rrTV-PHOTO   New HD TV
HOME   rrTV-PHOTO   GALLERIES   MY GALLERY   HELP-FAQ
myHOME PM pmRR MEMBERS 550 ONLINE 20 EVENTS SEARCH REGISTER  START HERE
 
1 page1391 viewsPOST REPLY
Thunder Power RC . Mikado Modellhubschrauber . GrandRC

.
.
Robbe Cuatro - Millennium - Nova - Dyna-X > Cuatro gear ratio and head speed help
 
 
kima
Senior Heliman
Location: Wellington, New Zealand

Hi,

At the moment I am using the standard gear ratio which is 8.89 and I am using MAH 850 symmetrical blades and the motor is a G231. The helicopter will be used for Aerial photography.

If anyone is using a similar set up please can you share what you have found to be a good stable head speed and the gear ratio you use?

I also have a Hanson modified G26 on its way and need to find out what the ratio to use and what the best head speed to run with this motor.

My fuel mixture is 40:1 using a high quality synthetic oil motorX racing oil.

K R Attwell
www.PhotoHigher.co.nz
06-03-2007 Over year old.
HOMEPAGE  
 
 
RCMarket
Key Veteran
Location: Belgium , Europe

ratio

Kim

when you say "standard: you mean 23t supplied as standard in the Cuatro kit? if so, its not ok, because with Gas you need to increase the clutch bell size, choice is 25-27t.

Fuel, i would use 3-5% oil, e.g 1:20-25. to make proper lubrication.

Not sure what muffler will be used, but the new Zimmermann gas muffler is perfect..

Alex (Formerly Known as Futurac )
06-03-2007 Over year old.
 
 
kima
Senior Heliman
Location: Wellington, New Zealand

Thanks Alex,

what is the better ratio to go for, if anyone has a Cuatro with Zenoha G231 or 260 please can you tell me what head speed you are running, fuel ratio and gear ratio or what tooth clutch bell you are using.

Alex - this is getting very confusing some say 20-25:1 is OK for running the motor in and then you should be using from 40-50:1 some use even less. This motor has been well run in and i am using a Zimmerman muffler.

Please can somone help me out this motor is really driving me nutts, i just cannot seem to get it to run smoothly. If i do a small climbout as soon as i start reducing the pitch to getthe helie back down the motor starts to splutter and now and then cuts out. I think i will post this under the gasser motor section.

Any advice will be much appreciated

Cheers

K R Attwell
www.PhotoHigher.co.nz
06-04-2007 Over year old.
HOMEPAGE  
 
 
RCMarket
Key Veteran
Location: Belgium , Europe

Gear

Kima

with 26 Zenoah and 850 i would go for 24-25t, exact pinion is a bit difficult to predict
you will run little less head speed whtn with 810 any way.

oil, i beleive you located in hot weather place, i would run more oil rather then less.

Alex (Formerly Known as Futurac )
06-04-2007 Over year old.
 
 
juha76
Heliman
Location: finland

Kima

I have a hanson 3d max (g26)and zimmermann muffler in my cuatro. I use synthetic honda hp-2 oil in 32:1 ratio and so far no problems with the motor.

I dont know my headspeed because i dont have a tach,but i have
800mm blades and the standard gearing. I might try 25t clutchbell to get more headspeed without overspeeding the engine.
06-04-2007 Over year old.
HOMEPAGE  
 
 
Jarno
Veteran
Location: Finland

Kimberley,

I will try to answer your questions later today if I have time enough. We will get your engine to run good for sure!

Adding more oil will only make petrol engine to run hotter! It's definitely NO, NO. Oil is not used for cooling on a petrol engine like it's used on glow engines where oil carries away heat and dissipates it. The more fuel and less oil is better with petrol engines. EDIT: I didn't read Alex's post very carefully so I didn't notice what percentage of oil he was suggesting so it will not do any harm. Anyway too much oil will lead to deposits on the piston and cylinder head. And the piston ring can get jammed.

Cheers
06-04-2007 Over year old.
HOMEPAGE  
 
 
Qrrambero
Veteran
Location: San Francisco / Bay Area

Jarmo, your wife to be is going to be upset if you keep helping us.
You should be getting ready for the wedding and honey moon.

Ae
06-04-2007 Over year old.
 
 
kima
Senior Heliman
Location: Wellington, New Zealand

Congratulations Jarno – good to hear!

I will wait to see what you are currently running, head speed etc

K R Attwell
www.PhotoHigher.co.nz
06-05-2007 Over year old.
HOMEPAGE  
 
 
Coolrunnin
Veteran
Location: Manchester U.K.

