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

Sort by

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

Colony #9814-16 Lifter Base Screw Kit 1/4-20 Harley-Davidson Aftermarket Case - Chrome Plated
1 review $17.69

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 #9864-6 Grease Fitting Zerk Type 1936-1984 Harley-Davidson - CAD Plated
3 reviews $12.74

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

Colony #9523-1 Oil Pump Check Valve Plug 1936-1980 Harley-Davidson Big Twin 1937-Up UL/45s - Chrome Plated
2 reviews $12.74

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 #9305-7 Timing Cover Screw Kit 1970-1980 Harley-Davidson Shovelhead - Chrome Plated
1 review $12.10

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

Colony #9632-5 Rear Cast Wheel Rotor Allen Screw Kit 1979-1991 Harley-Davidson FX/FL 1979-1996 XL - Chrome Plated
1 review $11.14

Colony #9103-4 Shift Rod End Bolt Kit 1936-1954 Harley-Davidson Handshift 1951-1964 Foot Shift - Chrome Plated
$11.56

Colony #9700-1 Transmission Filler Plug 1936-Up Harley-Davidson Big Twin - Parkerized
3 reviews $13.20

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

Colony #9678-2 Generator Screws 1930-1948 Harley-Davidson Big Twin Sidevalve - Parkerized
$10.37

Colony #9601-10 Inner Primary Cover Rear Bolt Kit 1936-1964 Harley-Davidson Big Twin - Parkerized
3 reviews $12.45

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

Colony #9684-10 Circuit Breaker & Relay Screw Kit 1936-1984 Harley-Davidson OHV Twins - Parkerized
1 review $10.04

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

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 #9656-8 Transmission Top Cover Screw Kit 1979-1985 Harley-Davidson Big Twin - Chrome Plated
1 review $8.78

Colony #9529-12 Pushrod Cover O-Ring Seal Kit Harley-Davidson Big Twin Evo/Twin Cam/Sportster
3 reviews $8.78

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

Colony #9803-4 Triple Tree Pinch Bolts Kit Harley-Davidson FL and Wideglide - Chrome Plated
$8.36

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 #9679-2 Generator Screw Kit 1936-1957 Harley-Davidson Big Twins - Parkerized
1 review $7.17

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

Colony #9016-3 Dash Mounting Kit Button Allen Head 1986-Up Harley-Davidson FXR (Except 88-Up FXRS) - Chrome Plated
$6.78

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

Colony #9734-7 Foot Brake Lever & Bracket Mounting Kit 1936-1971 Harley-Davidson Big Twin - Parkerized
2 reviews $6.38

Colony #9733-7 Foot Brake Lever & Bracket Mounting Kit CAD Harley-Davidson 1936-71 - CAD Plated
2 reviews $6.38

Colony #9691-2 Seat Post Rod Lock Nut & Washer 1925-1981 Harley-Davidson All Models (Except FX/XL) - Parkerized
6 reviews $9.35

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

Colony #9758-2 Fork Slider Drain Screws Button Head Allen 1977-1984 Harley-Davidson FL 1977-1984 FXWG/FLT 1980-Up Softail - Chrome Plated
5 reviews $5.95

Colony #9717-1 Starter Crank Pin Stud 1936-Up Harley-Davidson Big Twin - Parkerized
$5.18

Colony #9404-1 Oversize Harley-Davidson Timing & Oil Tank Plug - CAD Plated
1 review $8.80

Colony #9821-4 Oil Filter Adaptor Mounting Allen Kit 1992-Up Harley-Davidson Big Twin - Chrome Plated
1 review $4.76

Colony #9675-1 Motor Case Drain Plug 1911-1970 Harley-Davidson 1968-1984 Oil Pump Body - Parkerized
1 review $5.50

Colony #8220-20 Head Bolt Kit 1940-1947 Harley-Davidson Knucklehead - Chrome Plated
1 review $76.76

