Concord, Ohio based manufacturer Cometic Gasket has released new stock replacement and big bore gasket and cam change gasket kits for Harley’s M-8 touring engines.
Because there are currently two very different cylinder head designs offered on the M-8, Cometic is releasing a number of different gasket designs.
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| Left pair: C10169 - MLS 4.200” bore head gasket .040” for oil and coolant cooled headsRight pair: C10177 - single layer steel base gasket stock bore to 4.250”, .014” thick |
One version of the M-8, the one used in Touring models with no lower fairings, features oil cooled heads. A second M-8 cylinder head version, this one found in Touring bikes with lower fairings and with radiators behind them, has provisions for that coolant to flow through the heads, and Cometic say they have gaskets for both, in sizes ranging from the stock 107 and 114 cubic inch displacements to a big 4.500 inch big bore size.
All told, there are nine different cylinder head gaskets in this M-8 line-up, along with new base gaskets and the full cam change kit. Sales Director Jason Moses told AMD: “While the differences between all those gaskets are small and subtle, they’re critically important.
“The oil cooled heads, the ones on bikes without lower fairings, have one “teardrop” shaped port close to the bore, and that is surrounded with an embossed surface. With this head design the M-8 big bore is limited to 4.200 inches with no modifications to the heads. Any larger than that would require the oil port to be welded shut and the head resurfaced.
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| C10178 - cam change kit, all M-8 Models |
“Our gasket for these oil cooled heads, the ones with the teardrop shaped port and embossed ring around it, will work on both oil cooled and coolant cooled heads with stock to a 4.200 inch bore with no head surface modifications.
“The second M-8 head design, the one used on bikes with lower fairings, radiators and coolant, has two round coolant ports set significantly further back from the bore than the oil cooling port. With this design, the big bore can safely go all the way to 4.500 inches with no coolant port modifications, and Cometic has gaskets in those bigger 4.250, 4.320 and 4.500 sizes.”
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| C9247 - race style exhaust gasket, .240” thick, all M-8 Models |
Cometic manufactures its gaskets from a comprehensive range of materials, including MLS (Multi-Layer Steel) gaskets or a synthetic blend such as aramid fiber.
“The M-8 is primed for modification,” continued Jason. “Gaskets are a staple for servicing and a vital component for reliability and performance. The two different head styles are catching many builders by surprise, and by being first to market with service replacement and big bore solutions, we think we are going to be making the lives of a lot of workshops a lot easier and the engines of a lot of riders a lot more reliable.”
COMETIC GASKET INC.
www.cometic.com