Kima -

I'm running the stock 8.88:1 ratio on a G231PUH (standard engine) and have used it for aerial photography/video. I run a governed 1320 headspeed with one thin damper shim on each side of the head block. This gearing gives 11700ish on the crank and runs very smoothly indeed with only 800mm (NHP) blades. Muffler is a Zimmerman Gas Q-pipe with custom header. BTW even at 1320rpm with the 800s this heli lifts my very basic 3Kg cam mount almost like it's not even there!

With 850s I would expect that the stock gearing will be absolutely fine on the 231 (assuming you fly lower headspeeds).

Just my 0.02
06-05-2007 Over year old.
 
 
kima
Senior Heliman
Location: Wellington, New Zealand

Thanks,

I have discovered that the carb manifold is badely warped and the steel bushes are pulling through, so i am sure this has been leaking and causing havok.

I am waiting on a Z-RC alloy manifold which i hope to recieve soon and then i will give it another go. I also need to get used to turning those blades and being able to see them go round. Ithink this is where i have been going wrong as well trying to get the motor to run smoothly with a head speed of around 1450 1500 - not good!

I will let you know how i get on.

K R Attwell
www.PhotoHigher.co.nz
06-06-2007 Over year old.
HOMEPAGE  
 
 
Jarno
Veteran
Location: Finland

Quote 
Jarmo, your wife to be is going to be upset if you keep helping us.
You should be getting ready for the wedding and honey moon.

Sorry for delayed reply guys, but my wife to be keeps me busy planting roses all over our garden and not having much time for helicopters.

Thanks Kima! I just sent you an email with some tips, even though you've most likely found the reason for poor running. Air leak on the carb will show as lean running engine for sure.

I would not be much worried about the gearing and head speed. Now I use std. gearing with success on mine. I can easily run up to 1550 on the head without any problems, even though it sure overrevs the engine. I will sure change to lower gear ratio to get more rpm on the head on my Cuatro if I decide to use it for contest flying, but at the moment I'm happy with the standard gearing. It suits just nice for general flying and aerial video/photo stuff.

I will get an new Webra 150Hi petrol engine for testing soon and I believe that I will change to lower gearing then. Webra will be better suited for contest flying as it's a lot lighter and has more power than Zenoah engines. I have an Webra 91Hi on my Dyna-X and it's way smoother than my Zenoah so I really look forward testing this new one too. If it turns out to be great then I will definitely use it on my aerial video ship too. But will see how it goes. Now I'm happy with my Zenoah, but if there's something even better available then I'm always interested testing it.
06-06-2007 Over year old.
HOMEPAGE  
 
 
Coolrunnin
Veteran
Location: Manchester U.K.

Jarno - I'll be interested to see about the longterm reliability of the Webras vs the Zenoah. The only concern I have is how durable they are compared to the nicely overbuilt Zenoah
06-06-2007 Over year old.
 
 
Jarno
Veteran
Location: Finland

Here is the beast. I really look forward testing it. Time will tell about long term durability of the Webra gas engines, but I'm pretty comfortable they will do well in that department too.

There's also a pic of a Webra made engine mount for Cuatro.

06-10-2007 Over year old.
HOMEPAGE  
 
 
Coolrunnin
Veteran
Location: Manchester U.K.

Looks good ... and a lot smaller than the Zenoah. Keep us posted on how this goes in the Cuatro for sure. If it is significantly smoother than the Zenoah and lighter as well then I would be very interested in trying one.
06-10-2007 Over year old.
 
 
sharam
Elite Veteran
Location: Northern California

Jarno,

Did you have a chance to run the new Webra?
07-17-2007 Over year old.
 
 
Jarno
Veteran
Location: Finland

Nope not yet. I should be walking the line in church in less than two weeks so preparing of the wedding has taken most of my time. I really look forward trying the 150i as soon as I have managed trough all this.

Cheers
07-17-2007 Over year old.
HOMEPAGE  
 
 
limced41
New Heliman
Location: france

Hello,
I'm french boy
What think you about this engine?
Have you experience in fly about this ?
What max temperature ?
And better fuel ? In france have 95 or 98 octane gas.
I have a T-rex 700 and I modify this for put in the 150hi webra.
I've change so the pinion 20T (origin) at 23T for modify ratio and allow 1950rmp max at 100%.
Sorry for my bad english!
Cordialy
Cédric
10-27-2008 12:18 PM
 
 
1 page1391 viewsPOST REPLY
CanoMod . Futaba-RC . A Main Hobbies

.
.
Robbe Cuatro - Millennium - Nova - Dyna-X > Cuatro gear ratio and head speed help
 PRINT TOPIC Advertisers 

Subscribe to This Topic

Sunday, November 23 - 2:01 pm - Copyright © 2000 - 2008 runryder.com | email | link to rr | runryder needs cookie