Originally Posted by oachidori

Hello,
For all owners of this plane and still fly with them: where do you exactly have cg?
I ask you because i have a heavy engine(MVVS 58) and at the moment my bateries are on the tube and i still need 10 clicks for up elevator.
Tks for your ansewrs.

For most of us..this plane builds tail heavy and we put our batteries inside the motor box. If yours is nose heavy just move batteries back a bit more.

Hello guys,
I have this Extra 91' with this setup. In this setup the plane is nose heavy 11 clicks on elevator for level flight and inverted climbs, so seems tail heavy. Your point of view: motor angle? Or if you have any advice?
Thanks for your answers.

[QUOTE=oachidori;2865103]Hello guys,
I have this Extra 91' with this setup. In this setup the plane is nose heavy 11 clicks on elevator for level flight and inverted climbs, so seems tail heavy. Your point of view: motor angle? Or if you have any advice?
Thanks for your answers.[/QUO
Edit....after re reading your post...it sounds like you need up thrust but having said that...I have had many EF airframes and have never had Any thrust angle issues...

Originally Posted by oachidori

Hello guys,
I have this Extra 91' with this setup. In this setup the plane is nose heavy 11 clicks on elevator for level flight and inverted climbs, so seems tail heavy. Your point of view: motor angle? Or if you have any advice?
Thanks for your answers.

What motor ?

Originally Posted by gapple12

What motor ?

See post 8808.....

Originally Posted by gapple12

What motor ?

MVVS58 PROSPORT with MVVS pipe. I have to say that the engine and ignition have arround 2.2 kg. I have too a servo for choke, because i use easy start. So i have some weight in the front.
What i am interested, for planes which fly well where do you have exactly CG, mm from the leading edge. I rechecked all incidences and all are good. The firewall is on 0.

Originally Posted by oachidori

MVVS58 PROSPORT with MVVS pipe. I have to say that the engine and ignition have arround 2.2 kg. I have too a servo for choke, because i use easy start. So i have some weight in the front.
What i am interested, for planes which fly well where do you have exactly CG, mm from the leading edge. I rechecked all incidences and all are good. The firewall is on 0.

I have this with a DA 70/TD110 can, and a direct drive servo in the tail and balance is perfect with batteries forwards.

As far as CG is concerned I fly the inverted 45 test - that seems to suit my purposes very well (a gentle arcing over).

Solutions to your problem? 1. Remove the pilot figure - it adds weight behind the CG. This alone might solve your problem - I recollect they are quite weighty. 2. Replace the elevator servos with a pair that are very light and powerful - ie savox 1270tg - the multiplier effect works well for you here by removing weight from behind the CG. 3. If you really had to add weight forward you could use a "heavy" prop and spinner backplate - in my experience the mejzlik props are quite a bit heavier than the equivalent Falcons (for example).

Good luck!

So, i measured again the location of cg with this method.

Balancing your RC airplane (5 min 17 sec)

And there are like in the picture. Yours where is it?

I have DA-50 for my Extra 91".

Curious, what batteries are you using for RX and Ignition? Looking for as much light as lipo 2s batteries.

I believe a DA 50 for this plane is a mistake. This plane was designed for a 60 to 70 cc and the less powerful and lighter 50 will need lots of added weight up front to Ballance which in turn will take even more power from the already weaker engine.

Originally Posted by oachidori

Hello guys,
I have this Extra 91' with this setup. In this setup the plane is nose heavy 11 clicks on elevator for level flight and inverted climbs, so seems tail heavy. Your point of view: motor angle? Or if you have any advice?
Thanks for your answers.

Where did you get your fuel tank?

DA 50 for plane 91? No less than 60 cc

Originally Posted by Puttputtmaru

Interesting so from what I can see on the video the velcro on the battery does not « bind » with the velcro on the straps. It is basically a Male/Male (or Female/Female) match.

Is the velcro necessary to prevent some slippage or is it just because it was already on the batteries?

You are right, they were already on batteries. These Velcro, which you see on the main batteries, I left them so that the batteries do not touch the tree, that's all. The batteries themselves do not slip because they fit snugly. As for the small ignition battery, it is clear that I use both female and male Velcro. I flew them for a long time, no problem

Originally Posted by ponyboy082662

Here is how I fixed my issue...if you zoom in you can see behind the prop...4 holes in a plus design...1/2" each

Is it really enough to cool?

Originally Posted by Todua 77

Is it really enough to cool?

Thoes holes are not for cooling....they are to let some air to the carb...on the twin cyl