I want to lay a little challenge out there for the "Entrepreneurs" in RC. .

Do these conversions for a living, be competitive in terms of # of units sold, weight, and power when compared to DA, BME, Taurus and Brison. Then, feed your family, pay taxes, and make an acceptable profit on your work, plus satisfy fickle customers who have little understanding of what you go through every day to satisfy their desires.

A few restrictions will, of course, apply. You are not allowed to trash the competition, you can't make any excuses if your product is not quite as "Good" as the perceived competitions, and when someone runs lean/prop strikes/overheats/crashes the motor you must be understanding and nice about it and not charge them an arm and a leg for repairs. And, most importantly, you must answer the phone and do a lot of problem solving and ego-soothing to irate or upset customers on a daily basis.

Nothing against BN120 and his 56 cc motor. It's light, makes okay power, and is cheap (for him) to do this one time. Add in about $15/hour for the time he spent making parts and re-machining the motor for a "real world" cost, though, then try to put 200/month out the door, and you will quickly see why "Manufacturers" charge a bit of money so they can make ends meet.

As for who does or does not know what they are talking about? (or is/is not an "expert") that is open to debate. A lot of people on these forums can read from a book or make claims (yup, even me, if I was so inclined) that do not really address the reality of what is required for our model engines (Lightweight first of all, power secondary, and tractability tertiary considerations) to me a marketable and sell-able commodity. In the real world (the nose of a model plane) throwing the advantages of water-cooled motorcycle/Kart engines into the mix will not work, because of the tremendous performance improvements inherent with water cooling (leaning of mixture, steady temperatures, more radical porting, more BMEP). IF we wanted to go to 15-18 lbs water cooled motors that required radiators and support equipment, and thus weigh our planes down, there would be an alternative int hat direction. But, since air-cooled motors are the only way to get the weight and complexity down to manageable levels, there probably is not going to be a shift into the water cooled direction. So, we can kiss Kart/motorcycle motor technology goodbye. We can also kiss 10-12,000 rpm power bands and huge tuned pipes goodbye too. . one from the propeller perspective, and the other from weight and packaging considerations. People who "know" realize this, and laugh a bit when someone brings up the idea for the umpteenth time. Personally I really don't want a radiator, hoses, water, heavy motor and 3 foot tuned pipe in my plane, no matter how much power it makes on the top end. It's just not practical.

This thread is "Lightest 56cc", which infers, especially considering other claims made in other threads, that not only would the motor weigh less than a current BME/DA/Taurus/Brison 50cc sized motor, it would also make more power. At 12-13% larger displacement, this seems to be a not unrealistic expectation. True, the motor is inexpensive, for a one of a kind. . production models would be a LOT more expensive. True, it's lighter by a few ounces than the motors its compared to. But no, it's not as powerful given established performance numbers from the "big 4" in the 50cc category. And then, it's not marketable to the general public since no one is going to make it available.

In baseball parlance, I call that two balls, two strikes. If the power had been better, or even just on par, I'd say it was a home run (people are going to start throwing numbers around again. . . .) sure, its a lightweight, inexpensive motor. . probably will power a plane pretty well. Make more and sell them, and lets see it on the open market and then things might get exciting in the 50-60 cc motor class in RC. I'd really like to see how far it went, because the more LIGHTER powerplants we have out there, the better for US as consumers, and the more receptive kit/arf makers will be to redesigning their planes to reflect evolution in this direction.

BN120. . congrats on your effort. . It's not a DA or other mass-marketed engine, but I'm sure it will fly your plane just fine. I BET you could take a 50cc Echo and beat BME at it's own game, if you wanted to. Might be a direction to look at. Personally, I was VERY disappointed (read that PO'd)that the 56cc did not beat the #s of a DA50 (be realistic here, now). The 3w/DA 100's have been a performance target for quite a while. . I really like matching their rpm figures with my lowly BME's on pipes, then beating them on total weight. . .it kind of shows the direction this hobby should be going, and YOUR effort shows what the average person, with a little work, can accomplish. Unfortunately, a LOT of us just don't have the time, so we reach into our pockets to buy what we perceive as the best value for our hard-earned cash. Unfortunately. . that results in "the herd" thinking that a $500+ 50 or $1150 100 is acceptable. It's not, but it's also what we are stuck with.