Yamaha WEIGHTS - MAC YG2!! 80HP Phazer 4-strk, 2-cyl, EFI, 88/123 lbs, liq-cool

NoWingsAttached

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It's HERE!!! Remember back in 2011 when Ernie tried to do a successful YG4 (Yamaha Genesis 4-cylinder 4-strk 150HP) conversion and ran into so much trouble and headache he abandoned it and never did another one?

Remember when I did a YG4 right after it, and it was trouble-free right out of the shop and never quit, way back in 2012? Remember when I went on to be the first guy to sell YG4 kits in 2013?

Remember when Todd Rieck tried to do a YG2 (Yamaha Genesis 2-cylinder, 4-stroke, 80 HP) conversion? It never ran, they even tried to install a turbo to get it to spin the prop, and they abandoned any plans to convert THOSE motors.

Well, after I found out that Norman Lethbridge had built a successful YG2 gyrocopter, I figured what the hey, we're good to go!

My first YG2 customer is flying his Quicksilver floatplane in New Orleans as we write this, and I just took delivery of my second Phazer motor this week ($2200 form my vendor, delivered to my shop) and did some weighing as I unpacked it from the skid. Here's what we found, and IT IS SO EXCITING!!!!

Just 88.4 pounds engine, throttle bodies, hoses, some electrical stuff, remaining engine oil, starter, coils, plugs, thermostat etc.

THIS IS A VERY LIGHT 4-stroke, water-cooled, 80 HP ENGINE!!!

I added EVERYTHING else I could think of except the kitchen sink, and all-up installed FLYING WEIGHT COMPLETE this baby weighs just 123.1 POUNDS!!!

HOLY JEEZs are u kiddin me?? A Rotax 912 UL (is that supposed to stand for Ultra Light? if so, then LOL!) 80HP weighs a whopping 153.8 lbs, THIRTY POUNDS HEAVIER!!!

This engine is more on par, weight-wise, with a 582 Smotax, which is reportedly 117.2 lbs, at just 65 HP.

Here are my facts backed up with photos. I used self-zeroing electronic scales, accurate to within +/- 1 oz for the main engine weighing, and then a postal scale accurate to +/- 1/2 gram for the ancillaries I could fit on it.
1144796
1144797
1144798
1144799
1144800
1144801

Now, looking over the list you may notice I do not include the muffler with the rest of the exhaust. There's a very good reason for this.

FIRST: You MUST have the silencer/expansion chamber on a 2-cyclcle engine, and it MUST be included for a flying weights claim. HOWEVER we all know that a muffler is NOT required equipment on a 4-stroke engine, and is therefore NOT required to be listed for all-up, installed, FLYING weights.

SECOND: Mufflers for the YG2 which are thus a luxury, not a necessity, can weigh anything from a couple of pounds, up to the stock Yammie SS deal which weighs 18 lbs on the sled, friends. Your choice. I'll include whatever you feel you need.

Happy flyin, guys - hope ta see ya'll at Mentone soon!!!

Yours truly,
Gerg
 

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All_In

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Ernie told me that the reason he abandoned the 4 cylinders was... Cannot remember his exact words but it had a delayed PRM range problem compared to the 3 cylinders. That made it troubling. You were making a landing in the spot landing contest and later he said see Greg, "You" just had the same problem when you swung wide descending over the crowd.
 

All_In

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The reasons he did not continue the Viking engine was no consistency in the final design and when the Viking owner had money the price when way up when he didn't it went down.
 

NoWingsAttached

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Ernie told me that the reason he abandoned the 4 cylinders was... Cannot remember his exact words but it had a delayed PRM range problem compared to the 3 cylinders. That made it troubling. You were making a landing in the spot landing contest and later he said see Greg, "You" just had the same problem when you swung wide descending over the crowd.
Greg don't write here as much as he used to. Maybe it's time he come back and stir stuff up again.

