motion Pro 1/4 inch NPT Mini Petcock Straight Outlet - No Reserve
9 reviews $19.99

Til Death Cycles TDC Wheel Hub Cover - Black Cutout
2 reviews $59.95

Gasbox 4 Speed Transmission Mounting Plate for 1937 - 1957 Harley-Davidson Big Twins OEM #47698-36
1 review $59.95

Colony #7800-8 Acorn Bolt Transmission Mounting Plate to Frame Kit 1936-1986 Harley-Davidson Big Twins & 4 Speed - Chrome Plated
5 reviews $23.91

Colony #2342-18 Primary Cover Allen Screw Kit 2006-Up Harley-Davidson Dyna - Chrome Plated
1 review $29.78

Cycle Standard Spark Plug Boots and Terminals - 90 Degree Boots - For 8mm Plug Wire — Cycle Standard Spark Plug Boots and Terminals - 90 Degree Boots - For 7mm or 8mm Plug Wire
17 reviews $11.88

Drag Specialties Aramid Fiber Clutch Plate Set 1991-2022 Harley-Davidson XL 1990-1997 Big Twin
$118.67

Colony #7344-6 Intake Manifold Conversion Nipple Kit 1940-1954 Harley-Davidson 74's
1 review $39.47

S&S Cycle Rebuild Kit Super E Carburetor Body - S&S Cycle #11-2906
1 review $58.86 $61.95

British Standard Exhaust Spigot 1963-1971 Triumph 650 Bonneville Tiger - Oversize
3 reviews $58.79

Colony #9213-4 Upper Inner Pushrod Covers 1979-Up Harley-Davidson Shovelhead 1984-Up Evo 1986-1990 XL
2 reviews $39.11

Colony #8714-20 Big Bore Headbolt & Washer Kit 1949-Up Harley-Davidson Panhead/Shovelhead - Chrome Plated
2 reviews $58.66

Cycle Standard Fork Boot Gaiter Set for 1954-1970 Harley-Davisdson Ironhead Sportster XL Models OEM #46001-54
5 reviews $38.91

Colony #3134-4 Jiffy Stand Mount Kit Harley Davidson V-rod/ST/XL — Colony #3134-4 Jiffy Stand Mount Kit Harley-Davidson 2007-2017 Harley-Davidson Softail 1998-Up Sportster 2002-Up VRSC - Zinc Plated
46 reviews $19.36

Lowbrow Customs 22mm to 1/4 inch NPT Brass Petcock Adapter Nut
18 reviews $29.00

Cycle Standard Model A Tail Light Mounting Bracket - Vertical License Plate
16 reviews $19.33

S&S Cycle Standard Band Intake Manifold - Super B/E - 1978-1984 Harley-Davidson Shovelhead
1 review $115.90 $121.95

Colony #9810-4 Smooth Rear Axle Nut & Spacer Kit 1984-1999 Harley-Davidson Softail - Chrome Plated
$57.94

Colony #3415-1 Fork Neck Cup 1930-1957 Harley-Davidson 1930-1934 C Singles - CAD Plated
$38.50

Drag Specialties Speedometer Relocation Bracket - Chrome - 2004-2013 Harley-Davidson Sportster XL (EXCEPT 883C/1200C)
2 reviews $115.49

Cycle Standard Shift Lever - 1997-2013 Harley-Davidson Big Twins - Chrome - OEM #33849-97
5 reviews $38.37

Drag Specialties LED Handlebar Marker Lights - Black - Amber Lens
2 reviews $114.43

James Gaskets Complete Motor Gasket Kit - Sportster 900cc 1957 - 1971
1 review $114.43

Cycle Standard Ignition Advance Unit - Stainless Steel - 1970-Up Harley-Davidson OEM #3251770T
1 review $57.13

James Gaskets 5 Speed Transmission End Cover Gasket 1987-2006 Harley-Davidson Big Twin
1 review $6.34

Cycle Standard Round Motorcycle Mirror - Perch Mount - Black
19 reviews $37.97

Goodridge 45 Degree Tube Adapter - Ebony
$18.95

Cycle Standard Harley-Davidson FX XL Style LED Turn Signal - Replaces OEM #68404-86
1 review $37.73

British Standard Engine Oil Seal Kit - 7 Piece - 1963 - 1972 Triumph Unit 650
21 reviews $56.39

Cycle Standard Clutch Cable OEM #38602-92 Harley Dyna 1992-2005 +4 inch Extended
2 reviews $56.37

Lowbrow Customs Smooth 1" Handlebar Springer Risers - Black
2 reviews $112.47

Lowbrow Customs Smooth 1" Handlebar Springer Risers - Aluminum
1 review $112.47

No School Choppers 1928 - 1932 Ford Duolamp - Red/Yellow Lens - Model A stainless steel Tail Light for your bobber or chopper
$56.16

No School Choppers 1933 - 1936 Ford stainless steel Tail Light for your bobber or chopper
31 reviews $56.16

