capthis

My Feedback: (67)

The plane in this thread. http://www.rcuniverse.com/forum/m_31...tm.htm#5405620

lovefool

Hi, I am gald to find this thread, since I was condiering to buy Seagull Yak54 90. This model has been available here in Japan since Feb 4th.

First I thought to put Zenoah G20ei, but it seems not enough power for 3D, so now I am thinking to put FUJI Imvac BT-24EIS. I am wondering how this motor fits in 18cm cowl and 2.0PS is enough. Any suggestion is welcome.

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Yak 54 90 Manual
http://www.seagullmodels.com/sach/53.pdf

Zenoah G20ei (G200-PU)
http://www.horizonhobby.com/ProdInfo...0EI_manual.pdf

FUJI IMVAC BT-24EIS
http://manuals.hobbico.com/fji/fjig0125-manual.pdf

69 roadrunner

Lovefool why would you add all that weight almost 4lbs. on this plane when you can get the same power from a satio 125 at half the weight runner

lovefool

69 roadrunner, I understand your point. The weight is a big factor for 3D.

I think gas motor has some pros like cheaper, clean, inexpensive fuel, less field equipment and so on.

Saito 125a (660gram, 2.2HP, 40,500yen)
BT-24EIS (1350gram from FUJIIMVAC, 1700gram from Hobbico, 2.0HP, 24,360yen)

I have flown electric for three years now, and I have NOT flown glow motor for more than 10 years. I had been hesitating to restart glow.

69 roadrunner

Lovefool go electric runner

lovefool

Nooooo, I am not RICH to buy battries for 90-120 class plane!!!

69 roadrunner

tHATS WHY I DONT DU BIG ELECTRIC I HOPE SOMEDAY THE PRICE WILL COME DOWN UNTIL THEN I STILL THINK YOUR BEST CHOOSE IS TH 125 RUNNER

tkg

My Feedback: (1)

A G-20 weighs about 45oz with ignition and battery. It will turn a 15x8 APC in the 8700 range. With a header and canister it will turn 9600+ on the same prop

lovefool

I have ordered my Yak yesterday, and it will be delivered tonight. FUJI IMVAC recommended me to use BT-32EIS instead of 24cc. However BT-32 has longer shaft(154mm) and rear mounted muffler, so I need to modified motor mount of Yak to install BT-32. BT-24EIS has 141.5mm length and Yak requirement is 140mm. (exact match!?)

I have not deciede motor and ordered yet.... FUJI BT-24EIS, 32EIS, Zenaoh G26EI or Saito125.

capthis

My Feedback: (67)

Did you look at the weight numbers listed above? The Saito 1.25 is half the weight of the gasser. I understand wanting to go gas, I really do, but this plane is just simply to small for it, and adding that much weight is going to kill it's good flight performance. The lighter an aerobatic plane is the better it is going to fly.


On a second note I ordered the Funtana 100X carbon gear yesterday to install on my yak, and also picked up a new JR 7202 radio system so I will be ugrading the servos in mine to the JR digital servos that come with that radio system.

Still haven't flown it yet! [&o]

69 roadrunner

Capthis let me know how the landing gear fits whould like to put on mine i hope to madin this weekend or next runner

sowega flyer

Well, I went to the LHS today and they just happened to have the yak sitting on the shelf...now there is a big bare spot where it used to be.

gr8taz nitro

My Feedback: (7)

lovefull, if your serious about gas you might consider the evolution 26gt2 for the motor. Engine only weight is 33.6 oz and the inverted pitts muffler adds less than 7 oz. Yes it's heavier than a saito 125, but having to run a 20 oz tank to get more than 6 minutes of flight gets kinda expensive. I'm running a 10oz tank and getting 12 minute flights with plenty in reserve. It's also a beam mount engine so other than re-drilling holes to set the motor inverted, you won't have to modify the firewall to make it work. Power wise the evo isn't a slouch either, I'm spinning an 18x6 prop at better than 8000 rpm and the motor is still new.

lovefool

gr8taz nitro, thank you for your advice.
I know Horizon carries evolution 26gt2, and QQ put this motor on his Yak 71. Since I am back in Japan, I don't know I can buy this motor in Japan. ( I know some shop carry DA and 3W, but never seen Evolution.)

I have still have not ordered motor yet.

gr8taz nitro

My Feedback: (7)

If you can't find an evolution motor, check on MVVS 1.60
It's the same motor, MVVS makes the motors for evolution. Good luck with whatever you choose to install.

lovefool

gr8taz nitro, I have quickly searched "MVVS 1.60" by google, but only site found seem to locate in US. ( at least English pages.) If I decide to use Evolution, I will talk to one of my friend in US who knows marketing manager at Horizon Hobby.

Anyway, first I wanted to use a small gas motor like G20ei or BT-24eis, then started to searching a good plane for this motor. The plane I was looking for was 3D capable 90 class airplane. Extra and Edge were eliminated due to high wing loading of this class.(at leat models I can get here.) I remember Seagull Harrier 90 that flew good by a friend, but not possible to get it here. (discontinued in US as well) Then I have found this Yak from Seagull site that will be newly released in Japan in FEB, and this plane has more wing area and less loading.