Colony #8219-20 Head Bolt Kit 1936-1939 Harley-Davidson Knucklehead - Chrome Plated
1 review $76.76

Colony #8218-36 Head Bolt Kit 1940-Up Harley-Davidson 1930-1947 Flathead 74 & 80 Iron Heads - Chrome Plated
$123.48

Colony #8136-34 Motor Case Kit Acorn Head 1965-1969 Harley-Davidson Big Twin - Chrome Plated
1 review $63.61

Colony #8139-34 Motor Case Kit Acorn Head 1970-1978 Harley-Davidson Shovelhead - Chrome Plated
$63.61

Colony #8129-34 Motor Case Kit Stock 1936-1939 Harley-Davidson Knucklehead - CAD Plated
1 review $51.70

Colony #8144-34 Motor Case Kit Stock 1979-1995 Harley-Davidson Shovelhead/Evo - CAD Plated
$51.70

Colony #8141-34 Motor Case Kit Stock 1970-1978 Harley-Davidson Shovelhead - CAD Plated
$51.70

Colony #8135-34 Motor Case Kit Stock 1948-1964 Harley-Davidson Panhead - CAD Plated
2 reviews $51.70

Colony #8132-34 Motor Case Kit Stock 1940-1947 Harley-Davidson Knucklehead - CAD Plated
$51.70

Colony #8602-20 Oversize Stroker Upper Pushrod Cover Kit 1940-1947 Harley-Davidson Knucklehead & All Shovelhead - Chrome Plated
1 review $50.08

Colony #8734-24 Valve Cover Screws 45/64 inch Long 1954-1965 Harley-Davidson Panhead With Steel D-Rings - Chrome Plated
$41.97

Colony #8732-24 Valve Cover Screws 1-1/4 inch Long 1954-1965 Harley-Davidson Panhead With Alloy D-Rings - Chrome Plated
1 review $41.97

Colony #8143-34 Motor Case Kit Stock 1979-1995 Harley-Davidson Shovelhead/Evo - Chrome Plated
$58.30

Colony #8140-34 Motor Case Kit Stock 1970-1978 Harley-Davidson Shovelhead - Chrome Plated
2 reviews $58.30

Colony #8137-34 Motor Case Kit Stock 1965-1969 Harley-Davidson Big Twin - Chrome Plated
2 reviews $58.30

Colony #8134-34 Motor Case Kit Stock 1948-1964 Harley-Davidson Panhead - Chrome Plated
3 reviews $58.30

Colony #8131-34 Motor Case Kit Stock 1940-1947 Harley-Davidson Knucklehead - Chrome Plated
$58.30

Colony #8724-18 Handlebar Clamp & Gauge Acorn Head Mount Kit 1983-1994 Harley-Davidson FX/XL - Chrome Plated
$20.27

Colony #8413-8 Handlebar Switch Housing Acorn Head Screw Kit 1973-1981 Harley-Davidson Big Twin & Sportster 73-81 - Chrome Plated
$20.27

Colony #8774-18 Footboard Hinge Bolt Buddy Footrest Kit 1941-1964 Harley-Davidson - CAD Plated
$25.00

Colony #8758-10 Disc Brake Rotor to Hub Screw Kit 1978-1982 Harley-Davidson FX/XL - Chrome Plated
3 reviews $21.97

Colony #8745-13 Oil Pump Mounting Kit 1936-1967 Harley-Davidson OHV Big Twins - Chrome Plated
$20.31

Colony #8756-30 Primary Cover Allen Screw Kit 1936-1984 Harley-Davidson Big Twin - Chrome Plated
$30.00

Colony #8923-8 Handlebar Throttle Spark Roller & Pin Kit 1910-1948 Harley-Davidson All Models
1 review $25.00

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.

Read less

Harley-Davidson Big Twin Parts FAQ

STAY CONNECTED
WITH LOWBROW

NO SPAM, EVER. JUST GREAT STUFF. YOUR INFO IS NEVER SHARED.