To be clear, and admire, a person's desire and ability to design an engine and then make a small business out of supplying either plans or kits. It is that transition from hobby to business, and more than one large entity has come from that. I doubt any significant business will come about from model motors, but it doesn't really matter. In the end, it can just be hobby income and it is still a protected right.
I also applaud you greentwin (and others) for making your plans public if you have no intention of marketing them. I guess there are really only two choices. Knowing that China is devoid of business ethics, when you release a set of plans publicly you do so with the knowledge that you very well could see commercialization from China of your work. Frankly, even if you *sell* the plans/kits, as Todd has eluded to with his eBay sales restrictions, you run that risk. The other choice is that you keep everything you've ever done close to the chest and never let anyone know about it. Honestly, I think we all benefit from one another, and I hope that the choice is to release things when you are "done with them." Stipulate it in your will, if you want, so that your heirs will know. We will all thank you for the contribution. And, we will put to rest the extensive comments about the copyright conundrum.
Steve/Todd... I hope you haven't interpreted my comments as condoning illicit copying of your plans as you are actively marketing them. And, yes, legally you have the right to restrict even after you cease marketing them. I just hope that you'll not go down that route unless you are selling the businesses to someone else that will sell them, etc. I *am* in your corner, and I have long looked at both your products. I come close to pulling the trigger frequently, but haven't done so yet. I will eventually....
Back to you GreenTwin... Yes, it can be fun to see morphing of something after it has been released. In the software world one need only look at Linux as a prime example of what *can* happen in the public domain. We all benefit from Torvald's actions, and I *know* Linux has progressed far far beyond what he originally had. If I were he, I'd be thrilled to see what it has become. And if you don't think we have benefited from his actions, consider this... There is a *very* good chance that the servers being used to host HMEM are running Linux.
On edit: (posted while Steve was adding his own comments).... yes, I think I shall stop too. it really is a disservice to the original poster to have hijacked his thread. To him, I extend my apologies.... I also extend a suggestion... It is great that you are enamored with how the engine works. You are learning something and that is what life is about.... I would like to encourage you to consider getting a set of plans and try your hand building something. You may fall in love with the hobby. There are a myriad of books, free plans, or paid content such as by some of the vendors that have posted even in this thread. All are wonderful resources. So.... Join on in! We welcome all new members to the hobby!