BME102Evo-Great Motor!!
 

Okay, EVERYONE (except the competition) is wanting to know when the BME Xtreme110 is gonna be available . . SOON!!!!!

But, here's a quick report/review on the 102Evo I just got going on my small FC330LX.

First off. . the motor IS 4.37 lbs (4 lbs, 6 ounces on my digital fish scale) with plugs and propwasher/nut. Add in ignition (5 ounces) and your choice of exhaust for the final weight. Compared to the 140's and 150's I have laying around, its a FEATHER!!!

Okay, typical BME stuff. . light, light, light. hows it run? I have a set of home-made headers for the BME (from when I used them on a few 5.8's), and a pair of Pefa canisters for a 3w100, so that's what I used for the exhaust system. Total weight of motor and exhaust, with ignition, is 6 lbs 6 ounces (motor and ignition: 4-11 lbs, canisters and headers-1-9 lbs) OR. . just a little bit less than a DA100 with standard mufflers. I got away with leaving the bottom end needle where it was at, but the top end needed about 5/8-3/4 turn more gas to compensate for the better scavenging of the canisters. The prop is an AM28-10 that has been re-balanced and is actually 27.75" tip-tip. The first run-up came after 15 minutes idling along and in the mid-range (using 50:1 Homelite oil and 89 octane gas) and the motor turned 5950-6000 rpm with the AM28-10. . . about what I wanted to see at that point.

Then I took the plane and flew it for 4 tanks of gas, about 45-50 minutes total flight time, and re-tested the motors power. Still rich (burbling slightly at everything but full throttle and taking about 5 seconds to clear its throat) and fully warmed up (right after it landed) the motor was swinging the 28-10 at 6250-6300 rpm. Even at this mixture setting the mid-range was smooth and predictable at all times with the most linear throttle curve possible, as good if not better than the DA150 I own.

As far as I am concerned the little BME needs about another 4 gallons of gas, and a bit of tweaking of the needles as well, before it will be making near it's full power. I "expect" to see 6500+ with the AM28-10 when all is said and done. Right now it rips the prop on level lines, and the vertical is VERY good (even if the plane is 27 lbs)so I guess it has enough power as it is. But, we all want MORE, and so, when the 110Xtreme comes out, the Evo is going on the shelf until I can find another plane for it. :)

Of note. . IMAC has a 95 dB limit this year. . 6300 rpm, 28" prop and canisters netted 92-94 dB at 25 feet, and you could NOT hear the plane in the air unless you were really pushing the power. In fact some kid with a small 50cc (well muffled) ATV was running up and down the parking lot 50 yards behind the flightline. . . I kept thinking THAT was my motor because it was louder than the plane!! and, of course, if anyone was flying a .40-sized trainer they drowned me out. . . :D

So. . the last gasp of the BME 102 Evo is a GOOD one. . Powerful, lightweight, smooth and QUIET. If I didn't know the Xtreme was coming, I'd be quite content with this motor.

BME102Evo-Great Motor!!
 

No we're really not! Sorry, but hey we are wanting something,......you to stop shamelessly pimping BME or any other engine line. By the way in your ode to joy there you skipped the part about the ridiculous freakin price Keith, and the rest of the big names want for their motors built out of chainsaw cylinders and reciprocating assemblies. Please do us all a favor and visit your local Motorcycle dealer and ask to look at a cylinder off a powervalve equipped motocross bike so you can see once and for all what kind of port arrangement it takes to really make power. Maybe if Keith spent more time worrying about increasing his B.M.E.P. numbers and less time worrying about his sales numbers BME engines might not be such a poor value.

BME102Evo-Great Motor!!
 

Well said!!!!!! It is OK to brag about an engine, but with the top gas engines, DA, BME, 3W etc. it becomes like Ford VS Chevy. They are all good. :D

BME102Evo-Great Motor!!
 

Hey now... I use BME and with great results. They are light, powerful and great running engines however you will pay for for them. The price has tons do deal with supply and demand. We demand them so we are willing to pay for it. How many BME engines you see in the for sale forums? When you do see one how long does it take before it's gone. Product speaks for itself and doesn't need people like myself trying to explain why they are so popular and expensive. Add in the fact that Keith is a great guy as well right there answering the phone and your question what more could one ask for... a great product and great support but if you feel the price is too much then go buy a Zenoah and float you boat that way.

FC 2.6 at 27#s??
 

