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

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x 1.520 Harley-Davidson #40981-00 — Colony #40981-00 Axle/Wheel Spacer 1-1/8 x 3/4 x 1.520
$11.53

Colony #8931-16-P Rocker Cover Smooth Allen Kit 1985-Up Harley-Davidson FL/FX 1986-Up XL - Chrome Plated
$23.01

Colony #2280-16 Rocker Cover 12 Point Screw Kit 1985-Up Harley-Davidson FL/FX 1986-Up XL - Chrome Plated
$23.01

Colony #3763-5 Generator Strap Rebuild Kit 1930-1957 Harley-Davidson 45's/VL/Knucklehead/Panhead
$23.00

Colony #3135-3 Jiffy Stand Mounting Kit Zinc Harley Sportster XL 1989-97 — Colony #3135-3 Jiffy Stand Mounting Kit 1989-1997 Harley-Davidson Sportster XL - Zinc Plated
1 review $11.50

Colony #8812-16 Rear Brake Drum Bolt Kit 1966-1978 Harley-Davidson Sportster - CAD Plated
4 reviews $23.00

Colony #2801-16 Brake Rear Drum Bolt Kit 1952-1965 Harley-Davidson K/KH/XL - CAD Plated
$23.00

Lowbrow Customs Lowbrow Customs Spark Plug Wire Set 2004-2006 Harley-Davidson XL 1999-2008 FLH/FLT
$22.99

Colony #8604-16 Lifter Base Screw Kit Hex Head 1954-1974 Harley-Davidson Big Twin - Chrome Plated
3 reviews $22.78

Colony #2463-8 Gas Tank Clip Mounting Kit 1925-1936 Harley-Davidson JD/DL/RL/VL/Singles - CAD Plated
1 review $22.77

Colony #9100-8 Cylinder Base Nut Set 1978-1984 Harley-Davidson Shovelhead OEM #16838-78 - Chrome Plated
2 reviews $22.75

Colony #2953-5 Carburetor Support Bracket 1954-E1955 Harley-Davidson OHV Big Twins - Parkerized
$22.50

Colony #3751-1 Intake Manifold Conversion Nipple 1940-Up Manifold On 1936-1939 Harley-Davidson OHV
$22.45

Colony #3140-4 Oversize 1/2-13 Transmission Case Bottom Stud Kit 1915-1936 Harley-Davidson Twins
$22.45

Colony #2995-1 Oversized Cylinder Head to Manifold Nipple 1940-1954 Harley-Davidson 74s 1953-1956 K/KH
$22.45

Colony #9655-4 Extra Oversize Transmission Case Bottom Stud Kit 1936-1983 Harley-Davidson Big Twins - Parkerized
$22.45

Mooneyes Glitter Dice Air Valve Caps - Blue
$11.20

Mooneyes Dice Air Valve Caps - Red
3 reviews $11.20

Lowbrow Customs 3/4 inch ID x 1/2 inch Long Aluminum Motorcycle Wheel Axle Spacers - Pair
12 reviews $11.18

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x 1.406 Harley-Davidson #43674-95 — Colony #43674-95 Axle/Wheel Spacer 1-1/8 x 3/4 x 1.406
$11.17

Colony #8788-11-P Primary Cover Smooth Allen Screw Kit 1977-1985 Harley-Davidson Sportster - Chrome Plated
$22.34

Colony #9767-15 Primary Cover Allen Screw Kit 1991-1993 Harley-Davidson XL - Chrome Plated
1 review $22.34

Colony #8762-17 Primary Cover Allen Head Screw Kit 1971-Up Harley-Davidson Shovelhead/Evo 4 Speed - Chrome Plated
2 reviews $22.34

Colony #8787-2-P Generator Smooth Allen Screw Kit 1971-1985 Harley-Davidson Sportster - Chrome Plated
1 review $11.14

Colony #2468-8-P Transmission to Motor Mount Smooth Allen Bolt Kit 2007-Up Harley-Davidson Softail/Dyna/FLT - Chrome Plated
$11.14

Colony #8849-2 Circuit Breaker Post Rebuild Kit 1948-1969 Harley-Davidson FL/XL/K/45's
$11.14

Colony #3381-1 Lower Head Cone 1930-1938 Harley-Davidson 1930-1934 C Singles - CAD Plated
$22.00

Colony #3716-2 Battery Mat Set 1915-1964 Harley-Davidson 6 Volt Battery Models
1 review $11.00

Colony #3592-10 Front Disc Rotor Torx Screws 2014-Up Harley-Davidson Touring Models - Zinc Plated
$22.00

Colony #3385-1 Head Cone Locknut 1930-1938 Harley-Davidson 1930-1934 C Singles - CAD Plated
$22.00

Colony #3266-5 Rear Axle Spring Clip Set 1991-Up Harley-Davidson FL/FX/XL - Zinc Plated
5 reviews $11.00

Colony #2209-4 Clutch Cable Bracket 1952-1970 Harley-Davidson K/KH/XL/XLH - Parkerized
$22.00

Colony #9669-9 Tool Box Mounting Kit 1935-1954 Harley-Davidson All Models - Parkerized
3 reviews $22.00

Colony #3363-1 Carburetor Choke Rod 1941-1947 Harley-Davidson OHV Big Twins - Parkerized
$21.99

Cycle Standard Transmission Neutral Switch 1999-Up Harley-Davidson Sportster
2 reviews $21.95

Morris Magneto Replacement Magneto Cap AFM Cometic Gasket Harley-Davidson OEM# 29550-55
$10.91

