View Full Version : EFL and Pro pinion

11-18-2011, 04:09 PM
We are running a 13T pinion on our 450M in our 450 pro in lieu of the 14T. This is because with Thunder Power batteries and a 100% flat throttle curve the heli performs really well with no bogging. The 100 90 100 curve just didn't do as well.

I see that an 11T pinion is now available for the Pro and EFL. If not running a governor, would the 11T be better using a 100% curve than the 12T running the 100 95 90 95 100 per the manual?

Just getting my order list together.

11-18-2011, 04:16 PM
The 11 tooth will end up giving a little more torque, but you will lose a little headspeed. So if your like me and like a ton of collective and not crazy headspeed, its perfect. I like to run 14-15 on my collective, and about 10% lower headspeed. I would rather do this as it nets me a little more flight time than running a higher headspeed with 12-13 collective.

One thing is for sure, you will lose about 9% of your headspeed and gain flight time and torque, you will also see lower temps on the motor and esc as they will not be working as hard if your set up collective and cyclic stay the same. so you will most likely want to run 100% flat or a very shallow V, like 100-96-100

Hope this helps..

11-18-2011, 04:30 PM

That is perfect information. I have found the same things were true on the 450 and it appears it applies to the 500. I am going to pick up an 11T pinion and plan on the 100 flat throttle curve. You are right. Even when my boy is banging the sticks around pretty hard the speed and the motor never get hot. I'll throw the 12 in the bin with the 14T and put it on when he is ready to start competition stuff. Right now he is just enjoying being on the team and is throwing it around a bit.

I appreciate the good advice so far and a big thank you for the advice not to buy a 70 dollar bec.

11-18-2011, 04:44 PM
No problem.. Another thing to look at if the machine is going to be used for hard 3D would be using a good tail servo and a little larger tail blades. the stocker does pretty good until you get in to hard collective. I am using the Outrage/MKS 9188, IMO its the best tail servo available right now. I beat on my 500efl pretty good and the tail holds WAY better than with the stock servo, especially when I really get on the collective...

As far as tail blades, the KBDD 70mm and EDGE 72mm have a little more surface area than the stock blades, so they hold much better than stock as well.

11-18-2011, 10:28 PM
I appreciate that!

11-19-2011, 09:41 AM
Was it difficult to get a full size servo to fit? I have a ds650, a turnigy BLS same as MKS 980 and a BLS254 lying aroud I could use in my build. Not sure which one, maybe the futaba or turnigy?

Regarding throttle curve, on my ESP I use a 100-80-100 BUT I also have a cyclic to throttle mix and also a rail to throttle. The headspeed stays constant in all maneuvers, very happy. IMO a simple throttle curve cannot be optimal as you are forgetting about cyclic loads.
What I do is tweak the TC on punch our until HS holds. Then do full cyclic flips and do a P-mix ail and ele to throttle until it holds. If you want add 5% throttle with right rudder and -5% on left rudder. Rock solid! Of course HS decays with battery voltage same as flat curve. Difference us you waste way less energy in a hover or when unloading the head and also avoid overspeeding.

11-19-2011, 11:50 AM
Servo was easy to get in there, just a little dremel work. As far as throttle curve, I use 45-90C packs so dont really have a problem with HS decay. I dont really notice a HS drop, and just fly through any variances. its flying really good. I also have a scorpion motor in there, so that helps with HS as well. the scorpion has GOBS of power and runs VERY cool, compared the the 500mx.