What I really wanna know is how in the world the 33%FC ended up to 27#s.
I'm following reports about this extra for a while now and everyone says 25#s or less. Most of them if not all with DAs which as you report Kris, weigh more than your BME setup.
Can you give us a rundown of your equipment Kris? or an explanation of the additional weight? :confused:

Thanks.-

BME102Evo-Great Motor!!
 

Here's the link to the review I did of the buildup of the [plane:

http://www.rcuniverse.com/showthread...66&forumid=142

In it I detail a lot of the buildup, and the last posts explain the weight distribution and parts and pieces I used. You will see, from the review, that there is VERY little I did to increase weight, and that the max I could hope to remove from the plane is 5.5-6 ounces of servo/linkage setup and possibly go to lighter batteries.

Remember, those DA's aren't using pipes. . but another guy here locally did a FC330 with a DA100 and standard mufflers, AND used Powerflites and still came in over 27 lbs. . close to 288

BME102Evo-Great Motor!!
 

i would like to add. . .for our "motorcycle 2-stroke gurus" out there, and who want to lambast BME and other Model Aircraft Engine builders. . Motorcycles are NOT limited by the weight of the engine. .they are NOT limited to less than 7000 rpm powerbands. . they do NOT last 2000 hours of run time, and the motors DO cost as much, if not more, than ours.

the common 125cc dirt bike 2-stroke has a powerband WAYY up there. . over 10,000 rpm usually, whereas OUR motors are required to make TORQUE below 7000 rpm. the 125 is a SINGLE, which is an inherently more efficient package, it has RADICALLY different porting so that it can breath above 8000+ rpm and make gobs of power up there, it uses a HUGE tuned pipe usually, and it weighs HOW MUCH?????

The BME weighs less than 4.5 lbs. . with pipes its less than 6.5, and it makes all its power in the low rpm range, an area of power output where 2-strokes are notoriously ineffecient and lacking in power. Take one of your"motorcycle" 2-strokes, and make it work ONLY below 7000 rpm, and you will begin to see the problems in making power in that rpm range for a 2-stroke motor.

NOW. . I DARe you to put a 125cc Motorcycle engine on one of our planes. . . . .first you have to add a ton of tail weight. . then you have to fit that pipe somewhere. . THEN you have to find a way to gear-reduce the output shaft about 2;1, THEN you have to price the entire assembly under $1000. .

I'm sure by now the most diehard "motorcycles make more power" fanatic has seen the utter stupidity of this argument. It's not even close to an apples vs. oranges comparison. More like Watermelons and Radishes.

BME102Evo-Great Motor!!
 

Well I would love to have Yamaha build us a model airplane motor. I think the point that SuperJ was trying to make is that a chainsaw cylinder is not state of the art and better porting designs could be produced. That's why BME is trying to commercialize their own cylinder on the Extreme.

BME102Evo-Great Motor!!
 

And the new BME cylinder IS the "state of the art", or as best as a LOT of "2- stroke gurus" who design and race motorcycles for a living can make it. Keith went to the BEST motorcycle aftermarket designers and modifiers to help him with this cylinders design, and what they came up with can arguably be called the best compromise for a 2-stroke given the RPM constraints of our propellors and noise limitations, while at the same time maintaing decently smooth midrange and idle characteristics.

So. .you see. . the guys who KNOW designed the cylinders for the Xtreme. I really don't think Yamaha, Suzuki, Kawasaki or anyone else could do a much better job AND keep it as light as it is.

BME102Evo-Great Motor!!
 

Geez....Yamaha has only been building some of the fastest 2-stroke GP engines for around 40 years. They certainly aren't a bunch of chicken pluckers. Anyway, I hope BME got it right with the new cylinder design. Moves the bar up a notch. Now if they'd only put a 6-bolt hub on it......

BME102Evo-Great Motor!!
 

6-bolt hub is being "considered". . . . but then again. . maybe not. :)

BME102Evo-Great Motor!!
 

This discussion was about a 102 which is piston port chainsaw cylinders and pistons with the intakes blocked by pretty plates cobbled on to a reed crankcase. FYI the 80 and 125cc powervalve engines are making 75% of peak torque by 4500 rpm and substantial torque it is as the aircooled suzuki 80 engine makes 17hp at 7800 rpm with no expansion chamber, just a can muffler according to dyno tests commisioned by one of the karting federations. Yeah I'm sure Keith hired the best Doctoral fellows in two stroke design and research at $1000 a day plus $200/hr on the dyno just like the big boys do. The fact that you are making these wild assumptions is one thing but no matter how much you toned them down none of them can be substantiated because its a freakin vaporware engine.

