✓ VERIFIED
May 16, 2026
not what I needed. description wasn't very clear but not worth sending back. oh well just have to be more careful next time
COMETIC
SKU: 68-9851
Cometic Evo Big Twin EST Gasket Kit - Harley Evolution Big Twin
$140.45
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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 rebuilding your Evolution Big Twin engine, the Cometic EST Gasket Kit provides all the critical sealing components you need for a complete and reliable overhaul. This kit is designed to meet the demands of your V-twin, ensuring a tight seal for optimal performance.
Why riders pick this
- Complete engine overhaul gasket kit
- MLS head gaskets for secure sealing
- Steel Viton-coated base gaskets
- Blue Viton valve stem seals
- AFM material components included
A successful engine rebuild hinges on the quality of its sealing components. The Cometic Evo Big Twin EST Gasket Kit offers a comprehensive solution, supplying every gasket, seal, washer, and O-ring for a full engine overhaul. Featuring Cometic's Extreme Sealing Technology, this kit includes advanced materials like MLS head gaskets and Viton-coated base gaskets, engineered for superior durability and leak prevention in high-stress V-twin environments.
Engineered for Lasting Performance
- Includes MLS (Multi-Layer Steel) head gaskets for robust sealing
- Features steel Viton-coated base gaskets for heat and chemical resistance
- Equipped with blue Viton valve stem seals for enhanced longevity
- AFM material components ensure comprehensive sealing
- Complete overhaul kit with all necessary gaskets and seals
Confidence in Every Seal
Investing in a Cometic EST Gasket Kit for your Evolution Big Twin means you're choosing reliability. The precision-engineered components help maintain proper compression and prevent fluid leaks, critical for both stock and modified engines. Whether you're refreshing an older motor or completing a full rebuild, this kit delivers the quality and performance you expect from a leading gasket manufacturer.
Specifications
- Brand: Cometic
- Manufacturer Part #: C9851
- Length: 9 in
- Width: 7.5 in
- Height: 2.1 in
- Weight: 0.755 lbs
Common questions
Will this gasket kit fit all Evolution Big Twin engines?
This Cometic EST Gasket Kit is designed for Evo Big Twin engines. We recommend verifying your engine code and specific model year with our Shop by Bike tool to ensure perfect compatibility.
What is the benefit of MLS head gaskets?
MLS (Multi-Layer Steel) head gaskets offer superior sealing capabilities compared to traditional composite gaskets, providing better heat dissipation and resistance to blowouts, especially in high-performance engines.
Are all necessary gaskets and seals included for a complete engine overhaul?
Yes, this Cometic Evo Big Twin EST Gasket Kit is a complete overhaul kit, supplying every gasket, seal, washer, and O-ring needed for a full engine rebuild.
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 | 68-9851 |
| WEIGHT | 0.75 lb |
Please contact us to confirm fitment for your specific motorcycle, or check the product title for compatibility notes.
CUSTOMER REVIEWS
4.36
14 RATINGS
5★
11
4★
0
3★
1
2★
1
1★
1
✓ VERIFIED
Mar 8, 2026
Gasket
Working fine was for my brother's bike
✓ VERIFIED
Oct 25, 2024
Works Fine at a lower cost
I usually have an OEM from Harley Davidson, I have used this twice on my 04 Electraglide, no leaks or issues. At a much lower price.
✓ VERIFIED
Jun 8, 2024
A mediocre gasket
I didn’t use this gasket after removing the derby and seeing the Harley gasket that I removed. No comparison in quality. I ended up going to the local dealer and bought an O.E. gasket.
✓ VERIFIED
Jun 6, 2023
A good buy
The gasket fit nicely and no leaks so far . The fitment was spot on .
✓ VERIFIED
May 4, 2023
There is nothing on them indicating they are actually Cometic gaskets. Are they Substitutes?
