RCMK & CY & Zenoah motors

[CyberVet65]

I know RCMK is RC Marine Korea. And I know RCMK has been into marine engines since about 2006. And I know the CY motors are better quality than the HY motors. And top of the line and usually most expensive is the Zenoah engines.
My questions are:
Is the CY and the RCMK Asian clones of the Zenoah?
Are the parts interchangeable between the HY and RCMK and the Zenoah?
RCMK appears to be marketed by King Motors. Are parts available?
Would a 4 bolt head on a RCMK work on a 4 bolt Zenoah?
Are the modified RCMK reliable?
Will they stand up to the extra wear and tear on a modified engine?

 

[Revolauncher]

That is going to take a lot of experience to answer all those questions, whew. Many parts are interchangeable with all 3 brand engines within their specific displacements: 23cc, 26cc, 29cc, & 30cc, etc. but there are subtle variations also in crankcase, bolt patterns, head porting, and timing. I have found that almost everyone's 26cc fuelie has crossover parts and compatibility with other 2 bolt engines, but 4 bolt crankcases start to get quite unique with stroker cranks, heads stack height just for starters, and such.....I do not know of a spreadsheet out there that has a part number listing to cross reference, that would take quite some time to put together, I imagine. This thread might be a good place to start if you have the title changed. People could just post what they have used from other brands that fits. All I know is ebay is a frustrating place to sell engine parts, as a seller my parts go out new and get returned to me thrashed from improper assembly or fit and my perfect feedback held hostage.

 

[46u]

The air cooled RCMK engines like the CR300F have a very different ports then CY and Zenoah.

 

[46u]

Just received my RCMK 300F Saturday and I am very impressed with how it is made. Will know more once I finish installing it and get it broke in. CY have two crank bearings, Zenoah has 3 and the RCMK has 4. CY and Zenoah has a 4 port transfer ports and RCMK has 6. I have talked to quite a few who own the RCMK and all say they will never go back to running anything else. I will post more later.