The Japanese plants likely could not meet production goals or, more likely, cost objectives. Don't be surprised to see Made in China on the parts packaging. Even Daimler has a Mercedes plant there. As long as the quality is maintained to original standards it shouldn't be a problem

To the best of my knowledge the GX has never been made in the US, although US assembled high-end and commercial mowers do incorporate the GX.

The worst part about this is the camshaft gear is made of plastic. A highly critical part of the engine and they made it out of plastic?

Why do you care or worry where it is built

"As long as the quality is maintained to original standards it shouldn't be a problem"

This is a subject that comes up in all kinds of things including cars. The bottom line is that although they may be manufacturing in other countries what really matters is the manufacturing specs and procedures. As long as the company keeps to the specs it doesn't matter where their equipment is made.
There are US autos that are manufactured in Korea.
Bottom line is, as long as it works they way it is supposed to do that is what counts.

Here is a link that might be useful: Irrigation Eqiupment

As I said, the important thing is that it runs well. I was just surprised that their "higher end" engines were built there. I just figured those still came from Japan. As for the camshaft gear, I think just about all of the engine manufacturers have gone that route - at least with the smaller engines. Again, as long as it works, I guess its nothing to worry about. I wouldn't think Honda would risk their reputation with any parts that might fail.

"The worst part about this is the camshaft gear is made of plastic. A highly critical part of the engine and they made it out of plastic?"

The term "plastic" conjures up images of vending machine toys that snap when bent slightly. The composite products used in camshafts, automobile suspension springs and the like are made from materials that are designed for the task. In a lawn mower engine I can see where a composite camshaft would reduce noise from the valve train. My Toro Super Recycler has a Briggs 6.5hp engine with a composite cam is 5 years old and runs like a champ. I have not read of any reports of camshafts or other high stress components made of composite materials failing at a rate any different than those made of steel.

"I wouldn't think Honda would risk their reputation with any parts that might fail."

No one is really concerned with their "reputation" anymore. Manufacturers are just like life insurance companies.

Life inurance companies have actuaries who figure out what percentage of people will die young, what percentage will live beyond their normal life expectancy and then price their policies accordingly.

Manufacturers do the same thing. Like life insurance companies as long as their calculations are correct and too high a percentage of their products do not die too young, they will be sucessful.

You are describing manufacturing in the 21st century. Does it matter that something you expected to be manufactured in Japan was actually manufactured in Thailand? Well, yeah, it might. A person who came to the USA from southeast asia, in the late 1970's might be more inclined to buy a product made there, as opposed to Japan. Someone born in the USA before 1930, who remembers Pearl Harbor, might be more comfortable with a product from Thailand than one from Japan. Most of us are more likely to associate goods made in Japan with high quality and reliability, because of the reputation the Japanese made back in the 1960's with cameras, electronics, and cars. As for me, I can't help but wonder what the people who work in the Thailand factory are paid, and how they are treated by the company. I'm not real excited about plastic camshaft gears, either.

What a joke some of these comments are doesn't matter where it's made Ask that same question 25 years from now Using Honda equipment all my life I rarely see aan orginal Honda engine in the scrap bin like I see the GX engines are