Which models are considered Big Twins?

Big Twins refer to larger displacement Harley-Davidsons, including Flathead, Knucklehead, Panhead, Shovelhead, Evo, and Twin Cam.

Do I need any special tools for installing custom Big Twin parts?

Basic hand tools usually suffice, but some installations (like welding) may require specialized equipment or professional assistance.

Can I return items if they don’t fit my Big Twin?

Absolutely. As long as the part is in original, unused condition, you can return it according to our standard return policy.

Harley-Davidson Big Twin Parts

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Colony #7811-14 Inner Primary Mounting Kit - 1936-1954 Harley-Davidson Knucklehead/Panhead
1 review $26.08

Colony #8707-6 Tappet Oil Screen/Oil Pump Check Valve/Relief Valve Plug Set 1981-Up Harley-Davidson Big Twin OEM #26263-80 - Chrome Plated
4 reviews $26.07

James Gaskets 4 Speed Transmission End Cover Gasket 1936-1986 Harley-Davidson Big Twin
1 review $6.46

Cycle Standard Throttle Cable OEM #56356-96A Harley Dyna 1996-2008
4 reviews $38.62

Drag Specialties Chrome Rear Axle Kit 1973-1983 Harley-Davidson FL/FX OEM# 41552-73
1 review $61.53 $76.91

James Gaskets Replacement Float Bowl O-ring for 1992-2006 Harley-Davidson CV Carbs
$6.96

Colony 8749-12 Transmission Top Cover Allen Screw Kit 1965-1978 Harley-Davidson Big Twin - CAD Plated
1 review $25.41

Cycle Standard Reproduction Long Skirted Eaton Style Bayonet / Cam Style Vented Gas Cap - Chrome
23 reviews $38.04

Colony #8012-2 Intake Manifold Nuts 1930-1948 Harley-Davidson 74 & 80 c.i. Flathead 1936-1939 61 c.i. OHV & 1940-1946 WLD - Chrome Plated
$38.03

Cycle Standard Throttle Idle Cable OEM #56355-96A Harley Dyna 1996-2008
1 review $38.01

Cycle Standard Shift Lever - 1985-2006 Harley-Davidson Big Twin/Twin Cam - Chrome - OEM #33715-85A
1 review $25.33

Lowbrow Customs Lowbrow Customs Spark Plug Wire Set 1986-2003 Harley-Davidson XL 1980-1989 FLH/FLT
$25.29

Cycle Standard Throttle Cable OEM #56356-92 Harley Dyna 1992-1995 +4 inch Extended
$25.28

Lowbrow Customs Cast Aluminum Knurled Oil Tank Plug - Semi Polished
4 reviews $25.26

Cycle Standard Replacement Lower 39mm Damper Springs 1987-Up Harley-Davidson XL 1991-2005 FXD 1987-1994 FXR OEM# 45374-87
$18.89

Colony #7103-2 Intake Manifold Nuts - 1940-1954 Overhead Valve Harley-Davidson 74's 1953-56 K/KH - Chrome Plated
$37.66

Colony #3667-19 Primary Cover Screw Kit 1989-2006 Harley-Davidson Softail 1991-2005 Dyna - CAD Plated
4 reviews $25.08

Unity Manufacturing Four Speed Transmission Mainshaft Nut Wrench Adapter
$25.00

Gasbox Front Motor Mount Spacer Plate Harley-Davidson Knucklehead Panhead UL OEM #438-48 24795-48
5 reviews $15.00

Fast Eddy Co. No. 66 Engine Rotation Socket for 1954-Earlier Harley-Davidson with Tapered Shaft
$74.95

Fast Eddy Co. No. 67 Plumber Nut Intake Wrench 2-1/8" for 1941-1954 Harley-Davidson FL Large Style Intakes
$74.95

Gasbox Strong Arm Top Engine Mount For Early Big Twin Engines In Gasbox Frames
$74.95

Gasbox Strong Arm Top Motor Mount - 1984-1999 Harley-Davidson Big Twin Evolution
$74.95

Fast Eddy Co. No. 24 Engine Rotation Socket - 24 Spline for 2007-Up Harley-Davidson Big Twin
$74.95

Fast Eddy Co. No. 22 Engine Rotation Socket - 10 Spline for 1955-2006 Harley-Davidson Big Twin
4 reviews $74.95

PanAm Oils Inc. Oil Pressure Gauge 0-60 psi - Black
9 reviews $37.15

Colony #3662-5 Disc Rotor Allen Screw & Nut Kit 1979-1991 Harley-Davidson XL/FX (Cast Wheel) - Chrome Plated
1 review $14.85

