RJetss

Ok, I've read alot about a few of the SPE engines, but finding nothing on the SPE 43. I just purchased a 74" wing 25% Yak with the SPE 43. Anyone out here have this engine? It's my 1st gaser. I guess the price couldn't keep me away. Also this engine was with a combo that I bought from PeakModels. Think the engine is over sized? I'm now seeing alot of setups with this size plane using 26's or 28's.

ultra6a

My Feedback: (27)

I have the same combo and hope to maiden the plane today. I'll let you know how the combination works.

Walt and Sage

Yes, you are right as it (in MY oppion) is to large for a 25% Yak
I am installing the SPE 43 cc in a 29% Giles U/L witha 78 inch span and 1100 sq inch wing..

It will fly but you may have tip stalling at slower speeds... BE very careful...

RJetss

Ultra........Did dying to find out if you did the maiden on that today, and how that motor performed.

ultra6a

My Feedback: (27)

You're opinion was dead on. Took off with my SPE 43 and it tip stalled at about 30 feet. Plane was destroyed!!!


RJetss, If I had it to do all over again, I would go with a 26 or 28 cc engine.

RCVFR

My Feedback: (7)

Bummer! Sorry to hear your plane went in. []

togatoga

My Feedback: (42)

I'm getting about 6800rpm on a 20x8JXF prop running on the first tank.I'm using a Rcexl ignition system.Have the engine in a midwest cap232 that used to house a saito300. I lost over a pound with this new engine in place. Hope it flies OK.

karolh

Why would using a 43cc engine which only weighs a few ounces more than say a 28 cause the model to tip stall, and I'm assuming while accelerating from a takeoff position ..... just curious .

Karol

RJetss

Wow Ultra..Sorry to hear that Now I am really thinking and uncertain. My largest plane is a Frenzy by hanger 9 with a OS 120 surpass in it. This is my first gaser and little larger scale plane. So can you tell me exactly how you had this mishap? Weight wise I wouldn't of thought it made that much difference, just checking the CG. Peak emailed me and sent me a picture of that motor in the same plane and said the guy loved it. LOL What's that mean? Anyways again sorry to hear what happend to ya man.

jfstrama

I have the EF 74" Yak with a Brillelli 46cc and it has NO bad tendencies what so ever! It handles like it was designed for this engine (even though it was originally designed around the OS160).

Can you describe exactly how this engine combination would cause tip stalls? It would have to be VERY overweight for that. (Don't forget that you can cut down the fuel load significantly over the glow engine).

MadDog Joe

arobatx

Wing and Airframe Design...nothing to do with the engine choice.

karolh

Just as I thought.

Karol

ultra6a

My Feedback: (27)

I started the engine a couple of times, did range tests both times, checked control surfaces to make sure they were working properly. Everything checked out fine on the ground. Taxied plane out and then throttled up for take off. The plane traveled about twenty feet on the ground before taking off. All appeared to be going well as it was gaining altitude and flying straight when it suddenly began to roll to the left. I tried to correct with right alieron input but it didn't respond. There are several people who have this combination and fly it without any problem. Not sure what the exact cause of my crash was. Can only conclude that I did not have enough air speed at take off.

Walt and Sage

I own TWO CRRC 26cc and ONE SPE 43cc
I do not have a scale but I do not need one as the 43cc weighs
much more than the 26cc...

It would most lilely tip stall at the WORST times like landing....

