✓ VERIFIED
Jul 15, 2024
Great product and always fast shipping
JAMES GASKETS
SKU: 681-4392
James Gaskets Cylinder Head & Base Gasket Kit 3 5/8 Bore - Harley Big Twin
$51.95
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About James Gaskets
James Gaskets has supplied American V-twin gaskets, seals and O-rings for decades and is one of the most widely stocked names for Harley-Davidson engine, primary and transmission rebuilds. When a service manual calls for a specific gasket, James almost always has an exact-fit answer.
This James Gaskets Big Twin gasket kit is specifically designed for 3 5/8-inch bore cylinders, providing the essential cylinder head and base gaskets needed for top-end rebuilds or base gasket replacements. It offers a direct replacement for standard Big Twin V-twin engines.
Why riders pick this
- Cylinder head and base gaskets included
- Designed for 3 5/8-inch bore cylinders
- Direct replacement for Big Twin V-twins
- Essential for top-end rebuilds
- Ensures critical engine sealing
When working on the top end of your Harley Big Twin, precision and proper sealing are non-negotiable. This James Gaskets kit delivers both, with gaskets specifically sized for 3 5/8-inch bore cylinders. The kit includes both cylinder head and base gaskets, ensuring a comprehensive seal for critical engine interfaces. These are direct replacement components, designed to meet the demands of your V-twin.
Precise Sealing for 3 5/8 Inch Bore
- Includes cylinder head gaskets for a secure seal
- Provides base gaskets for the cylinder-to-crankcase interface
- Specifically for 3 5/8-inch bore cylinders
- Direct replacement for Big Twin V-twin engines
Crucial for Top-End Integrity
Maintaining the integrity of your engine's top end is vital for performance and preventing leaks. This James Gaskets kit provides the core seals required for a successful rebuild or service on your 3 5/8-inch bore Big Twin. Always verify your engine's bore size before purchasing to ensure perfect compatibility and a reliable seal.
Specifications
- Brand: James Gaskets
- Manufacturer Part #: 16770-86-S
- Weight: 0.156 lbs
Common questions
What gaskets are included in this kit?
This kit includes cylinder head and base gaskets – the two most critical seals needed for a top-end rebuild or base service on 3 5/8-inch bore cylinders.
Will this fit my engine if I don't know the bore size?
This kit is specifically for 3 5/8-inch bore cylinders. It is crucial to check your engine manual or existing gasket packaging to confirm your bore size before ordering to ensure correct fitment.
Do I need any other gaskets for a complete rebuild?
This kit covers the head and base. Additional gaskets like rocker cover, oil pump, or cam cover may be needed depending on the full scope of your rebuild. Always consult your service manual.
Ordering from Vtwinbikers
- Brand new, sourced through authorized US distribution — never used, never grey-market.
- Not sure it fits? Use Shop by Bike to filter by your year and model, or email us and we will confirm before you order.
- Harley-Davidson and Indian Motorcycle is all we do, so you are talking to people who ride what you ride.
| BRAND | James Gaskets |
| TYPE | Gaskets/Seals |
| SKU | 681-4392 |
| WEIGHT | 0.16 lb |
Please contact us to confirm fitment for your specific motorcycle, or check the product title for compatibility notes.
CUSTOMER REVIEWS
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✓ VERIFIED
Oct 20, 2021
Works as it should, would buy again.
✓ VERIFIED
Jun 16, 2021
They're gaskets.
✓ VERIFIED
Mar 2, 2021
Perfect fit, on time delivery all is well.
✓ VERIFIED
Jul 30, 2020
I only need one head gasket so I had to pay for a set which I have no use for
✓ VERIFIED
Jun 5, 2020
Great gaskets. Won’t use anything else.
