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 41MM Chrome Fork Tubes 1949-1976 Harley-Davidson FL - 22 inch - 2 Over
1 review $189.55

Mid-USA Rear Master Cylinder - 1958-1972 Harley-Davidson Big Twin - Replaces OEM #41761-58 41761-78
5 reviews $69.95

Custom Cycle Engineering 39MM Ultra Chrome Fork Tubes - 34-1/4 inch
$717.95

Custom Cycle Engineering 39MM Ultra Chrome Fork Tubes - 32-1/4 inch
1 review $717.95

Custom Cycle Engineering 39MM Ultra Chrome Fork Tubes - 24-1/4 inch
$717.95

Progressive Suspension Drop-In Front Fork Lowering Kit - fits 2000-2017 Harley-Davidson FXST FLST
$164.95

Saddlemen Step Up Seat - Tuck and Roll - fits 2004-Up Harley-Davidson Sportsters
$449.00

Saddlemen Step Up Seat - Front Lattice Stitch - fits 2004-Up Harley-Davidson Sportsters
3 reviews $449.00

Drag Specialties Predator 2-Up Seat - Smooth - fits 1986-2003 Harley-Davidson Sportsters
$348.95

Saddlemen Step Up Seat - Lattice Stitched - fits 1977-2003 Harley-Davidson Sportsters
3 reviews $449.00

Saddlemen Step Up Seat - Front Lattice Stitch - fits 1977-2003 Harley-Davidson Sportsters
1 review $449.00

Drag Specialties King and Queen Seat - Diamond - Hardtail Frames
$496.95

Saddlemen Step Up Seat - Tuck and Roll - fits 2006-2017 Harley-Davidson Dynas
2 reviews $459.00

LePera Kickflip Seat - Pleated - fits 1996-2003 Harley-Davidson Dyna
$548.00

LePera Kickflip Seat - Diamond - fits 1996-2003 Harley-Davidson Dyna
$548.00

EMGO Complete Engine Gasket Set with Head Gasket Triumph 750cc 1973-1983 T140 Bonneville TR7
2 reviews $119.86

EMGO Top End Engine Gasket Set with Head Gasket Triumph 750cc 1973-1983 T140 Bonneville TR7
$66.46

Mullins Chain Drive 41mm Super Narrow Triple Trees Set
1 review $500.00

Mullins Chain Drive Richmond Spool Hub - Black
$299.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 16" Ape Hanger Handlebars 2014-Up Harley-Davidson Sportsters without ABS
1 review $273.56 $303.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 14" Ape Hanger Handlebars 2014-Up Harley-Davidson Sportsters without ABS
$273.56 $303.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 12" Ape Hanger Handlebars 2014-Up Harley-Davidson Sportsters without ABS
1 review $273.56 $303.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 12" Ape Hanger Handlebars 2014-Up Harley-Davidson Sportsters Single Brake Disc with ABS
$308.66 $342.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 16" Ape Hanger Handlebars 2007-2013 Harley-Davidson Sportsters
1 review $227.66 $252.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 14" Ape Hanger Handlebars 2007-2013 Harley-Davidson Sportsters
3 reviews $227.66 $252.95

Burly Brand Complete Handlebar Cable/Brake Line Kit for 14" Ape Hanger Handlebars 2004-2006 Harley-Davidson Sportsters
1 review $227.66 $252.95

British Standard Metric Timing Side Crankshaft Bearing for 1972-80 Triumph 650 750 Unit Twin Motorcycles OEM #70-3835
$98.76

British Standard Triumph Patent Plate with Rivets
8 reviews $19.37

Cannonball Intake Manifold for Bendix/Keihin Butterfly Carburetors Harley-Davidson Flatheads U and WLDR 1937 & Up
$228.67

Cannonball Intake Manifold for Bendix/Keihin Butterfly Carburetors 1940-54 Harley-Davidson OHV Models
$268.35

Cannonball Oil Pump 1936-52 Harley-Davidson Knucklehead Panhead - Replaces OEM #26201-41 26201-48
1 review $1,176.02

Cannonball Tappet Guides 1936-47 Harley-Davidson Knucklehead - Replaces OEM #18610-36 18600-36
1 review $1,257.68

Cannonball Harley Flathead Engine Crankcase 1937-1948 - Replaces OEM #24515-37
$5,187.41

Cannonball Crankcases 1948-1952 Harley-Davidson Panhead - Replaces OEM #24520-48
$4,768.57

Cannonball Crankcases 1941-1947 Harley-Davidson Knucklehead - Replaces OEM #24520-41
1 review $4,799.25

Fast Eddy Co. No. 35 Float Bowl Drain Valve for Mikuni Carburetors
4 reviews $44.95

Fast Eddy Co. No. 34 Float Bowl Drain Valve for Amal Carburetors
7 reviews $44.95

Colony #3548-1 Seat Clevis Pin Spring for Short T-bar 1943-1952 Harley-Davidson WLA/WLC - Parkerized
$8.47

