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 #9866-18 Transmission Mounting Kit 1986-Up Harley-Davidson FXST - Chrome Plated
$26.07

Colony #9827-12 Timing Cover Allen Screw Kit 1/4-20 1936-1970 Harley-Davidson After Market Cases - Chrome Plated
1 review $24.62

Colony #9833-24 Rocker Cover Allen Screw Kit 1985-Up Harley-Davidson FL/FX 1986-Up XL - Chrome Plated
3 reviews $23.91

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

Colony #9423-1 Threaded Cylinder Head to Manifold Nipple 1930-1948 Harley-Davidson 74 & 80 Sidevalves
1 review $22.80

Colony #9618-18 Jiffy Stand & Foot Clutch Lever Bracket Mounting Kit 1936-1978 Harley-Davidson Big Twin - CAD Plated
1 review $26.40

Colony #9612-13 Transmission Top Cover Screw Kit 1936-1955 Harley-Davidson Big Twin - Chrome Plated
$23.90

Colony #9412-19 Timing Cover Screw Kit 1937-1973 Harley-Davidson 45's - Chrome Plated
$30.87

Colony #9410-27 Transmission Top & Side Cover Screw Kit 1937-1973 Harley-Davidson 45's - Chrome Plated
1 review $20.27

Colony #9794-12 Timing Cover Screw Kit 1/4-20 After Market Harley-Davidson Cases - Chrome Plated
$24.20

Colony #9778-8 Handlebar Lever & Switch Housing Mount Acorn Screw Kit 1996-Up Harley-Davidson Dyna/Softail 1996-2003 XL - Chrome Plated
$20.27

Colony #9630-2 Front Brake Cable Adjusting Screw 1941-1948 Harley-Davidson Big Twin 1941-1957 45 Servicar - Parkerized
$21.12

Colony #9867-18 Transmission Mounting Kit 1986-Up Harley-Davidson FXST - Zinc Plated
$20.70

Colony #9699-12 Rocker Box Mounting Kit 1936-1947 Harley-Davidson Knucklehead - Parkerized
$19.51

Colony #9406-3 Front Axle Nut Kit 1930-1936 Harley-Davidson VL 1936-1945 Big Twins - Parkerized
$19.93

Colony #9741-2 Front Brake Cable Adjuster 1950-1971 Harley-Davidson Big Twin 1971-1972 FX 1952-1972 XL - Chrome Plated
1 review $18.72

Colony #9677-4 Rear Brake Cross Shaft Nut & Lock Kit 1930-1957 Harley-Davidson Big Twins - Parkerized
2 reviews $17.92

Colony #9514-2 Handlebar Plunger 1954-1974 Harley-Davidson FL 1971-1973 FX 1954-1973 XL 1954-1973 Servicar
$18.72

Colony #9308-17 Primary Cover Screw Kit 1970-1980 Harley-Davidson Shovelhead - CAD Plated
$17.99

Colony #9620-13 Transmission Top Cover Screw Kit 1936-1955 Harley-Davidson Big Twin - Parkerized
1 review $17.88

Colony #9613-13 Transmission Top Cover Screw Kit 1936-1955 Harley-Davidson Big Twin - CAD Plated
$19.71

Colony #9411-27 Transmission Top & Side Cover Screw Kit 1937-1973 Harley-Davidson 45's - CAD Plated
$17.92

Colony #9796-12 Timing Cover Screw Kit 1/4-20 After Market Harley-Davidson Cases - Parkerized
$21.30

Colony #9795-12 Timing Cover Screw Kit 1/4-20 After Market Harley-Davidson Cases - CAD Plated
$21.30

Colony #9789-17 Transmission Shifter Cover Allen Screw Hardware Kit 1991-Up Harley-Davidson Dyna - Chrome Plated
$17.14

Colony #9400-1 Steel Transmission Filler Plug 1958-1980 Harley-Davidson Big Twin - Chrome Plated
1 review $17.52

Colony #9102-8 Cylinder Base Nut Set 1978-1984 Harley-Davidson Shovelhead OEM #16838-78 - Black Oxide
2 reviews $20.35

Colony #9101-8 Cylinder Base Nut Set Zinc 1978-1984 Harley-Davidson Shovelhead OEM #16838-78 - Zinc Plated
1 review $20.35

Colony #9817-15 Electrical Terminal Plate 1970-1974 Harley-Davidson FX/XL - Parkerized
2 reviews $25.00

Colony #9762-16 Oil Pump Mounting Kit Allen 1992-Up Harley-Davidson Big Twin - Chrome Plated
1 review $16.38

Colony #9636-8 Handlebar Clamp & Gauge Mount Kit 1983-1994 Harley-Davidson FX/XL - Chrome Plated
$15.94

Colony #9623-16 Cylinder Base Nuts 1936-1978 Harley-Davidson Big Twins - Parkerized
3 reviews $15.64

Colony #9737-1 Gear Box Adjusting Screw 1936-1964 Harley-Davidson Big Twin - Parkerized
1 review $15.52

Colony #9622-16 Lifter Base Screw Kit 1936-1953 Harley-Davidson Big Twin 1937-1973 45's - Parkerized
2 reviews $16.35

Colony #9401-1 Aluminum Transmission Filler Plug 1958-1980 Harley-Davidson Big Twin
2 reviews $15.52

Colony #9834-8 Chrome Countersink Washer Set for 1/4" Flat Head Socket Harley-Davidson - Chrome Plated
$15.14

