nashtm

Hi

I have a spare 91fx with perry pump. Its light and powerfull. (and messy)

Cyberwolf

My Feedback: (4)

Barry has some good points there,the extra 11/2 lbs would prolly ruin the plane for any real good 3-d moves ,but still be a good sport flier and acrobat.
Remeber this the mayhem is not designed for high speed it warns against this in the manual.
Although for short burst I open my 120 YS up and so far never had a prob.
The 91 FX will put out allot of power but will it 3_D the plane the way it was intended ????That I can't answer.

olstoney

My Feedback: (19)

I kinda agree with Cyberwolf. I know that you have the 2 stroker, but you might want to think about a 4 banger for the best combination.

nashtm

[:@][:@][:@][:@][:@][:@][:@][:@][:@][:@]

You guys are saying all the things I dont want to hear !!![X(]


thanks

rclement

My Feedback: (1)

Great.........

nashtm

Hi

I have come to my senses and have decided to put the gas motor in a bigger plane and am looking at a Saito 125 for the Mayhem and my other fun flys.

Thanks for the input.

olstoney

My Feedback: (19)

Good Choice,
You might want to try a YS110 though, it's actually less expensive than the Saito right now . As Barry will agree the YS has more power than the 125 at least at his altitude. Not quite sure here at sea level as I have not seen a 125 perform at our field yet

Cyberwolf

My Feedback: (4)

The YS is a very good choice of engine for the mayhem, And I agree the 110 YS will out preform the saito 120 or 125 at any altitude. Don't get me wrong the Saito is avery good engine,it just does not have the out put of a YS ,there fuel delevery system really adds some HP to there engines.
Plus you can place the tank on the CG without any issues.

nashtm

the problem is that here in South Africa YS is not big but Saito is - however I may look at buy on the net.

Thanks

wxman

I have the Saito 125 and it has been in an amazing choice. Vertical is all day long and no tuning issues at all. My friend when with a YS 120 and the pesky tuning issues of that engine caused so many dead sticks that he eventually stopped flying the plane. Well, he sent it back to YS to tune it, got it back in the plane and flew it twice with both ending quickly with dead sticks. On the second dead stick he lost the plane. The Saito 125 performance is a great choice for this plane and very reliable.

nashtm

Thanks wxman

>>Vertical is all day long
I trust this means *unlimited vertical*

I have had great results with my 91fx's but the noise, revs and non linear throttle responce has gotten to me but I think the 4 stroke will restore my joy !!!
Do you have the the rudder servo in the tail with the Saito ?

Cyberwolf

My Feedback: (4)

YS engines are not for everyone ,They do tune different from the others.IT does take some reading and hands on to get the engines to preform correctly .If your used to just setting the top and bottom somewhere close and go fly ,I would say the YS is not for you .Yes they do take a little longer to get in tune,maybe 5 mins 10 at the most but once its there its there But the 120 YS in my mayhem has never once died in over two yrs of flying and at around 300 flights I would say thats a good track record.
If a YS engine is dieing its either not tuned correctly,wrong prop size incorrect plumbing to the tank or the wrong tank itself the wrong or a bad plug or it has a mechanical problem of some sort .
I had a 63 that I just could not get to run properly sent it back to YS 3 times ,finally they sent me a new engine ,but by that time I had had enough and sold it unused .
With the exception of this 120 thats in my Mayhem I have had them all die at one time or another ,usually because of a to low throttle on a violent move .
Anyway I will agree the saito is more user friendly when it comes to tweaking the tune ,but still wont hold a candle stick to the preformance of the YS ,plus theres the tank issue try putting it on the CG running a saito WO a pump and see how long it runs if it runs at all.

BTW I do own several Saitos so its not like I don't like the engine or anything and they all run flawless, I am just giving you a fair example of the 2 engines from hands on experience

I am sorry about your buddys plane ,but here again if they have a hint of a prob on the ground the air isn't going to make it any better and usually ends up in a dead stick and maybe worse.

Cyberwolf

My Feedback: (4)

What size prop are you using on the 125 saito and at what RPM's oh and what % of nitro

wxman

I do have the rudder servo in the tail now and ended up with a CG of 5.75" with battery still reachable in the fuselage... ie. not located in the tail. I am probably going to a CG of 6" soon, but 5.75 is still very landable. I harrier land almost everyone now and can touch the rear wheel first about half the time, so the the 5.75" is definitely not the limit on easy landings with this plane.

FYI, I did the rudder servo closer to the tail than the elevator servo and some spacer blocks to keep it from touching the other side of the fuselage. It is covered nicely hidden under the elevators too.

nashtm

>>Vertical is all day long
I trust this means *unlimited vertical*


wxman

*unlimited vertical* - I need to hear you say it !!!

wxman

It is easily unlimited vertical with all the props I have used.... APC 16x6, APC 16.5x5W, and APC 17x4W.

nashtm

Thanks wxman

I have orded my Saito 125 !!

rclement

My Feedback: (1)

Out of the three props you have listed, which do you find to work the best with the 125?

wxman

That is a great question. The funny thing is that I have flown the plane for about 8 months now and I still don't know the correct answer yet. I love to fly slow of the verge of stalling the wing a lot. I love harrier manuevers, high alphas, high alpha knife edges, hovering etc. I am also a big fan things like flat spins, inverted flat spins, knife edge loops, etc. So, my needs are very much not for speed, but I want response and vertical. I tried the 16x6 and it was faster, but I was not happen with its spin up when needed to correct in a hover. The 17x4W spun up very fast but the rpms weren't what I wanted. The 16.5x5W was what I ended up choosing. Honestly I thought about trying a 16x4W as well, but I am not sure my hobby shop has one. I heard that prop may go supersonic though, so I don't know I want that much noise. Has anyone here tried the 16x4W or a Zinger 16x5?

Jack Hyde

My Feedback: (1)

At 10,000 rpm a 16.5 prop tip speed is 720 feet per second which is abot Mach 0.7 at 70deg F. You aren't going to get supersonic.

grandad1

My Feedback: (22)

rclement I am runnig A 16/4/w on my Saito 150.I have had biger ones on it but they like Wxman said it flew too fast.I have not went supersonic with this prop.So I don't think you would have any problem with the Saito 125.Hope this helps.


Joe

wxman

Joe,

I will order one today and try it then. I think would like the quicker spin up of the 16x4W, I think so I will go that route.

On a side note, I decided to take the CG back from 5 3/4" to 6" and it made a huge difference on high alpha manuevers. The inverted high alpha flight is beautiful and the inverted harriers are great now. Of course the hovers are easier. The landings were getting close to needing up elevator to bring it down, but not quite yet. I could still easily harrier land and a very slow speed. I am not going back to the 5 3/4".

rclement

My Feedback: (1)

Joe, Thanks for the info. Saito 150 eh! That sounds like gobs of power....

rclement

My Feedback: (1)

Wxman, That's interesting about the CG. I'll have to check mine and see where it's at. I don't think it's that far back so I'll have to try it out and let you know.
I made a nice wing bag for mine. Very easy to do. I'll post some pics when I get home.

Jetdrvr393

Hey everyone, has any had any problems with the stock fuel tank on this plane. I have a Mayhem 40 and I can't get the tank more than half full. What's the deal?