Colony #3481-1 Oil Return Elbow 1953-E1962 Harley-Davidson XLCH 1958-1966 XLH - CAD Plated
$27.50

Colony #3469-1 Rear Chain Oiler Tee Fitting 1970-1978 Harley-Davidson FL/FLH/FX - Zinc Plated
$30.80

Cycle Standard Diamond Tail Light - Chrome
4 reviews $56.47

Cycle Standard Cobalt LED Tail Light - Black
1 review $86.26

Cycle Standard Aurora Mini LED Tail Light - Smoke Lens - Black
2 reviews $34.89

Burly Brand Slammer Plus Shocks - 2004 - 2020 Harley-Davidson Sportster XL - Black
4 reviews $364.46 $404.95

Burly Brand Slammer Plus Shocks - 2004 - 2020 Harley-Davidson Sportster XL - Chrome
$364.46 $404.95

Burly Brand Slammer Plus Shocks - 1988 - 2003 Harley-Davidson Sportster XL - Black
1 review $364.46 $404.95

Burly Brand Slammer Suspension Kit - 2006- 2017 Harley-Davidson Dyna FXD - Black
$387.86 $430.95

Burly Brand Slammer Suspension Kit - 2006 - 2017 Harley-Davidson Dyna FXD - Chrome
$387.86 $430.95

Burly Brand Slammer Suspension Kit - 2004 - 2015 Harley-Davidson Sportster XL - Black
$387.86 $430.95

Burly Brand Slammer Suspension Kit - 2004 - 2020 Harley-Davidson Sportster XL - Chrome
$387.86 $430.95

Burly Brand Stiletto Shock - Black - 13.5 inch - 1999 - 2017 Harley-Davidson Dyna Models
2 reviews $341.96 $379.95

Drag Specialties Replacement Shocks - 12.5 inch - 1986 - 2003 Harley-Davidson Sportster XL - Black
$314.95

Mooneyes Dice Air Valve Caps - Blue
1 review $11.20

Colony #3542-1 Speedometer Cable Clip 1954-1965 Harley-Davidson Models - Parkerized
$6.05

Colony #3540-1 Circuit Breaker Timer Wire Cable Clip 1941-1948 Harley-Davidson Big Twins - Parkerized
$6.05

Colony #3390-4 Handlebar Clamp Allen Screw Kit 1982-Up Harley-Davidson FX/XL
3 reviews $6.05

Colony #3518-2 Front Brake Lever Clevis Pin 1952-1972 Harley-Davidson K/KH/XL 1971-1972 FX 1951-1957 Servi-car - CAD Plated
$7.57

Colony #3531-9 Horn Face Screw & Nut Kit 1931-1957 Harley-Davidson Springer Models - CAD Plated
$11.50

Colony #3533-3 Front Brake Cable Clip 1950-1971 Harley-Davidson FL/FLH - CAD Plated
2 reviews $16.34

Colony #3543-6 Gas Tank Name Plate Gaskets 1940-1946 Harley-Davidsons
$17.25

Colony #3538-4 Magneto Vent Cover Kit 1958-1969 Harley-Davidson XLCH/Fairbank Morris/Joe Hunt Magnetos
$20.57

Colony #3532-6 Oil Tank Rubber Washer Kit 1952-1966 Harley-Davidson K/KH/XL
1 review $33.00

Colony #3530-6 Spotlight Clamp Kit 1938-1961 Harley-Davidson Models- Chrome Plated
$35.75

Colony #3539-5 Fork Bracket Bolt & Clip Kit 1950-1957 Harley-Davidson OHV - Parkerized
$56.65

Colony #3448-5 Disc Brake Rotor To Hub Allen Screw Kit 1974-1977 Harley-Davidson FX/XL - Zinc Plated
$7.87

Colony #3438-1 Brake Cross Over Shaft Lever - Left End 1941-1957 Harley-Davidson Sidecars - Parkerized
$38.50

Colony #3436-1 Brake Cross Over Shaft Lever - Brake End 1939-1957 Harley-Davidson Sidecars - Parkerized
$38.50

Colony #3435-1 Cylinder Bracket for Cast Iron Heads 1932-Up Harley-Davidson 45's & Servi-car with Iron Heads - Parkerized
$45.00

Colony #3423-1 Oversized Motor Case Drain Plug Oil Pump Body Plug 7/16-20 1936-1970 Harley-Davidson Big Twin Cases 1937-Up 45 Cases 1968-1984 Oil Pump Body - Parkerized
$5.50

Colony #3422-1 Oversized Motor Case Drain Plug Oil Pump Body Plug 7/16-20 1936-1970 Harley-Davidson Big Twin Cases 1937-Up 45 Cases 1968-1984 Oil Pump Body - Chrome Plated
$6.60

Colony #3197-1 Sidebar Foot Clutch Lever Spring Stud 1932-1936 Harley-Davidson VL
$10.29

Colony #3519-9 Crankcase Relief Pipe Gasket Kit 1937-1973 Harley-Davidson 45s 1937-1948 Sidevalve Models - Parkerized
1 review $7.15

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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Custom Motorcycle Parts FAQ

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