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Gaskets and Seals› Engine Gaskets and Seals
Cometic Gasket
Cometic 1984+ Harley-Davidson Stock Big Twin .020 Copper Base Gasket - 2 Pack
SKU: C006 C9817
Easy — 1–2 hours
Overview
Show original supplier description
Part #: C9817
For todays hi-horsepower bikes
Vehicle Symptoms
- Oil leaking from cylinder base onto engine cases
- Engine misfire or rough idle due to compression loss
- Visible oil seepage around base gasket area
- Decreased engine performance or power loss
- Excessive engine noise from cylinder area
Relevant Conversations
- Harley base gasket oil leak fix
- Cometic copper base gasket vs OEM
- 1984+ Harley Big Twin base gasket replacement
- How to install Cometic base gasket .020
- Oil leaking from cylinder base Harley Davidson
- Best base gasket for high compression Harley
- Copper base gasket 2-pack C9817 review
- Harley engine rebuild base gasket torque specs
- Symptoms of blown base gasket Harley
- Cometic C9817 fitment for 1999 Road King
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | Cometic Gasket |
| Part Number | C006 C9817 |
Videos
Cometic Gaskets presented by J&P Cycles.
Harley-Davidson MLS Head gaskets | Torque Values | Doc Harley
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REMOVE Harley Head Gaskets FAST! & EASY!
Unveiling Jamie's Exhaust Gasket Secrets
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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