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

Cannonball Stealthstarter Electric Starter Kit Rigid Frame 3 & 4 Speed Harley-Davidson Big Twins
3 reviews $3,894.96

Shinko Motorcycle Tires Super Classic 270 Front/Rear Motorcycle Tire - 5.00-16 72H
18 reviews $144.95

Bates Baja 100 Tire 16" - 5.00-16 71T
11 reviews $270.98

Belt Drives LTD. 2" SS Belt Drive - Without Cover - 1990-2006 Harley-Davidson FXST/FLST
$2,790.51 $2,937.38

Lowbrow Customs 21" Front Ribbed Spool Wheel - Chrome
24 reviews $346.78

Lowbrow Customs Frisco Mount Sportster Gas Tank - Standard Width - Bayonet Filler - 2.5 gallon
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Shinko Motorcycle Tires Super Classic 270 Front Motorcycle Tire - 3.00-21 57S
17 reviews $116.99

Mid-USA 6 Speed Transmission - Cast Finish - 1990-1999 Harley-Davidson Softail
$1,089.00 $1,414.70

Lowbrow Customs Straton Springer Front End - 24" Length (6" Over) - Chrome
$1,199.00

Lowbrow Customs Weld-On Hardtail Frame for 1982-2003 Harley-Davidson Sportster
97 reviews $447.19

Lowbrow Customs Manta Ray Smooth Steel Fender 6 inch Width
78 reviews $207.12

Top view Frisco mount Sportster Gas Tank by Lowbrow Customs — Lowbrow Customs Frisco Mount Sportster Gas Tank - Standard Width - 2.5 gallon
110 reviews $218.88

Lowbrow Customs Straton Springer Front End - 18" Length (Std.) - Black
$1,099.00

Shinko Motorcycle Tires Shinko Motorcycle Tires Classic 240 Front/Rear Motorcycle Tire - MT90-16 74H
9 reviews $153.95

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 Horseshoe Oil Tank for Lowbrow Customs Weld-On Sportster Hardtails and Gasbox Full Frames
50 reviews $311.99

Antigravity Batteries Antigravity Lithium Small Case Battery - 12 Cell - AG-1201
39 reviews $219.99

Lowbrow Customs Weld-On Ironhead Hardtail Rear Frame Section for 1952-1981 Harley-Davidson Sportster
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Mid-USA 16 x 3.00 Chrome Complete Front / Rear Wheel fits Harley-Davidson Big Twins 1973-1984
16 reviews $202.75

Lowbrow Customs Manta Ray Smooth Steel Fender 4-3/4 inch Width
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Gasbox Bolt-On Oil Tank for Rigid Harley-Davidson Big Twin Frames with Electric Start
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Lowbrow Customs Rogue Fender - 1958-84 Harley-Davidson Panhead Shovelhead
130 reviews $318.57

Cycle Standard Wassell Peanut Mid-Tunnel Gas Tank 2.1 gallon
45 reviews $220.00

Lowbrow Customs Weld-On Hardtail Frame for 2004-2022 Harley-Davidson Sportster
12 reviews $468.00

Cycle Standard 39MM Chrome Fork Tubes - 31 inch - 6 Over
22 reviews $257.77

Gasbox Reno Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 4 Speed - 2" Up - Frisco Tank Mounts
$1,499.00

Cycle Standard Sportster Style Frisco Mount Gas Tank - Narrow - 2.1 gallon
19 reviews $201.99

Lowbrow Customs Straton Springer Front End - 24" Length (6" Over) - Black
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Lowbrow Customs T-Bars Handlebars - 10 inch Rise - 1-Inch Diameter - Chrome
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Cannonball Stealthstarter Electric Starter Kit Swingarm Frame 4 Speed 1958-1985 Harley-Davidson Big Twins
1 review $4,260.63

Cycle Standard Ribbed Steel Fender 5 inch Width
12 reviews $169.33

S&S Cycle S&S Super E Carburetor Assembly - fits Harley Big Twin & Sportster
16 reviews $499.95

Jims USA 6 Speed Overdrive Transmission - Plain Case - 1991-1999 Harley-Davidson Softail
$3,964.00

Mid-USA 6 Speed Transmission - Polished Finish - 1990-1999 Harley-Davidson Softail
2 reviews $1,289.00 $1,451.70

Lowbrow Customs Frisco Mount Sportster Gas Tank - Narrow - 2.1 gallon
69 reviews $232.63

Cycle Electric Alternator Kit 32 amp CE-32AR for Harley-Davidson Evo Big Twins
4 reviews $367.45 $393.34

Prism Supply Co. 4-1/2 inch Round LED Headlight
7 reviews $189.99

Gasbox Reno Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 5 Speed - 2" Up - Frisco Tank Mounts - Horseshoe Oil Tank
$1,799.00