Colony #2433-18 Sidecar Body Support Rods Repair Kit 1941-1993 Harley-Davidson
1 review $73.37

Colony #9532-13 Rear Crash Bar Mounting Kit 1936-1957 Harley-Davidson Big Twin - Parkerized
1 review $36.54

Colony #2146-2 Tappet Oil Screen & Spring 1970-1999 Harley-Davidson Big Twin
2 reviews $10.42

Colony #3544-3 Oil Line Nuts 1915-1964 Harley-Davidson All Models OEM #3581-15 - CAD Plated
$14.52

James Gaskets Primary Cover Gasket 1983-1993 Harley-Davidson Softail & Dyna Models
$36.23

Cycle Standard Transmission Seal and Quad O-ring OEM# 12067A
$10.35

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

Colony #2988-3 Crankcase Breather Stud and Pipe 1939-1947 Harley-Davidson Knuckleheads - Parkerized
$36.00

Cycle Standard Replacement Dished Sprocket - Black - 47 Tooth - 1973-1985 Harley-Davidson Big Twin 1979-81 XL
$71.89

Drag Specialties 50A Circuit Breaker 1970-1999 Harley-Davidson Big Twin/XL 1999 Twin Cam
$11.95

Colony #3056-1 Pushrod Lifter ToolHarley-Davidson Knucklehead Panhead Shovelhead
1 review $71.50

Cycle Standard 35mm Fork Seal Rebuild Kit - Showa Forks - 1984-87 Harley-Davidson XL FX FXR
6 reviews $17.85

Cycle Standard Blackout Taillight 1999-2015 Harley-Davidson FL/FX/Sportster (except 12-15 XL1200C/CP)
2 reviews $71.27

Cycle Standard Filler Neck- Thread In Style Gas Cap Weld In Bung- Right Hand Thread -1996 & Up Caps - Vented
8 reviews $14.22

Lowbrow Customs Air Cleaner Backplate Gasket for CV Carburetor
28 reviews $2.22

Colony #2091-12 Replacement Pushrod Covers Late 1979-1984 Harley-Davidson Shovelhead - Chrome Plated
3 reviews $70.39

Cycle Standard Transmission Sprocket .5" Offset - 22 Tooth - 1991-2006 Harley-Davidson XL 1986-2006 Big Twin 5-Speed
$70.34

Gasbox Front Exhaust Pipe 1948-1965 Harley-Davidson Panhead - Chrome - OEM #65440-48
2 reviews $70.00

Colony #9639-22 Electrical Terminal Plate 1970-1977 Harley-Davidson FL/FX - CAD Plated
$35.00

Gasbox Custom Kickstand Bracket for Gasbox Big Twin Frames
$69.95

Fast Eddy Co. No. 69 Plumber Nut Intake Wrench 1-7/8" for all Harley-Davidson 45 c.i. Flat Heads Small Style Intakes
$69.95

Fiorucci Fabrications Harley Big Twin Rigid Oil Tank 12V Battery Box for RTX5L-BS Battery
1 review $69.95

Gasbox Axle Plate License Plate Bracket for 1936 - 1957 Harley-Davidson Big Twin Rigid Frames
4 reviews $69.95

Colony #9720-1 Stem Nut 1936-1948 Harley-Davidson Big Twin Springers - Parkerized
3 reviews $13.94

Colony #9892-18 Gas Tank Mounting Kit 1937-1975 Harley-Davidson Big Twin 1972-1972 FX - CAD Plated
6 reviews $17.42

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

Colony #3193-2 Primary Drain Plug 2004-2006 Harley-Davidson Softail - Zinc Plated
10 reviews $11.50

Drag Specialties Swing Arm Bearing Kit 1984-99 Harley-Davidson FXST/FLST
$68.75

Drag Specialties Breaker Plate Assembly 1970-1999 Harley Davidson Big Twin 1971-2003 XL Points Ignition (Except Single Fire Ignition)
$17.12

Colony #9978-2 Custom Fork Stem Bolt 1986-Up Harley-Davidson XL/FXR/FXD/FLST - Chrome Plated
3 reviews $22.80

Colony #7808-4 Upper Pushrod Covers (Inner) 1957-1985 Harley-Davidson Sportster 1936-Early 1979 OHV Big Twins
3 reviews $34.05

Cycle Standard Transmission Sprocket Spacer OEM# 33344-94
1 review $8.44

Colony #9419-19 Transmission Mounting Kit 1965-Early 1977 Harley-Davidson Big Twin - Zinc Plated
4 reviews $33.67