ALSO read the post 3 above....
It DID JUST THAT and is in airplane heaven now...[]

arobatx

I fitted a G62 in a plane designed for a 1.60 two stroke glow. The plane came in at a weight of 15.9lbs instead of the advertised 13. Am I tip stalling....nope. Do I respect the airframes limits...of course. The wing area easily supports the AUW with my engine choice, and it is up to me to power it appropriately throughout the flight. Can those of you having problems tip stalling, and blaming it on the powerplant up front, please post the wing area and AUW of the planes in question? Not the advertised weight, but your measured weight of the plane. A wings design will come into play as well, remember some of the older CAP models?....they could high speed snap in a turn, had nothing to do with the engine, or even being overweight, it was an acknowledged limitation of the design at the time.

togatoga

My Feedback: (42)

A 43 is close to a pound heavier to a 26 engine. That will result in a higher stall speed.If a plane has a tendency to tip stall because of design or already has a high wing loading, a heavier engine will aggravate the situation. The smaller the plane, the less tolerant it is to any weight increase.

Walt and Sage

YOU are so right !!!!
I have seen MANY planes with large motors up front and then weight added to the tail
to balance and then they just CAN NOT understand why it is a handfull ....

arobatx

tag Karol, you're it

karolh

Yeah I guess, but really no need to respond as you did an excellent job of explaining your senario which is dead similar to the line I would take in explaining how I shoe horned a G23 into a CG Extra, which though it gained 2 lbs. in it's AUW with most of it up front, it still flew like a charm and developed no bad tendencies. Similarly look at the Stick designs, it's almost impossible to overpower them, they just crave it. It all depends on the basic design of the airframe and nothing more.

Karol

togatoga

My Feedback: (42)

I think the operative word is "tendency". You would have to agree that a lighter plane flies better than a heavier one.Thats why competition planes strive for the lightest possible setup. Plonking a larger and heavier engine does not necessarily improve performance but it does mean that the Vstall and landing speeds would be higher and handling characteristics altered. If a plane has a "tendency" to be snap happy, the condition will be aggravated with a heavy engine and additional balance weight behind.
What Walt was trying to say is that some planes due to design and heavy airframe (CMpro planes like the Yak in particular) have a "tendency" to snap if the wingloading goes up which is plausible. Using a large and heavy engine will work on some plane designs like the thick foiled stiks but I bet it will not fly better than a lightly loaded one!
I keep my planes light and resort to higher capacity engines only if the weight increase is very minimal.

karolh

Walt and Sage,

Take special note of this part of Ultra6a's comments.

Karol

jedijody

My Feedback: (1)

All of the explanations given here for this unfortunate mishap are good info and could apply. That said, I have a lot of experience with this exact plane and both gas engines discussed (sell them, build them, fly them). The SPE 43 is not exactly the lightest 40cc class engine but this plane and engine combo does work just fine together if properly balanced. It should have had an all up weight of a little under 12 lbs. It would have had a wing loading of about 28 oz./sq.ft. With all due respect Walt, not overloaded for a Yak, unless it was left to nose heavy. it would then need more than usual air speed for a Yak for landing but this Yak does not have any "tendancies" for tip stalling, it's stall characteristics are straight forward. One thing I would not rule out, if you lost radio link with the plane the tendancy would be for the plane roll left as described from engine torque (maiden flight, untrimmed) but right aileron would correct it if it was there, even at slow air speeds with the wash of a 20 inch prop blowing over it. I also am flying this exact plane with a CRRC GF40I up front and it is awesome, it floats like any other Yak I have had and comes in like a baby. Power to weight ratio equal to a 16 lb. plane with a DL/DA 50 pulling it, no bad issues at all. The CRRC is about 5 ozs. lighter but that is not enough to be significant.

Jody

OCR99

My Feedback: (3)

IN OTHER WORDS IF YOU STAY AT 28 OZ SQ FT OR LESS YOU SHOULD BE OK WITH EITHER ENGINE.

RICK

OCR99

My Feedback: (3)

IS THAT A 74 INCH ALL I SEE IN 25 SIZE IS 71 INCH

RICK

RJetss

OCR99.....That's my bad. It is a 71" 25% I think I wrote 74". Sorry about that.
You all that gave imput on this maybe you'd find this interesting. I found another thread on this plane and this is what they said.
http://www.rcuniverse.com/forum/m_79...l%2CYak/tm.htm