BME102Evo-Great Motor!!
 

Gee, Super. . how rude. .

but I digress. .. Get a motor, put it on an airplane, and IMPRESS US!!!!

If You CAN that is. . otherwise, it's not worth the bandwidth you are taking up.

BME102Evo-Great Motor!!
 

Rude? Rude is going to describe the awakening BME is going to get when the first "10.5 HP" 110 makes a pull on my Stuska. I bet it makes no more than 6.5-7 corrected BHP just like a "9 HP" ZDZ100 did right before it scattered itself to the four winds.

BME102Evo-Great Motor!!
 

uh... I'm with SuperJ. While I really like the direction Keith is going, there aint no way in hades he could compete with the likes of Yamaha, Suzuki, Kawasaki, or Honda if they ever decided to jump in on the model airplane engine market. None of the current model aircraft 2 cycle gas engine manufacturers could even come close to what these giants could muster in terms of sheer experience and know how. Too bad the market is too small for them to jump in, some of the Kart engines are quite impressive - able to haul my 180lb chicken bucket through a 13 sec quarter mile at 100 mph, and never go over 7k rpm.... umm... and the "pipe" wasnt that large at all...

Oh, and SuperJ, the 110 aint vaporware, its going to happen, and it will be competetive with the DA 100, where the 102 wasnt, yet still be light and powerful enough to add quieting devices without sacrificing performance, probably saving 1 or 2 flying sites for large scale aircraft. While the price tag is still high for what you get, at least he didnt raise the bar like, oh, say, YS would with a new engine. I just wish Keith would jump into the 150cc class so he could get the recognition he deserves....

BME102Evo-Great Motor!!
 

SuperJ. . if you dislike these motors so much. . why are you even here? It's rather obvious you are bashing for the sake of bashing right now. How bout , since you are an "Engineer", explaining the difficulty of building an engine like the BME or Da or 3W in the first place? It would be a LOT more productive than slamming them because they are not from Yamaha. . . . . then, put some of that engineering expertise to good use and IMPROVE them, if you can. somehow I think you, or just about anyone else, would be hard pressed to do so.

BME102Evo-Great Motor!!
 

You know what I have no particluar beef with BME if Kris^ was a member of the DA cult blowing smoke about them instead I would have essentially the exact same thing to say. In fact up until this 10.5 hp 3 lb nonsense I have tended to feel that BME was somewhat less outlandish in his claims than some of the other guys. I am here because I love two stroke motors Kris^. I 've been racing, breaking, modifying, welding, porting, and spending money on them for years in karts, sleds, bikes, PWCs and outboards. I simply can't get enough of them so when I got back into flying RC a couple years ago when we didn't get any snow all winter I naturally gravitated towards gas giant scale stuff. What I saw horrifed me it was like time travel back to 1974 free air snowmobile land. I went to a few events and asked some guys about this or that strange engine design, most people had little to say. I asked some supposedly top notch engine guys about this engines time area or that engines port roof angles or this engines use of the antiquated bridged exhaust port design trying understand where all this nostalgia technology was coming from and got no where. After quite some time asking these questions and receiving answers that were either nonsense, half truths or damn lies it hit me I was a one eyed man in the land of the blind. As for my ability to improve on a BME design how could you not improve on the 102 cylinder? My twelve year old nephew, a kart racing fanatic, could sketch on napkin how to add a boost port and two more transfers snuggled right up against the sides of the exhaust port and voila minimum 10psi increase in B.M.E.P Hello engine technology from 1988 instead of 1963. It would still be far from optimum but it would be a damn sight better. When Keith ships those 110 engines I will have my Stuska lie detector ready to go.

BME102Evo-Great Motor!!
 

Say SuperJ:
Here's another piece of data for the HP wars. On the Amelung Modellbau website, they've posted some dyno tests of the ZDZ-160 with various K&S tuned cans. From memory, it's about 12 BHP. They also posted results from some German mag test of a 3W-150 - similar power. So the manufacturers kind of put a wild guess in the ads for power rating....kind of like Detroit did in the 1960s. You know....horsepower measured at the wristpin.

I assume that ZDZ will send you a new motor to replace the one that fragged. Plan to test that one too?

And ^Kris:
The definition of a good engineer is one who knows in which book to find the answer. Usually it's not the engineers that screw up the design, it's the bean counters.

