Helibug

Hi everybody,

I built my gasser some weeks ago and i want to setup the ALIGN Governor, my question is.

What is the recomended head speed for Sport and 3D? I am using a Zenoah G290-RC and a RJX gasser muffler.


Another question is, what is the working temperature for this motor?

Best Regards,

Francisco Morales.

Hi Morales, I see you have had no replies so I thought i would give you my ideas. Perhaps others may not agree but here goes anyway.
I don,t think the align governor will work very well, its rpm range is not good for gas engines that do not rev as high as the nito's it was designed for. You can "cheat" by working out the math but may have issues with overspeeding especially on decents.
My advice would be to go for a GV1 where you can set the ratio properly read the headspeed or engine speed from the display and mod the secret menu to improve gasser use as advised by rbort on other forums.
Gassers do not need the head speed of nitros as the torque of the engine is so much higher than nitro's.
The helibug flies well at 1500rpm, and 1650 is good for sport, with 1750 ample for 3d. Managing the collective is what it is all about and improves your skill level for all types of heli's.
I found that 690 blades give faster roll and flip rates for 3d flying. I know that others fly at 2000rpm but my heli does not like it as the vibration level increases affecting the gyro with very little increase in performance.

As for working temp of the motor I recommend no more than 150 deg c. I found that at 170 the piston can easily pick up on the liner just below the exhaust port (the hottest part of any two stroke) and the expense to repair and downtime is a pain.
the best advice is to regularly remove the plug and check the color. Aim for a light brown plug tip. If it is black too rich, and white too lean. Any lean running is really bad and will kill the motor in minutes. Alway err on the rich side for peace of mind.

I hope this helps. Gassers are a real learnig curve, but worth the effort in the long run.

Cheers Keith

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Keith,

Thanks a lot for your reply, the motor temperature is now controlled, there was problem with the muffler.

Regarding the head speed is good to know that i could have problems with the align governor and that the best speed will be arround 1750 rpm.

My question is the following, i have my head speed arround 2000 rpm, my throtle curve is 0, 30, 50, 70, 90, the picth curve that i have is:
Normal: -3, 0, 5, 9, 12
idle 1: -5, -2, 0, 6, 12

The problem that i have is that when i have the heli on normal or idle 1 and i apply full throtle i fell that the heli doesn't climb in a fast way, also, if i change from in idle 1 from pitch -5 to +9 or more it takes a while to start climbing.

Is this normal for gassers? i have seen some videos and it seems that their machines have more power.

I am about 3000 meters over sea level.

I have a trex 700 with a Zehoah G290-RC and RJX muffler, it's a flybar heli, the governor is not set yet.

Reagrds,

Francisco Morales.

Hi again Francisco,

Lets see if I can help you a little more. If you are still on curves and you say your headspeed is 2000rpm, can I ask which pinion you are using 17 or 20 tooth?
Depending how you have set your throttle linkage I would think you will be at full throttle at 80 percent. ( a petrol engine trait)
Your max pitch is possibly a little too high, try reducing it to 10 degrees. Does the motor bog when given full throttle? Pehaps your 12 degees pitch is too much if you reduce it then it may climb better.
If you have a standard motor it will never produce the power of a tuned hanson or toxic one, as often seen on video.
Remember the weight of a gasser will reduce performance and a standard motor only produces a couple of bhp. You need to find the best compromise between power and torque. Reducing your rpm may result in a better climb rate as you find the "power band" of the motor. Sometimes less is more.
As for your idle up and normal pitch range, the ones you quote do not really make sense to me. If you were to switch modes while flying the heli would jump, I do not like that idea. I usually set my pitch curves identical and just reduce the negitive value in normal mode.

Mine would be something like norm -5 -2 0 5 10 in degrees.
idl 1 -10 5 0 5 10
idl 2 -10 5 0 5 10
or in the radio norm 25 inh inh 0 inh inh 100
idl 1/2 0 inh inh 50 inh inh 100

This way when flying the only change when I selected idle up would be in headspeed with no jump in pitch when hovering or flying upright.

throttle curves are norm 0 15 25 30 46 70 100
id 1 100 70 46 30 46 70 100
id2 100 70 46 30 46 70 100

I do rely on my governor ( gv-1) a lot, but find this works for me.
I recommend the 17t tooth pinion on the helibug 700. I found with the 20t the headspeed is too high at the optimum engine speed.
The standard 26 cc zenoah seems to like 9 to10,000rpm, but the trm 270vx I have now fitted is happy up to 12,000rpm.

I hope this helps, Keith

Here is mine while still running rich.

http://www.youtube.com/watch?v=PpMVuRIcX7M