As many people here recommended me, this size of gas motor and 3D flight may not be good match. If I stick to this motor, maybe I will enjoy only sports stunt. If I really want to do 3D (so far not capable tho), I need to choose Saito125 or get a bigger motor (like DA-50) and matching plane.

A friend of mine flew big gas plane (100"+DA-100 and 124"+ZDZ-160) and he really impressed me. Also attending Joe Nall 2006 was amazing for me. (Thanks Frank Nall, QQ ..)

I have started C/L 37 years ago, and started RC glow 25 years ago. I still own more than 10 glow motors, a starter, a analog tachometer, a fuel pump in Japan...I have not using this more than 10 years. So I only had been flown electric planes in US for a few years, since I thougt I can't bring big planes back to Japan and there is no big enough field for gas models. However the new place I moved has a big field ( actually soccor field ), so I have decided to get a gas model. So moving electric to gas skipping glow.

I will keep posting of my motor selection as well as building process. Also I will read this thread to know modification tips for using gas motor. (hinges? linkage?)

Thanks for all advises.

Flyinhi1

I've started the build process on mine now. I'm impressed with the accuracy of the cuts and how the straight the horizontal and vertical stabs mounted on the fuse. No sanding or tweaking whatsoever. The layout of the inside is well thought out. Now that I have most, if not all of the equipment for this bird, the build should move along at a good pace. I really like this plane more and more as I dig further into it. I'm following the assembly manual pretty much to the "T" except I installed a Sullivan tail wheel kit before attaching the horizontal stab. You can reach down inside the rear of the fuse and with some long nose pliers get the included blind nuts started for the Sullivan tail wheel mount. I also used blue Radio South CA hinges, don't know if they were 1/4 scale, but they were just slightly narrower than the stock hinges. Also, I had to change the stopper for the fuel tank to accomodate gas. Used a Dubro stopper for that and 1/8 O.D. brass tubing with Tygon fuel line. I had to cut and stack the stock stopper on top of the Dubro stopper to gain the necessary thickness to fill the neck of the stock fuel tank.

lovefool

Flyinhi1, are you put Zenoah G26a on your Yak?
Plese keep updated me during building your Yak. My collegue is coming to Japan next month, so I will be able ot ask him to get some hardware for my Yak, if I need.

So far my choice is FUJI IMVAC BT-24EIS. Our local club president has a good communication with FUJI IMVAC, so I can expect good support from them.

Chumley

Lovefool,

There are a couple of good Yaks on the market with 72 - 73 inch wingspan that would do everything you want with one of the smaller gassers. Quique Somenzini is one that offers a 73" Yak made for smaller gas motors and Aero-Works is coming out with a 72" Yak next month. I'm not sure what is available in Japan, but you may be happier with something with a little more wing.

Chumley

lovefool

Chumley, thank you for recommendation. I have been knowing QQ's homepage has a Yak with Evolution. I will look for Yak at Aero-works later.

Anyway this is my first gasser. The biggest model I ever built was 40 class before, and I have been flying only 400 class electric for a few years. I know a lot of concerns for big model and gas motor, and I have several friends here to teach me as well.

Eventually I have been working for a project with one of my friends in US, and we advised our prototype at Joe Nall 2006. He brought the product to QQ recently and tested on QQ's Yak turbo (turbo prop). The result was just okay, and we need to work on this project that will suit for a turbo prop.

So QQ may give us one as a reward. (I better ask a bigger model and a motor !) Oops, first I need to update HW and SW.

lovefool

Flyinhi1

Lovefool, yep....I'm putting the Zenny on mine in the face of all that think it won't work well.

lovefool

Flyinhi1, so I am in the same boat then ....

capthis

My Feedback: (67)

Got some new carbon fiber landing gear today. This is for the Funtana 100X. The gear is roughly the same size as the yak gear only about 3/4 of an inch shorter which shouldn't make much difference.

The stock gear weighs 6.52ozs. The carbon gear weighs about 2.79ozs. The new gear also bolts on with only two 10-32 bolts instead of four 1/4 inch bolts like the two piece aluminum gear does so that should save a litle more weight as well.

All told this will save about 4 ozs or just a tad more. Shaving a 1/4 lbs off a plane with size is a worthwhile investment. IMHO

sowega flyer

I'm going to start mine this weekend. I'm planning on pretty much a stock build unless I see some things along the way that I would like to change. I might take some tips from here on lightening the plane a little but a sport flyer is what I'm after, not an all out 3D machine. I will be using a GMS 120 for the powerplant, but don't know yet what size prop to use. (Anybody have any suggestions?) So far, I'm very impressed with this plane and this is my second seagull plane so I know the quality should be good.

jbloom

So I see this plane today at Horizon Hobby and thought man I have to have that. I had the Hobbico Sukhoi, but after a few SLIGHTLY hard landings, and replacing the bottom of the fuselage just too many times, I wanted to get something else. I see this one and wonder if it isn't the perfect replacement.

My question however is this. The engine I flew on the Sukhoi is the one I'd like to move to Seagull Yak. That engine is a Super Tigre G90. I don't fly 3D, so I'm just looking for an engine to pull this plane through your basic loops, rolls, knife edge etc etc. Will this engine be enough, or am I'm gonna find myself whinning for more power?

John