The Cometic C3747 is a top-end engine gasket kit used in powersports engines—specifically designed for certain Sherco 250 SEF-R four-stroke dirt bikes.

Basic Identification
Manufacturer: Cometic Gasket
Part Number: C3747
Type: Top-end gasket kit
Bore Size: 78 mm
Category: Powersports engine gasket kit (for top-end rebuilds)

Sherco
2021 - 250 SEF-R Racing
2020 - 250 SEF-R Racing
2019 - 250 SEF-R Racing

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