The Rough Trade Axle Wrench for Harley-Davidson Big Twin
$22.31

#2399-2 Stem Nut Stock Zinc OEM 45718-71 Harley FX FXR 71-87 XL 78-87 — Colony #2399-2 Stem Nut Stock 1971-1987 Harley-Davidson FX/FXR 1978-1987 XL - Zinc Plated
5 reviews $16.70

Colony #2428-6 Handlebar Damper Kit 1973-Up Harley-Davidson Big Twin/Sportster
12 reviews $16.70

Drag Specialties Shifter Linkage - Black - 1984-2021 Harley-Davidson FLHT/FLHR/FLHX/FLTRX/FLTRU 2000-17 FLST/FLS
$66.73

Cannonball SSK-R Speedometer Sensor Hole Plug
$66.63

Colony #2595-13 Top Motor Mount Hardware 1952-1972 Harley-Davidson Big Twin 1957-1972 Sportster - CAD Plated
3 reviews $22.00

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

Colony #8879-30 Rear Fender Support Mounting Kit 1958-1980 Harley-Davidson FL/FLH - Chrome Plated
4 reviews $33.00

Standard Motorcycle Products Ignition Sensor Assembly - 1980-1994 Harley-Davidson XL 1984-1985 FXST 1980-1993 FLT
3 reviews $65.95

Koyo Bearings Neck Post Bearing & Race Set - Made in Japan
$21.95

Cycle Standard Throttle Cable OEM #56356-92 Harley Dyna 1992-1995 - Blacked Out
2 reviews $16.45 $23.50

James Gaskets Exhaust Port Gaskets - STD Heads for Harley-Davidson Shovelheads
$13.13

Harley-Davidson Big Twin motorcycles are legendary for their raw power, distinctive style, and unmatched capacity for customization. From the Flathead and Knucklehead to the Panhead, Shovelhead, Evo, and Twin Cam, each Big Twin engine carries its...

If you’re looking to transform your ride—enhancing speed, comfort, or that unmistakable retro look—explore our Harley-Davidson Big Twin Parts collection. We have everything you need to customize your bike, whether you’re focusing on performance upgrades or eye-catching aesthetics.

Why Upgrade a Harley-Davidson Big Twin?

Boundless Customization: Big Twins allow for radical transformations—from stripped-down bobbers to vintage choppers—letting you express your unique vision.
Enhanced Performance: Boost horsepower, torque, and responsiveness with high-quality ignition kits, carburetors, and more.
Personalized Aesthetics: Whether it’s a retro-inspired racer or a comfortable tourer, your bike can reflect your style and riding needs.

Why Buy Big Twin Motorcycle Parts at Lowbrow Customs?

We curate top brands and rigorously test products for durability, fitment, and performance before shipping them out.
Variety of Choices: We offer a carefully curated selection of motorcycle parts for a wide range of Big Twin engines—from the Flathead and Knucklehead to the Panhead, Shovelhead, Evo, and Twin Cam—so you can find the perfect fit for your ride.
Expert Guidance: Need advice on installing a gas tank or swapping out your ignition? Our dedicated staff is here to help—from how-to videos to step-by-step articles.
Passion for Custom Builds: We’re not just sellers—we’re fellow riders who believe in the art of motorcycle customization. Count on our expertise to bring your dream bike to life.
Wide Selection & Fast Shipping: Our warehouse in northeast Ohio is stocked daily, ensuring you get the parts you need quickly. Plus, enjoy free economy shipping on U.S. orders over $99 and flexible return policy within 90-day & no return fee.

Our Featured Big Twin Motorcycle Parts Products

Ignition Kits & Carburetors: Gain more power and better throttle response by upgrading your ignition and carb system. A refined setup can increase speed, torque, and overall rideability.
Custom Gas Tanks: Our Big Twin gas tanks are crafted from high-grade steel, pressure-tested to prevent leaks, and available in multiple shapes and capacities. Achieve the perfect balance between form and function.
Handlebars & Controls: From vintage ape hangers to sporty drag bars, our collection of handlebars offers different heights, widths, and designs. Complete the setup with controls like grips, mirrors, and brake/clutch assemblies for a cohesive look.
Retro Accessories: Elevate your Big Twin’s retro appeal with add-ons like vintage-inspired seats, windshield options, saddle bags, or even a top-mounted box for touring. Personalizing these details completes the old-school charm.

Ready to Customize Your Harley-Davidson Big Twin?

Explore our Harley-Davidson Big Twin Parts collection today and transform your ride into the perfect blend of power, comfort, and style. If you have questions, reach out to our expert support team or dive into our installation guides for pro tips. Let’s make your dream bike a reality—shop now and gear up for the open road.

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Harley-Davidson Big Twin Parts FAQ

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