Gasbox Reno Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 4 Speed - 2" Up - Frisco Tank Mounts - Horseshoe Oil Tank
$1,799.00

Gasbox Full Rigid Frame 1936-1999 Harley-Davidson Big Twin 5 Speed - Frisco Tank Mounts - Horseshoe Oil Tank
$1,799.00

Cycle Standard 39MM Chrome Fork Tubes - 29 inch - 4 Over
6 reviews $252.07

Lowbrow Customs Four Piston Brake Caliper - Chrome
1 review $249.00

Lowbrow Customs Complete Solid Motor Mount Kit for 2004 - Up Harley-Davidson Sportster XL
25 reviews $153.52

Gasbox Upswept Exhaust Pipe Set for 1970-1984 Harley-Davidson Shovelhead Rigid Applications
1 review $329.95

Cycle Electric CE-84T-99 Stator Rotor and Regulator Kit for 1999 - 2003 Harley-Davidson FLH and FLT Models
21 reviews $545.16 $583.57

Til Death Cycles 39mm Extended Damper Tube Kit- Harley-Davidson Front End
29 reviews $104.95

Gasbox Full Rigid Chopper Frame 1986-2003 Harley-Davidson Sportsters - 3" Up - Sporty Tank Mounts - Horseshoe Oil Tank
$1,599.00

Lowbrow Customs Shotgun Exhaust Pipes 1990-2003 Harley-Davidson Sportster XL Chrome
60 reviews $353.49

Lowbrow Customs T-Bars Handlebars - 12 Inch Rise - 1 inch Diameter - Chrome
5 reviews $144.14

Bob Newby Racing Belt Drive and Clutch for Triumph Unit 650 c.c. T120 TR6
10 reviews $1,051.69

Gasbox Exhaust Pipe Set 2-into-1 1970-84 Harley Cone Shovelhead - Chrome OEM #65435-70
15 reviews $279.99

Cycle Standard Stock Style Harley Sportster Gas Tank 1986 - 2003 - Left Side Petcock - 2.2 gallon
72 reviews $218.85

Gasbox Bolt-On Horseshoe Oil Tank for 1965-Up Harley Four-Speed Swingarm Frames
30 reviews $299.99

Gasbox Reno Full Rigid Chopper Frame 1936-1999 Harley-Davidson Big Twin 5 Speed - 2" Up - Frisco Tank Mounts
1 review $1,499.00

S&S Cycle S&S Super E Carburetor Rebuild Kit #11-2923 for Harley Davidson
29 reviews $105.95

Belt Drives LTD. 2" Open Belt Drive Kit - Polished - 1990-2006 Harley-Davidson FXST/FLST
2 reviews $2,958.01 $3,113.69

Cycle Standard 39MM Chrome Fork Tubes - 27 inch - 2 Over
2 reviews $209.58

American Prime Mfg. Brake/Mechanical Clutch Control Kit for 1 inch Handlebars - 11/16 inch Bore - Polished
1 review $366.14

American Prime Mfg. Brake/Mechanical Clutch Control Kit for 1 inch Handlebars - 9/16 inch Bore - Polished
5 reviews $366.14

Lowbrow Customs Bolt-On Hardtail Frame 1963-1970 Triumph - Unit 650 c.c.
40 reviews $363.99

Belt Drives LTD. 8mm/1.5 inch Primary Belt Drive - Kick Start - 1965-1978 Harley-Davidson Big Twins
$726.39 $764.62

Gasbox Steel 16 inch Fender for Vintage Style Tires
48 reviews $169.99

Lowbrow Customs Original P-Nut Tank Deep Tunnel Gas Tank 1.8 gallon
62 reviews $205.99

Cycle Standard Wassell Peanut Gas Tank - 2 Gallon - Deep Tunnel - Dual 1/4" NPT
10 reviews $220.00

Lowbrow Customs Springer Top Clamp for Standard 3.5" Handlebar Risers
3 reviews $202.45

Cycle Standard 39MM Chrome Fork Tubes - 35 inch - 10 Over
$313.69

Diamond 530 Drive Chain - 120 links USA made
21 reviews $174.56 $193.95

Morris Magneto MM3 Magneto for Harley Davidson Sportster 1957 - 1970 and 45 and 80 Flatheads - Brushed Finish
3 reviews $1,359.75

Morris Magneto MM74e Magneto for Harley Davidson Big Twins 1936 - 1969 Pan / Shovel - Brushed Finish
6 reviews $1,359.75

Lowbrow Customs Rabbit Ears Handlebars - 1 inch - Chrome
37 reviews From $142.66

Timken Neck Post Bearing & Race Set - Made in USA
18 reviews $28.14

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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