Greg never had a problem with rev lag on his Yamaha YG4. The observations made from the ground in the quote above are ignorant. That's not a cut, it's the plain and simple truth. If that is what Ernie took away from Greg barnstorming you in the Air Boss tent during the spot landing contest, it was ill-conceived as he never spoke to Greg after the buzz-by nor did he ask him about what happened. Chris Burgess sought Greg out and asked him what happened, personally, a few hours after the contest.

Please feel free to discuss it with him, since he is the only third party who is knowledgeable on the matter. Here is what Greg said to Chris:

"Every single pilot in that Spot landing contest aborted their first attempt, due to a devilish atmospheric sink hole at the approach end of RW 36. No one was expecting it, and everyone bailed out of their first spot landing attempts. (Chris mentioned he had experienced the same thing on more than one occasion at the same place in the past.)

Now, I had mastered a technique of doing 180° sim engine-out landings from abreast my chosen landing point. Feel free to ask the FAA Sport Pilot Examiner who flew my licensing with me in this gyroplane a few months before this PRA meet, who exclaimed after two perfect landings - one 5 feet from the line, and one dead on it, with 1-3 ft roll - that they were both the most accurate, smoothest, and by far the best sim EO landings he had ever experienced with any pilot at any time, in any type of bird, anywhere. Steve McGowan can direct you to that gentleman if you'd like to verify my account. However, it is well known that I am a lot of things but that I am never a liar. I can be wrong, I can misinterpret information, but I simply cannot and do not intentionally lie. It is part of the curse of my autistic Tourette's syndrome brain, and - trust me - the inability to lie and always be completely truthful is NOT a good thing when dealing with people. People actually NEED to be lied to in many cases! For the contest I chose this type of landing.

As I neared the RW, at the bottom of my 180, the gyro started dropping dramatically and unexpectedly. Not wanting to abort the attempt I flattened the turn with stick and pedals in an attempt to make the contest line. This did not slow the rate of descent appreciably and I could see that there was no way to make the line. Instead of making an ugly landing I added power.

Now, when you add a LOT of power, suddenly (no rev lag), with a very powerful, responsive engine, in a flat turn, you wash out like a four wheel drift in a car.

That is what took the gyroplane over the air boss tent at 25-30 ft AGL, and sent John running, tossing his clip board in the air as he fled. I have to admit I was LMAO as I passed over the tent, John scampering off on my right.

There are some folks who wonder if I did it intentionally. Things that make ya go, "Hmmmm."

But I cannot tell a lie. Maybe my evil Gemini side had a hand in it, but I certainly did not set out to scare the pants off John, or anybody else. I most certainly had no engine lag or any other mechanical problems, the aircraft was perfect."

-------------------

Ernie became discouraged with the time, money and effort he put into his "Yamanator" YG4 project. After that he could not see a way to simply, easily and repeatably install the YG4 motor.

The biggest problem he ran into of course was coupling all that power to the prop, since this required a custom built adapter to fit a standard PSRU to the engine. His solution was to send the motor to Australia and let Neil Hintz do that for him. Neil's gearbox was rather heavy, but the result was fine, except that with Ernie's intake and exhaust the motor would not spin up w/o a clutch. Neil retro-fitted a sprag clutch to the prop hub. It worked for a while, but it cracked with less than 100 hrs on it (needs verification, wiki style).

Had Ernie just bought a snowmobile and pulled the motor himself he would have had an easier time of it. Instead he bought the engine w/o ever seeing how everything was connected, and then wound up tearing his hair out trying to configure the wire harness, etc. According Ernie, and later to other sources, he never did figure out all the limp mode circuitry and the conversion engine would cut out and drop to <3500 RPM without warning, in flight.

What John refers to, above, as "...it had a delayed PRM range problem" (RPM) was not the YG4 engine's fault! It was the result of installing a poorly-designed intake plenum and an even worse exhaust header. I am not going to waste my time diggin up photos of the Yamanator from 2010/11, but here's what I am going to tell you about it.

