Looking for a .050 Thick x 4.00 bore Cometic MLS head gasket.
They make them to order anyway. Give them a call.
Quote from: spdrcr on January 08, 2019, 02:55:00 PM
Looking for a .050 Thick x 4.00 bore Cometic MLS head gasket.
I bet your local indi can get them. Where have you looked?
I looked on the Cosmetic site. It's the most user friendly. I didn't see a .050 thick 4.00 bore.
Call them. They will build to your spec if they have the material at no extra fee. Can't beat that.
They have alot of gaskets that are not listed and i know they make .051 in most cyl dimensions
Thickest 4" we stock is .040".
If you are adjusting for positive deck height, another option is to use the standard .030" head gasket, and then a .020" base gasket.
https://www.cometic.com/c-1289531-v-twin-cruiser-base-gaskets.html
Quote from: rigidthumper on January 10, 2019, 05:42:54 AM
If you are adjusting for positive deck height, another option is to use the standard .030" head gasket, and then a .020" base gasket.
https://www.cometic.com/c-1289531-v-twin-cruiser-base-gaskets.html
:agree: Adjusting from below with a base gasket is doable even if you have to make / modify the standard size. It would also work for adjusting compression. This way you get to keep the desirable .030 quench dimension too. Myself and at least one other member here added a few thou to a base gasket. I used Vellum cotton paper (https://en.wikipedia.org/wiki/Vellum) and used an aviation sealant like Yamabond to seal them together. This type of adhesive does not add to the stack and seals the base up very nicely.
Cometic will cut about anything in a gasket for a reasonable price. My R1 had a big bore kit and would need a larger bore, .120" thick gasket. Cometic quoted a price that was less than the stock gasket from Yamaha.
Quote from: PoorUB on January 10, 2019, 08:04:01 AM
Cometic will cut about anything in a gasket for a reasonable price. My R1 had a big bore kit and would need a larger bore, .120" thick gasket. Cometic quoted a price that was less than the stock gasket from Yamaha.
:agree: I agree. My experience is that they need to have the right dimensions of material to assemble the gasket wafers. In some cases they may not be able to hit the exact dimension but will come close. Phoning them and discussing will open up more options than the catalogue. Speaking of the catalogue, they have a special edition called Performance Powersports - V Twin that is more specific than their regular offering. I have both and there is a more focused selection.
Quote from: kd on January 10, 2019, 06:49:40 AM
Quote from: rigidthumper on January 10, 2019, 05:42:54 AM
If you are adjusting for positive deck height, another option is to use the standard .030" head gasket, and then a .020" base gasket.
https://www.cometic.com/c-1289531-v-twin-cruiser-base-gaskets.html
:agree: Adjusting from below with a base gasket is doable even if you have to make / modify the standard size. It would also work for adjusting compression. This way you get to keep the desirable .030 quench dimension too. Myself and at least one other member here added a few thou to a base gasket. I used Vellum cotton paper (https://en.wikipedia.org/wiki/Vellum) and used an aviation sealant like Yamabond to seal them together. This type of adhesive does not add to the stack and seals the base up very nicely.
Adding material under the cylinder will increase the quench the same as a thicker head gasket. You are moving the head away from the crank centerline.
I am trying some different CC heads and want to adjust the CCP with the gasket.
Keep in mind, the farther the head from the piston, the more detonation-prone an engine can become.
My I ask why such a thick gasket?
If lowering for compression why not get different cam, would be easier. Just a thought.
I want to run an Andrews 48 cam on a 110 with 86cc stock heads, That have been DIY ported and polished.
Quote from: spdrcr on January 17, 2019, 05:10:01 AM
I want to run an Andrews 48 cam on a 110 with 86cc stock heads, That have been DIY ported and polished.
Did you unshroud or sink the valves while you were in there? Final CC numbers of the chambers? How far down the hole is the pistons? Flat tops or S&S +.75cc pistons? Shooting for #200 CCP? With a ~9.6:1 corrected CR, a good tune is necessary, but very doable.
Flat Top SE pistons .007 in the hole. It's the SE 110 bolt on kit. Yes around 200 ccp and 9.6