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.

Custom Motorcycle Parts

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BEST SELLING BRANDS

TOP Custom Motorcycle Parts

Colony #2727-1 Chain Housing Top or Shifter Lever Pivot Screw 1965-1984 Harley-Davidson FL 1971-1984 FX - CAD Plated
1 review $7.26

Colony #2684-1 Rear Wheel Brake Rod and Cable Adjusting Nut 1952-1978 Harley-Davidson K/KH/Sportster - Chrome Plated
1 review $7.26

Colony #2629-4 Speedometer Mounting Kit 1936-Up Harley-Davidson Stewart-Warner Speedometers - CAD Plated
1 review $3.63

Colony #2046-8-P Voltage Regulator Mounting Kit Smooth Allen 2000-Up Harley-Davidson Softail - Chrome Plated
1 review $7.17

Colony #9670-10 Star Wheel Hub Outer Screw Kit 1936-1966 Harley-Davidson - Parkerized
1 review $7.17

Colony #3520-9 Crankcase Relief Pipe Gasket Kit 1937-1973 Harley-Davidson 45s 1937-1948 Sidevalve Models - CAD Plated
$7.15

Colony #2270-4 Passenger Peg Allen Mounting Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
1 review $7.06

British Standard Stator Lock Tab Washer Triumph BSA Twins and Singles
6 reviews $7.00

Colony #8208-2 Generator Screw Kit 1937-1957 Harley-Davidson 45's - CAD Plated
$6.78

Colony #3090-3-P Sprocket Cover Mounting Kit Polished Allens 2007-Up Harley-Davidson VRSC - Chrome Plated
$6.70

Colony #2173-3-P Sprocket Cover Smooth Allen Mounting Kit 2002-2005 Harley-Davidson VRSC - Chrome Plated
1 review $6.70

Colony #3040-7 Rear Chainguard Mounting Kit 1936-1952 Harley-Davidson 45 Solo 1937-1973 Servi-car - Parkerized
$6.66

Colony #9746-7 Rear Chain Guard Mounting Kit 1936-1952 Harley-Davidson 45 Solo Pre-1973 Servicar - Parkerized
1 review $6.66

Colony #3646-5 Ignition Coil Mounting Plate Kit 1965-1984 Harley-Davidson FL/FX/XL - Zinc Plated
$6.60

Colony #3637-2 Oil Line Tube Seals 1992-1999 Harley-Davidson Big Twins
$6.60

Colony #3329-4 Exhaust Port Nuts 1984-1999 Harley-Davidson Big Twin 1986-Up XL 1999-Up Twin Cam - Chrome Plated
$6.49

Colony #9842-8 Rocker Shaft End Nut Kit 1936-1947 Harley-Davidson Knucklehead - Parkerized
$6.38

Colony #9950-6-P Oil Hose Cover Mounting Kit Smooth Allen 1999-Up Harley-Davidson Twin Cam 88 Dyna/FLT - Chrome Plated
$6.38

Colony #9657-8 Transmission Top Cover Screw Kit 1979-1985 Harley-Davidson Big Twin - Zinc Plated
$6.38

Colony #2267-4 Shifter Rod Linkage and Shifter Mount Allen Kit 2004-Up Harley-Davidson Sportster - Chrome Plated
$6.33

Colony #3394-10 Oil Pump Mounting Kit 1977-1990 Harley-Davidson Sportster - CAD Plated
$6.29

Cycle Standard Kickstand Bumper Rubber - 1986-2000 Harley-Davidson Sportster 1989-06 Softail OEM #62123-66
$6.15

Colony #2729-1 Carburetor Bowl Valve Cover Cap 1933-1952 Harley-Davidson 45s 1933-1948 Sidevalve Servi-carK/KH - CAD Plated
$6.05

Colony #2732-1 Carburetor Bowl Valve Cover Cap Brass 1933-1952 Harley-Davidson 45s 1933-1948 Sidevalve 1953-1954 Servi-car 1952-1956 K/KH
$6.05

Colony #8402-2 Point Cover Acorn Head Screws 1971-Up Harley-Davidson Shovelhead & Sportster - Chrome Plated
3 reviews $5.96

Colony #3579-1 Axle Spacer - 1-1/2 inch O.D. x 25MM I.D. x 1/8 inch Thick - Chrome Plated
$5.95

Colony #2324-2 Air Cleaner Cover Mounting Screws 1966-1977 Harley-Davidson Big Twin 1956-1977 XL - Chrome Plated
1 review $5.95

Colony #3388-8 Gas Tank Mounting Kit 2004-Up Harley-Davidson Sportster XL
$5.80

Gasbox Replacement Tabs for Lowbrow Customs Weld-On Hardtail Frame for 1982-2003 Harley Sportster
$1.43

Colony #3761-5 Dash Cover Mounting Kit 1936-1946 Harley-Davidson Twins - CAD Plated
$4.95

Dill Air Controls Rubber Valve Stem - Pull-in TR-412 - Chrome
1 review $4.95

Colony #3185-4 Battery Wing Nuts Parkerized 1/4-20 — Colony #3185-4 Battery Wing Nuts 1/4-20 Harley-Davidson OEM #4409-24 - Parkerized
$4.84

#3100-4 Battery Box Lid Wing Nuts Harley-Davidson 66387-26 — Colony #3100-4 Battery Box Lid Wing Nuts Harley-Davidson OEM #66387-26
1 review $4.84

