: Spekky problem (pipe, engine, tank)

12-04-2010, 10:07 PM
Hi guys,

I am tottaly new to gasser heli, and spekky is my choice. Love this heli at the first sight. I flown rappy50 before, but spekky is tottaly different. Lots of people says gasser setup is different.

Ok, here's the problem I found so far:

1 st flight.
Melted zenoah air filter at the first flight, pipe come off, and seized the engine. Luckily I could save her, it was my first auto. The fuel mixture was 25:1. I believe it was my mistake by close the air vent on tank :bang:
Then I went back home, check the heli and order parts. It was 26cc Zenoah barrel, piston+ring, and pin.

2nd flight.
During the break in I use same mixture but with petroleum based oil. H and L needle were 1.5 turn from full close. Start the engine and it runs great (not hover yet). But it vibe more, I think because of the new engine parts. I felt worry a bit, but really want to fly this beloved heli. Went to a field, here the real problems are. When it hover the pipe went off again! landed the heli tighten it up and hover again. At certain point the engine is getting choked then rev up unstable, just like cough. The tail shake violently. Went back home. I rebuild the pipe (put heaps of red thread lock), rebuild the carb, totally disassemble and clean up. Check the sparkplug and it was matte dark red brick color. Then put them back again.

3rd flight.
Same problem just in different day.

Could anyone help me with this? What actually happen on the engine? I just order WT813, hoping it will help.

How to make the pipe stay forever in the engine?

and how to reduce the vibe, I saw the fuel is foaming. Isn't it dangerous when it fly? I haven't prepared for another auto.

Thank you guys.

12-04-2010, 10:42 PM
Is it a modified 260 , or a standard zenoah ? the std one is known to shake, especially when new ..

813 is a boat carb , best for helis is a 643 or 644 , , identical but 644 has a choke..

What muffler are you using ? Dont use threadlock , it becomes a lubricant when it gets hot ; use an RTV silicon sealant on the faces .. tension the mounting bolts when the muffler is hot..

you need to set the throttle so that the carb butterfly is approx 1/3 open at the hover throttle position , with the 643/644 at least!! a thr curve of 0 , 10,15, 26, 35,100 isnt unusual , in NORMAL mode .. Don't use a governor untill the motor is run in , and you have the throttle sorted properly..

I run 32:1 fuel mix , unleaded petrol .. 1.5 turns out is a tad rich, especially at a 25:1 mix , but check the carb butterfly/throttle setup first..

And get rid of the one way valve on the tank breather , leave it open ...

Where abouts are you ???

And I agree , the Spectra G's are AWESOME !!! but definitely different!!

13-04-2010, 10:02 AM
Hi Peter,

It was bh hanson before, but after weld the piston and barrel I changed the broken parts with standard zenoah.

I will stay on 643. I'm using century v3, but thinking to get another pipe. What is your suggestion?

About the pipe, so I have to clean the excess thread lock. re-tighten when its hot and put RTV sealant on the face do you where the hex key in?? Is that correct?:D

How to set the throttle properly? Do you mean the linkage? I don't have idea about it. At the moment my throttle crve is 0, 20, inh, 37, inh, 60, 90, with exp on.

I'm living in Melbourne.


14-04-2010, 08:48 AM
I had a similar hassle with a Hanson 26 , the exhaust port cracked off , std Zenoah parts fixed it ; been good ever since...

I have century V3 mufflers too , I use a DDM copper gasket between the muffler and cylinder , so far its working! With a very thin coating of RTV on the faces , then retightened when hot ..

Throttle /carb setup is very important, the G should hover on the main jet , just past the transition point, which is approx 1/3 of the butterfly opening..

Do you hover with throttle at 1/2 stick , or at 3/4 stick position ?

Set up the throttle end points so the carb lever just doesn't bind at both ends , with as close as possible to the same travel both ways , then put the throttle stick at hover position , adjust the curve till carb butterfly is approx 1/3 open , set high throttle point to 100% and ramp up the throttle curve from idle to the hover setting.
both needles at 1.5 turns out is OK to start with , you'll prob have to adjust the idle throttle position initially..

If you're prepared to travel to the Latrobe Valley club ,( Moe ) , I can give you the phone # of a bloke there who can save you lots of time and $$$$..

14-04-2010, 07:35 PM
Thank you Peter, I will follow you sugestion. And it would be great to see someone that could help me in Melb, what is his contact number? I would like to arrange some time to meet him. One more think Peter, what is the best setup for the pitch curve?

Can't wait to fly this heli :flame:

14-04-2010, 08:03 PM
Re the pitch , I run +-11 deg, 0 deg at centre stick ; on mine , with 710 blades on the Extreme head , 690's on the Tempset head

Sent you a PM with the contact info...