Colony #3459-6 Primary Chain Adjuster Mounting Kit 1979-1985 Harley-Davidson Sportster - Zinc Plated
2 reviews $21.78

Colony #3384-4 Gas Tank Spacers 1952-1981 Harley-Davidson K/XL- 4 pack - CAD Plated
1 review $10.89

Colony #9018-5 Hand Shifter Lever Stud and Bushing Kit 1936-1954 Harley-Davidsons - Chrome Plated
$21.73

Colony #8008-1 Acorn Stem Nut Fits Harley-Davidson 45 Springers - Chrome Plated
1 review $21.73

Colony #7618-1 Custom Stem Bolt 1957-1978 Harley-Davidson Sportster - Chrome Plated
$21.73

Colony #7017-16 High Crown Acorn Cylinder Base Nut Set - 1930-1977 Harley-Davidson 74's - Chrome Plated
$21.66

Colony #9751-11-P Cam Cover Smooth Allen Screw Kit 1986-Up Harley-Davidson Sportster - Chrome Plated
$21.66

Colony #2344-10-P Oil Pan Mounting Kit Smooth Allen 2006-Up Harley-Davidson Dyna - Chrome Plated
$21.60

Colony #8820-9 Transmission Side Cover Allen Screw Kit 1936-Up Harley-Davidson Big Twin 4 Speeds - Chrome Plated
$21.60

Colony #2528-10-P Gas Tank Mounting Smooth Allen Kit 1990-1995 Harley-Davidson Softail - Chrome Plated
$21.51

Colony #9621-12 Timing Cover Screw Kit 1936-1969 Harley-Davidson Big Twins
3 reviews $21.30

Colony #8150-12 Timing Cover Screw Kit 1936-1969 Harley-Davidson Big Twins - CAD Plated
$21.30

British Standard Brake Arm Pivot Pin - Triumph 500 650 750
5 reviews $21.29

Gasbox Replacement Hardware for Lowbrow Customs Straight Leg Bolt-On Hardtail Rear Frame Section for 1967-1978 H-D Ironhead Sportster
$21.25

Colony #2172-16 Alternator Cover/Derby Cover Allen Screw Kit 2002-Up Harley-Davidson VRSC - Chrome Plated
1 review $21.22

Colony #3077-18 Exhaust System Parkerized Mounting Bolt Kit Harley 45s 32-73
$21.12

Colony #8104-16 Cylinder Base Nuts 1930-1978 Harley-Davidson Big Twins - Chrome Plated
$20.99

Goodridge Universal Braided Stainless Brake Line - 14" - Clear Coated
$20.95

Colony #2944-2 Clutch Adjusting Hole Filler Cap Allen Style 1985-1990 Harley-Davidson XLH
$20.90

Colony #3244-1 Oil Tank Mounting Bracket 1966-1969 Harley-Davidson XLCH - Parkerized
$20.90

Colony #3314-1 Aluminum Axle Spacer Stock 5 inch x 25mm ID
2 reviews $20.90

Colony #2875-1 Rear Axle Spacer 1967-1972 Harley-Davidson FL/FLH - Chrome Plated
$20.90

Colony #41505-07 Axle/Wheel Spacer 2-7/16 x 1 x .790 Harley-Davidson OEM #41505-07 - Chrome Plated
$20.88

Colony #2496-2 Tappet Oil Screen and Spring 1966-1969 Harley-Davidson Shovelhead
1 review $6.96

Colony #9946-20-P Cam Cover Mounting Kit Smooth Allen Kit 1999-Up Harley-Davidson Twin Cam 88 Dyna/FLT 2000-Up Twin Cam 88B Softail - Chrome Plated
3 reviews $20.85

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x .990 Harley-Davidson #43683-00 — Colony #43683-00 Axle/Wheel Spacer 1-1/8 x 3/4 x .990
3 reviews $10.42

Colony Axle / Wheel Spacer 1-1/8 x 3/4 x 1.000 Harley-Davidson #43657-89 — Colony #43657-89 Axle/Wheel Spacer 1-1/8 x 3/4 x 1.000
1 review $10.42

Colony Axle / Wheel Spacer 1-1/2 x 1 x .630 Harley-Davidson #40437-01 — Colony #40437-01 Axle/Wheel Spacer 1-1/2 x 1 x .630
$10.42

Colony #9678-2 Generator Screws 1930-1948 Harley-Davidson Big Twin Sidevalve - Parkerized
$10.37

Colony #9689-4 Front Axle Nut Kit 1929-1936 Harley-Davidson 45 Solo 1926-1934 SIngles - Parkerized
$5.18

Colony #2881-8 Lower Shock Mount Bolt And Nut Kit 2002-2005 Harley-Davidson Dyna - Chrome Plated
2 reviews $20.70

Colony #9986-8 Custom Lower Shock Mount Bolt/Nut Kit 1991-2001 Harley-Davidson Dyna - Chrome Plated
$20.70

Colony #9206-12 Oil Tank Bracket to Frame Mounting Kit - 1958-1964 Harley-Davidson Panhead - CAD Plated
$20.70

Colony #9739-2 Front Brake Cable Adjusting Screw 1941-1948 Harley-Davidson Big Twin 1941-1957 45 Servicar - Chrome Plated
$20.65

Colony #3158-14 Oil Tank Mount Kit 1958-1965 Harley-Davidson XLCH/XLR 1952-1967 KR/KRTT - CAD Plated
$10.29

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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