British Standard Brake Cable for 1965-1967 Triumph Made in UK OEM #60-0559
1 review $55.81

James Gaskets Fork Seal Rebuild Kit 1977-1983 Harley-Davidson FL FLH FLH-80 FLT-80 FLT Classic
3 reviews $22.20

Red Fox Enterprises Prism Cut Glass Dot - Green
$13.85

Lowbrow Customs Aluminum Gas / Oil Filler Cap - Unvented
6 reviews $27.68

British Standard Side Cover Allen Hardware Set - Triumph 650 / 750 c.c. Motorcycles 1969 & up
7 reviews $27.67

Cycle Standard Shift Lever - 1986-1990 Harley-Davidson XL - Chrome - OEM #34605-86TB
$36.86

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x .732 Harley-Davidson #43654-86A — Colony #43654-86A Axle/Wheel Spacer 1-1/8 x 3/4 x .732
4 reviews $10.04

No School Choppers 1928 - 1932 12V LED Ford Duolamp - Stop Lens - Model A Stainless Steel Tail Light
1 review $110.24

No School Choppers 1928 - 1932 12V LED Black Out Ford Duolamp - Stop Lens - Model A Stainless Steel Tail Light
$110.24

Prism Supply Co. 3/8" NPT 90 Degree Petcock - Brass
$109.99

Prism Supply Co. Prism Supply Co. Ripple Tail Light - Gloss Black
$109.99

Cycle Standard Isolator Motor Mount - Rear - 1991-1998 Harley-Davidson Dyna
$109.89

Colony #3536-16 Head Bolt Set 1940-1951 Harley-Davidson WR/WLDR - CAD Plated
$109.62

Cycle Standard Z Bar Handlebars - 1 inch - 2 inch Rise - Black
1 review From $109.34

Cycle Standard Exhaust Port Gasket 1984-2024 Harley-Davidson Big Twins 1986-2022 XL OEM# 17048-98 - 2 Pack
$12.10

Cycle Standard Transmission Mounting Plate 1986-1999 Harley-Davidson Softail - Chrome
$36.27

British Standard Gas Tank Mounting Kit Triumph 1963-67 T120 TR6 T100 TR5 OEM #00-0088
11 reviews $54.38

Cycle Standard Custom Flush Mount Polished Stainless Steel Pop-Up Gas Cap and Weld In Bung
9 reviews $108.43

Cycle Standard Oil Temperature Dipstick OEM #62896-00 Harley-Davidson 2000 & Up Softail
19 reviews $36.14

Colony #2263-2 Pike Nut Front Axle Covers 1972-1999 Harley-Davidson FL 80-86 FXWG 84-06 Softail 88-94 FXR - Chrome Plated
2 reviews $54.14

Lowbrow Customs 8mm Cloth Straight Spark Plug Wire Sets - Oak with Red and Black tracers
1 review $36.03

Lowbrow Customs 8mm Cloth Straight Spark Plug Wire Sets - Black with Red tracers
3 reviews $36.03

Colony #3732-1 Upper/Lower Fork Neck Bearing Race 1936-1949 Harley-Davidson Knucklehead 1937-1948 Big Twin U Models 1948-1949 Panhead
$27.00

Prism Supply Co. Weld-On Steel Light Mount With License Plate Bracket - Prism Supply Co. PS-41 Tail Light
$26.99

Drag Specialties AGM Maintenance Free Battery 2000-Up Harley-Davidson Softails 99-17 FXD/FXDWG/FLD
3 reviews $107.94

Goodridge Universal Braided Stainless Brake Line - 23" - Ebony
2 reviews $35.95

Colony #2667-22-P Lower Motor Mount Allen Bolt Kit 1999-2003 Harley-Davidson Sportster - Chrome Plated
3 reviews $35.87

Colony #9772-22-P Lower Motor Mount Smooth Allen Kit 1986-1998 Harley-Davidson Sportster - Chrome Plated
1 review $35.87

Lowbrow Customs Finish Line Grips - Black Aluminum - 1 inch
19 reviews $107.29

Cycle Standard Universal 1.75" Exhaust Muffler Clamp Set - Chrome
$26.79

British Standard Triumph 650 Head Bolt Set 1963 - 1970 OEM #70-0327
8 reviews $106.89

Lowbrow Customs Domed Screw-In Gas Cap for Harley-Davidson 1982-1995 / Modern Triumph Bonneville T100 / T120, Scrambler, Thruxton - Aluminum
2 reviews $53.41

Autolite Spark Plug- 1966-1974 Shovelhead/ 1948-1968 Panhead - Manufacturer Part #4275
9 reviews $6.27

Colony #9307-17 Primary Cover Screw Kit 1970-1980 Harley-Davidson Shovelhead - Chrome Plated
2 reviews $21.29

EMGO Speedometer Cable for BSA A65 / Triumph - 66 inch - OEM #60-3249
9 reviews $26.61

EMGO Clutch Cable for Triumph 650cc 1968-1972 OEM #60-1993
12 reviews $26.59

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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