The early stock 140HP YG4 intake "silencer" has 3" velocity stacks terminating inside a large "shock box" which also houses the foam filter. I am building the first ever 165 HP Yamaha (stock, out of the box HP) for Geoff Resney, PRA Ch 18, and it has 5" velocity stacks. Ernie's intake fuel bodies were attached directly to an empty, hexagonal tube. NO stacks, it was attached directly to the box via the 4 each FI throttle bodies' intakes.

What was far worse than this was the exhaust. I suppose it was done at RFD to (1.) save money and (2.) simplify the fabrication to reduce time and trouble building the header set.

The headers, the pipes that attach to the head and end in some sort of collector where they join together either as 4-into-two or 4-into-one, MUST BE 21-24" for suitable mid-range power. The RFD header was only about 4"-6" long, terminating in a horizontal can that served as the collector/muffler. Yeah, that's the cheapest, quickest, easiest way to do it, but it is the worst thing you can do to this engine.

Look, the YG4 is a 5-valve-per-cylinder, 4-cylinder, 4-stroke 998cc engine built for 16,000 RPMS in the R1 motorcycle, and cam-tuned to 10,500 RPMs for peak power in the sleds. IT HAS TO BREATH, plain and simple. This is not your 1950's technology thumper that bumps along with two valves dumping into a massive cylinder moving half that speed, or in the case of a Lycoming 1/4 of it. The Yamaha YG4 engine produces as much power as a Lyco IO-360, or IO-320, on HALF the fuel - by breathing that much more efficiently!

When you jack up the intake, then you jack up the exhaust, you pay the price: Loss of response, as well as power. This is not rocket science, nor is about YG3 vs YG4.

I tried to educate Alex and Paul about hypo engine breathing when they showed up at Bensen Days for the first time in 2015 with their Tango Gyro YG3 built with a junk intake and 3-into-1 stubbies dumping into a can - something they copied off Ernie (just like they copied Ernie's Dominator frame years prior).

I flew one of these gyros with a heavy passenger. Either you fly WOT or you sink, there is no mid-range power to speak of.

After a few years, our friends at Tango Gyro were finally convinced. Every Tango built since has a fantastic exhaust copied from the ones I make at MAC.

Now, about that Viking...how much did you say it weighs again? Goeff Resney's YG4 Air Command tandem is getting a 2011 Yamaha Apex motor which weighs about 120# with the starter attached. All-up, installed, everything except the battery, it will be 170 lbs, 165 HP (without any engine mods - factory stock). The exhaust is titanium, with stainless steel header flanges and stub bellows flex couplings. The titanium collector is cast, and contains a butterfly valve which is electronically controlled by the ECU and a servo motor - much like power windows operate on a car.

The pipes at the head were 1.285" ID on the earlier YG4. These are now 1.413" ID. This allows better top-end HP, resulting in the gain of 15 HP over the old exhaust system, while INCREASING mid-range power 10% by closing down mid-range flow and increasing back pressure. Best of both worlds.

Yamaha introduced the butterfly collector, named EXUP, in 1983. One year later, Honda started building them. I don't know if that was a rip off or if they bought a license, I only know Yamaha is king and nothing beats a Yamaha on a gyroplane. They introduced EXUP on their sleds in 2011.

Now tell me...what was it you were saying about Ernie's Yamaha 4 having throttle lag issues, again? I've completely lost track of the conversation we started out with here.

Oh, YEAH!

MOHAWK AERO CORPS (MAC) IS NOW OFFERING PROVEN, RELIABLE 80HP YAMAHA GENESIS 4-CYCLE LIQUID COOLED EFI NA ENGINES FOR GYROCOPTERS (& other aircraft) THAT WEIGH ABOUT THE SAME AS A ROTAX 582 (installed weight).


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I will post build photos of the next one - the a YG2 Blue Bee (Honey Bee I bought from Matt with a Hirth 60HP in 2007) as I get the gyro built, but right now still busy with Geoff's AWESOME 165HP YG4 Air Command! Time to quit writing and get back to the shop.
 
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