Tracks blades: Sorry for the confusion. I had all the decking on the cylinders and just the minimum to clean up the head mating surface. This to get get top of piston at top of cylinder. Original o-ring recess re-counter bored to original depth. When I mocked up top end I noticed o ring hole in MLS gasket too small to clear OD of Honda OEM o-rings. Then checked with my machine shop to see if MLS embossed hole perimeters would provide proper seal. They said that they would seal without the o-rings, just the head gasket with these sealing rings. Do you have information that this is not adequate? If so I would like to hear. I am not trying to mislead or confuse anyone here just trying to share my experience.
Sano,
No apologies required. However, just to be clear, I'm not confused at all. I read all of your posts and comprehended them as you wrote them. Additionally I have long understood the definition of 50/50, .024 and .042 barrel (cylinder) machine cuts and how they differ. It is not clear why your posts are in conflict with one another...
Perhaps as I stated, it is difficult to know or correctly assume the aptitude of those posting. But, as one reads an individual's posts, one can recognize incremental progressive patterns of (increased or decreased) understanding of the selected topic. I'm sure if you reread all your own posts at once, over the entire 5 month time frame as I did, you may recognize the same as well as an emerging confidence.
It is interesting to note the same Head Spinning post referencing SAE machining standards, and in particularly FKM and FPM orings' advanced material commonly known as Viton (registered trademark of DuPont now Chemours Co), is the same material your selected MLS head gasket is coated with. Requiring similar surface finishes as the Viton orings.
In your post you made a .030 crush recommendation and a .040 crush recommendation as even better. The information within the Parker/Hannifin oring handbook covers the correct accepted ASE machining standard for each thickness of oring to achieve the desired compression with respect to the selected durometer.
In essence the Oring wheel has already been invented. Ask any current machinist. DuPont originally offered Viton trademark Orings in 1960 or shortly thereafter. It's interesting to note, 75 durometer Viton orings are black in color and are rated from -40 to 400f. The airplane and vw mechanics on here can tell you what temperature an average aircooled cylinderhead can reach, as well as the soak down temperatures. Without any review at all to the Oring post, you should understand now it's the material that determines the temperature rating not necessarily the color. For instance, temperature ratings for black orings range from 210f to +400f depending on materials. Can you tell one from the other? Me either, without testing. And at $7.00 per 30 pack for small Viton sizes, why test when you can be sure.
Finally, in reference to your MLS head gasket embossments interfering with the original Honda Oring's outside diameter, I would ask you just the opposite. Does the Honda Oring counterbore interfere with the embossments on your head gasket?
As far as inadequacies, you may be the guinea pig here. I've only read of the builders here using the orings in addition to. I too enjoy this forum's members active participation and contributions.
Honda enjoyed quite a success with their original design selections for the CB550 40+ years ago.
How many miles do you have on it now, after your rebuild?