Colony #2657-3 Clutch Hub Bearing Plate Springs 1944-1984 Harley-Davidson Big Twins 1944-1973 45's - CAD Plated
$4.84

Colony #8171-8 Cylinder Base Nut Lockwashers All 1930-1977 Harley-Davidson Big Twins - CAD Plated - OEM #7055
$4.76

Colony #3752-1 Seat Mounting Screw 1/4-28 x 1/2 Harley-Davidson OEM #2739 - Chrome Plated
$4.40

Colony #3749-2 Magneto To Crankase Seal Kit 1958-1965 Harley-Davidson XLCH
$4.40

Colony #3697-4 Exhaust Port Nuts 1984-1999 Harley-Davidson Big Twin 1986-Up XL 1999-Up Twin Cam - Zinc Plated
2 reviews $4.40

Colony #8211-2 Sprocket Shaft Seal Assembly 1939-1973 Harley-Davidson 45's
4 reviews $3.89

Gasbox Replacement Hardware for Gasbox Universal Battery Box - Antigravity 12 Cell
$3.03

Gasbox Replacement Motor Mount Spacer for Gasbox 1986-2003 Sportster Full Rigid Frames
$1.47

Shinko Motorcycle Tires SR777 Rear Motorcycle Tire - 160/70-17
$219.95

Hawg Supply Flatty 4" Air Cleaner CV Carburetor - Brushed Aluminum
$189.99

Hawg Supply Watson 4" Air Cleaner CV Carburetor - Brushed Aluminum
$189.99

Lowbrow Customs Distributor Hold Down Clamp 1952-1970 Harley-Davidson XL 1936-1973 WL
$18.73

Cannonball SSK-R Speedometer Sensor Hole Plug
$66.63

Cannonball Stealthstarter Electric Starter Kit for Rigid Frame Harley-Davidson Big Twins with Baker 6-in-4 Gearboxes
$4,454.00

Lowbrow Customs Jiffy Stand Kickstand Mounting Pin & Screw - 1954-E1984 Harley-Davidson Sportster OEM #50090-53
$7.69

Lowbrow Customs Straton Springer Front End - 22" Length (4" Over) - Black
$1,099.00

Lowbrow Customs Straton Springer Front End - 22" Length (4" Over) - Chrome
$1,199.00

Lowbrow Customs Straton Springer Front End - 20" Length (2" Over Std.) - Chrome
$1,199.00

Lowbrow Customs Straton Springer Front End - 18" Length (Std.) - Chrome
$1,199.00

Lowbrow Customs Straton Springer Front End - 16" Length (2" Under Std.) - Chrome
$1,199.00

Cycle Electric Alternator Kit CE-87T 2012-2017 Harley-Davidson Dyna
$551.81 $590.69

Cycle Electric Alternator Kit CE-86T 2008-2011 Harley-Davidson Softail
$699.49 $748.78

Cycle Electric Alternator Kit CE-84T-14 80 Series 50 Amp 2014-2016 Harley-Davidson FLH/FLT - Air Cooled
$557.29 $596.55

Cycle Electric Alternator Kit CE-84T-10 2009-2010 Harley-Davidson FLH/FLT With Oil Cooler
$700.75 $750.13

Cycle Electric Alternator Kit CE-84T-09 2009-2010 Harley-Davidson FLH/FLT Without Oil Cooler
$703.89 $753.49

Cycle Electric Alternator Kit CE-83T 2007 Harley-Davidson Softail
1 review $708.47 $758.39

Haifley Seats Cobra Seat - Black Diamond - 2004-2021 (Excl. 2007-09) Harley-Davidson Sportsters
$350.00

Cycle Electric Alternator Kit CE-69S-04 2004-2006 Harley-Davidson 1200 Sportster - Upgrade to Three Phase
$641.57 $686.78

Cycle Electric Alternator Kit CE-64T for 2004-2005 Harley-Davidson FXD and Dyna Models
$459.17 $491.52

Cycle Electric Alternator Kit CE-63T for 2001-2006 Harley-Davidson Softail Models
$446.89 $478.38

Cycle Electric Alternator Kit CE-60AR for 1970-1984 Harley-Davidson 4 Speed Solid Mount Motors
$470.33 $503.46

Cycle Electric Alternator Kit CE-32TR for Harley-Davidson Twin Cam Models
$380.94 $407.79

Cycle Electric Alternator Kit CE-24S-09 for 2008-2012 Harley-Davidson XR1200 2009-2013 1200 Sportsters
$527.62 $564.79

Cycle Electric Alternator Kit CE-24S-07 for 2007-2008 Harley-Davidson 1200 Sportsters
$527.62 $564.79

Cycle Electric Alternator Kit CE-23S-09 for 2009-2013 Harley-Davidson 883 Sportsters
$527.62 $564.79

Cycle Electric Alternator Kit CE-23S-04 for 2004-2006 Harley-Davidson 883 Sportsters
$541.41 $579.56

Cycle Electric Alternator Kit CE-22AR for 1970-1988 Harley-Davidson Big Twins
$362.34 $387.87

Gasbox Replacement Tabs for Lowbrow Customs Weld-On Hardtail Frame for 2004-2022 Harley Sportster
$1.62

Gasbox Replacement Hardware for Gasbox Universal Battery Box - YTZ-12S / RTX5L-BS Batteries
$3.08

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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