Almost identical to OEM. Good fit. I did miss that they are sold as each and not as a pair. Small detail and my fault but it did slow my project down a bit.
Cometic M8 Molded Rubber Primary Housing Gasket - Harley Milwaukee-Eight
About Cometic
Cometic Gasket manufactures multi-layer steel head gaskets and complete gasket kits in Concord, Ohio. On a built V-twin running higher compression or a big-bore kit, the MLS head gasket is what keeps the top end sealed — which is why Cometic is the default spec on so many engine builds.
When servicing your Milwaukee-Eight primary, a reliable gasket is non-negotiable for preventing leaks and ensuring proper function. This Cometic molded rubber primary housing gasket is engineered as a direct replacement, offering a robust seal for your Harley. It's built to OEM specifications, providing confidence in its fitment and performance.
Why riders pick this
- Molded rubber construction for superior sealing
- OEM-spec replacement for Milwaukee-Eight engines
- Direct fit to the primary housing
- Designed to prevent primary oil leaks
The Cometic molded rubber primary housing gasket is a high-quality replacement designed specifically for Harley-Davidson Milwaukee-Eight (M8) engines. Its molded rubber construction provides a superior and more durable seal compared to standard paper gaskets, effectively preventing oil leaks from your primary cover. This gasket is a direct-fit component, making installation straightforward for riders performing their own maintenance or upgrades.
Enhanced Sealing for M8 Primaries
- Molded rubber construction for improved durability and seal integrity
- Direct replacement built to OEM specifications for M8 engines
- Ensures a precise fit to the primary housing
- Helps prevent oil leaks from the primary cover
Reliable for Maintenance and Upgrades
Whether you're swapping clutches, inspecting your primary drive, or simply replacing a worn-out gasket, this Cometic primary housing gasket delivers the performance and reliability you expect. It's an essential part for any Milwaukee-Eight owner looking to maintain their bike's integrity and avoid messy oil leaks. Trust Cometic for components that stand up to the demands of your V-twin.
Specifications
- Brand: Cometic
- Manufacturer Part #: C10306F5
- Length: 7 in
- Width: 6 in
- Height: 0.05 in
- Weight: 1 lbs
Common questions
Is this primary gasket compatible with Twin Cam engines?
No, this Cometic gasket is specifically designed for Milwaukee-Eight (M8) engines. Twin Cam models require a different part number and gasket design.
Is this an OEM Harley-Davidson gasket?
This is a Cometic-manufactured replacement gasket that is built to meet or exceed OEM specifications for Harley-Davidson part #257010, ensuring factory-level fitment and sealing performance.
What tools are needed to install this gasket?
Standard hand tools for primary cover removal, along with a gasket scraper for surface preparation, are typically sufficient for installing this primary housing gasket. No specialized tools are required.
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 | Cometic |
| TYPE | Gaskets/Seals |
| SKU | 68-10306F5 |
| WEIGHT | 1.0 lb |
Great seals and gaskets do the job once when you use quality gaskets
Seal good and I haven't had any issues..
It worked like it was suppose to, delivery was quick. <br />Pleased.
Just what I needed
Needed these when changing out intake manifold. They worked perfect for my ‘03 sporty.
Cometic from here on out
These seals are the only ones I'll use. others came close but, for me, these are best.