BME102Evo-Great Motor!!
 

Wasn't my ZDZ and I suspect the owner neglected to mention we were pulling the bejeebers out of it on the dyno looking for his missing 2.5 hp when it went boom. I heard they told him it would be many moons before he would see a replacement. I can tell you this though the only way that motor was going to make 9 hp was if we gave it a 3 hp shot of N2O.

BME102Evo-Great Motor!!
 

Hey, SuperJ, thhe boost ports, and finger ports idea was considered as a "Crutch" for the old style Echo cylinders, but only gained about 150 rpm for the many hours involved with a grinder and mill to get the work done. .not financially feasible, if you know what I mean.

As for HP numbers. . I doubt you will EVER see me quoting such a thing .. strictly RPM /prop size because that's the only way you can really relate in THIS portion of the hobby ..

Now. . WHAT makes you think that BME has not done their homework on their new cylinders and gotten it RIGHT with the new design??? You sound to me like the same folks who said the Earth was flat, or that a Wheel driven car could never do a quarter mile quicker than 8 seconds. . . THOSE people were Engineers too, remember. . .

Remember. . BME has gotten more out of stock weedy style cylinders in their 102's than most anyone else has. . power per cc considered. With the new jugs. . I really don;t think that even YOUR nephew could do much to improve them, and then it would be to compromise something jsut to get more top-end power. . which is the exact OPPOSITE of what BME is trying to do.

See. . YOU want power numbers. . . . BME wants midrange tractability as well as a pretty good top end .. and as EVERY engineer knows. .. the two ARE mutually exclusive.

You REALLY just do NOT understand the design concepts and overall ideology behind the BME line of engines. . do you???

ANYONE can make top-end power. . . . . THAT part is EASY. . . but you know. . WE don't use Top End power ALL the time. Think about that. .

BME102Evo-Great Motor!!
 

my brain hurts!!

Darin

BME102Evo-Great Motor!!
 

The only way you could add that much window area and pick up so little performance would be if the crankcase volume is too small(probably), or the intake valve system is too restrictive. I don't know call me a skeptic. What makes you so all fire sure they got it right?
True enough statement, if we were having this discussion in the 1970s when the Mahle and Kioritz cylinders were first designed. If you think they still are mutually exclusive again join the 21st century. Go ride a RAVE equipped Sea-Doo or Ski-Doo or drive a YPS equipped Yamaha bike or kart. Stump pulling low end torque and screaming top end power can and do coexist happily in all the modern power valve engines and have for some time now. For the record back in the day when the Mahle and Kioritz stuff was originally designed the specific output king the walking boss of the two stroke world both snowmobile and bike was the Rupp 440 Nitro. Now lets see who built that motor? was it kioritz(echo)? Nope. Was it Mahle?(sachs,dolmar,makita,others) Nope. Couldn't of been Rotax so who was it thats right you guessed it dumb stupid simple ZENOAH. The only engine within spitting distance was the Mercury Sno Twisters 440 built by another lowly industrial engine maker, Kohler.

BME102Evo-Great Motor!!
 

SuperJ. . you STILL don't get it. .

Take any one of those motors you WANT in an airplane. . make it weight LESS than 4 lbs. . and do it in an opposed twin package. .

You make ALL these claims about how things "Should be" Well, YOU are the Engineer. . time to put up or shut up. I say. . DO IT!!. . THEN talk about it. If you can't, then you don't know what you are up against.

If YOU can do it. . I'll buy at least 2-3 of them.. .But price them at $1100 or less.

BME102Evo-Great Motor!!
 

Kris and diablo - I think you are missing superj's point. I think he is trying to say that for the outrageuos price we are forced to pay for these engines, we ought be getting the performance the rest of the 2 cycle world has been enjoying for the last 20 years. I mean lets be realistic, could you not buy an engine for your car for $1500?
I'm sorry, but I do not think the prices being charged by the engine manufacturers are fair.... not even close.

BME102Evo-Great Motor!!
 

Desertrat wins the kewpie doll. Kris^ you are really thinking inside the box man. If the engines in question had specific output where it should be for the money the manufacturers want to charge, a 60cc twin would pull like the 100cc engines they offer now. If that happened all your weight this weight that bull would need quite a rethink wouldn't it? Stop thinking lightest 100cc class motor and start thinking lightest engine that will pull X prop and my notion becomes clearer. When that happens I might think about buying a $1500 purpose built engine but until then I'm sticking to industrial engines where the costs are in line with the performance.