Colony #9607-2 Oil Pump Relief Valve Plug 1968-1980 Harley-Davidson Big Twin - Chrome Plated
$15.14

Colony #9605-2 Oil Pump Relief Valve Plug 1954-1967 Harley-Davidson Big Twin - Chrome Plated
3 reviews $15.14

Colony #9107-8 Rear Brake Caliper Anchor Arm Bolt Kit 1973-1983 Harley-Davidson FL/FX - CAD Plated
1 review $15.13

Colony #9017-5 Air Cleaner Mounting Screw & Lock Kit 1936-1955 Harley-Davidson Twins - CAD Plated
$16.94

Colony #9682-5 Air Cleaner Mounting Screw & Lock Kit 1936-1955 Harley-Davidson Twins - Parkerized
1 review $16.94

Colony #9603-2 Oil Screen Plug 1952-1965 Harley-Davidson Big Twin - Chrome Plated
$14.34

Colony #9863-5 Transmission Case Bottom Stud Kit 1984-Up Harley-Davidson Softail
1 review $13.55

Colony #9633-50 Flatwashers Harley-Davidson FL/FX/XL OEM #6099 - Chrome Plated
7 reviews $14.52

Colony #9644-2 Oil Screen Plug 1981-Up Harley-Davidson FL/FX - Chrome Plated
$11.96

Colony #9526-1 Oil Pump Bypass Valve Plug 1936-1952 Harley-Davidson Big Twin 1937-Up UL/45s - Chrome Plated
$11.96

Colony #9819-12 Timing Cover Allen Screw Kit 1993-Up Harley-Davidson Big Twin - Chrome Plated
2 reviews $11.90

Colony #9604-2 Oil Screen Plug 1952-1965 Harley-Davidson Big Twin - CAD Plated
$11.14

Colony #9600-5 Disc Brake Rotor to Hub Allen Screw Kit 1974-1980 Harley-Davidson FX 1974-1977 XL - Chrome Plated
$10.76

Colony #9204-3 Clutch Lever Rod Bolt 1952-1964 Harley-Davidson Big Twin OEM #36921-52 - CAD Plated
$10.37

Colony #9706-4 Shifter Rod End Bolt Kit 1936-1954 Harley-Davidson Handshift 1951-1964 Footshift - Parkerized
$9.96

Colony #9671-20 Transmission Side Cover & Clutch Arm Nut Kit Pre-1984 Harley-Davidson 4 Speed - Parkerized
4 reviews $9.96

Colony #9109-2 Generator Screws 1930-1948 Harley-Davidson Big Twin Sidevalves OEM #1523-30 - CAD Plated
2 reviews $10.37

Colony #9672-8 Linkert Carb Mounting Screws Harley-Davidson OEM #27422-39 - Parkerized
2 reviews $9.56

Colony #9527-1 Oil Pump Bypass Valve Plug 1936-1952 Harley-Davidson Big Twin 1937-Up UL/45s - CAD Plated
$9.56

Colony #9787-12 Oil Pump Mounting Kit Stock 1978-1991 Harley-Davidson Big Twins - Zinc Plated
$8.78

Colony #9502-1 Timing & Oil Tank Plug 1938-1951 Harley-Davidson All Models OEM #2326-38 - Chrome Plated
$9.56

Colony #9304-1 Oversize Harley-Davidson Timing & Oil Tank Plug - Chrome Plated
1 review $8.78

Colony #9840-8 Chrome OEM Style Rocker Shaft End Nut 1936-1947 Harley-Davidson Knucklehead - Chrome Plated
$9.16

Colony #9649-5 Speedometer Cable Clamp 1939-1948 Harley-Davidson 74/80 Sidevalve - Parkerized
$13.20

Colony #9645-2 Oil Screen Plug 1981-Up Harley-Davidson FL/FX - CAD Plated
$7.96

Colony #9687-5 Transmission Screw Kit 1929-1973 Harley-Davidson 45's - Parkerized
$9.10

Colony #9651-1 Speedometer Cable Clamp 1957-1961 Harley-Davidson OHV Big Twins - Parkerized
$7.58

Colony #9650-1 Speedometer Cable Clamp 1952-1956 Harley-Davidson OHV Big Twins - Parkerized
$7.58

Colony #9646-1 Speedometer Cable Clamp 1936-1938 Harley-Davidson 74/80 Sidevalve 1936-1951 61/74 OHV - Parkerized
2 reviews $7.58

Colony #9652-1 Speedometer Cable Clamp 1961-1980 Harley-Davidson OHV Big Twins - Zinc Plated
$7.17

Colony #9704-10 Cylinder Head Bolt Washers 1936-Up Harley-Davidson - Parkerized
$6.78

Colony #9520-4 Generator Pole Screw Kit 1918-1957 Harley-Davidson Twins OEM #30280-18 - Parkerized
$6.78

Colony #9508-4 Handlebar Bolt Kit 1936-1948 Harley-Davidson Big Twin Springers 1940-Up 45 Springers - Parkerized
$9.68

Colony #9504-1 Timing & Oil Tank Plug 1938-1951 Harley-Davidson All Models OEM #2326-38 - Parkerized
1 review $8.80

Colony #9218-4 Handlebar Bolt Kit Harley-Davidson 1936-1948 Big Twin Springers 1940-Up 45 Springers - CAD Plated
$9.68

Colony #9841-8 Rocker Shaft End Nut Kit 1936-1947 Harley-Davidson Knucklehead - CAD Plated
$6.38

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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