Moki 1.8 performance
#1
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From: Canton,
MI
I ran my Moki 1.8 w/ 5% nitro Sig fuel (10% castor 10% synthetic), OS #8 plug, and have rpm and thrust reading.
APC 18x6W: 9400, 19.1 lb thrust
Pro Zinger 18x8: 8500, 17 lb thrust
I measured the thrust with a digital force gauge by hooking the hook no the gauge to my tail wheel vertical axle.
My plane is Kange Cap 120, weighing 13.5 lb w/ the Moki. A little heavy I feel. But I have a WM female pilot w/ hair, 3 1/4" wheels, 3/16" axle, wheel pants, large volumn BCM Pitts muffler. Could get down to 13 lb if I go ugly.
APC 18x6W: 9400, 19.1 lb thrust
Pro Zinger 18x8: 8500, 17 lb thrust
I measured the thrust with a digital force gauge by hooking the hook no the gauge to my tail wheel vertical axle.
My plane is Kange Cap 120, weighing 13.5 lb w/ the Moki. A little heavy I feel. But I have a WM female pilot w/ hair, 3 1/4" wheels, 3/16" axle, wheel pants, large volumn BCM Pitts muffler. Could get down to 13 lb if I go ugly.
#5
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From: Canton,
MI
I pinched one of the BCM Pitts muffler's exhaust stack to give more back pressure. I ran it again today with Wildcat 5% fuel. Peaked at 8700 rpm w/ Pro Zinger 18x8.
#7
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From: Canton,
MI
ORIGINAL: JoeAirPort
I get 8400 on a Bambula 18x8. It peaks out at 8700 then I richen it up.
That's Morgan FAI fuel, K&B 1L plug.
I get 8400 on a Bambula 18x8. It peaks out at 8700 then I richen it up.
That's Morgan FAI fuel, K&B 1L plug.
By the way, I tached the Moki 1.8 w/ Pro Zinger 18x6 on 5% Wildcat fuel, peaked @ 9200 rpm.
#8

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From: Sarasota FL
Homebrew:
Racing Methanol
0% Nitro
22% oil, consisting of 75% Klotz synthetic/25% SIG Castor
Glow Plug - K&B 1L
Muffler - Bisson Pitts - both pipes fully open, using muffler pressure
Engine completely broken in
Peak Readings - TNC Tach
19x8 MenzS - 8800 rpm
18x8 Zinger standard (not Pro) - 8900 rpm
Racing Methanol
0% Nitro
22% oil, consisting of 75% Klotz synthetic/25% SIG Castor
Glow Plug - K&B 1L
Muffler - Bisson Pitts - both pipes fully open, using muffler pressure
Engine completely broken in
Peak Readings - TNC Tach
19x8 MenzS - 8800 rpm
18x8 Zinger standard (not Pro) - 8900 rpm
#9
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From: Melbourne, AUSTRALIA
Brand new Moki 1.8 using FAI fuel (80% meth + 20% BeNol) spinning a Bolly 19x8 CF prop delivers a solid 8100rpm and peaked to 8400-8500 rpm on the bench after 2Lt break-in. Wow this engine delivers some thrust and it's so easy to start on a back flip provided that Moki plug has to be cranked up to about 4amps. On the bench it's a dream, we'll see how it goes in the plane (GSP/CMP Katana 72") this weekend.
#10

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From: HOUSTON
Anybody ever notice a sucking noise when priming their Moki? I have a 210, and two friends have 180s. They all seem to do it. Either gone or much less when hot.....sucking air through front bearing? One of the 180s has new bearings in it, still does it.
thanks,
jp
thanks,
jp
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From: Melbourne, AUSTRALIA
Yes I noticed that noise and the unhealthy looking dribble of fuel that flows from the front bearing when the engine is too wet. It doesn't seem to adversely affect the engine's performance. The Moki is one of the best (ease of starting, power, idle, transition) engines I have ever had the pleasure of using. I guess that we just put up with a little mess and that sucking sound from the front bearing.
On a different topic, are people using the Moki gold plug that comes with the motor? I found that it requires a lot of current (4amps) to get the engine to fire - not a bad thing just an observation. Probably because the actual element is quite a bit thicker than my usual OS#8. The Moki plug is giving me very reliable long idle periods (tested to 5 mins) with instant transition to full throttle, plus good RPMs (over 8400 on Bolly 19x8) on 0% nitro. I hear so many people prefer the OS FS plug - why?
On a different topic, are people using the Moki gold plug that comes with the motor? I found that it requires a lot of current (4amps) to get the engine to fire - not a bad thing just an observation. Probably because the actual element is quite a bit thicker than my usual OS#8. The Moki plug is giving me very reliable long idle periods (tested to 5 mins) with instant transition to full throttle, plus good RPMs (over 8400 on Bolly 19x8) on 0% nitro. I hear so many people prefer the OS FS plug - why?
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From: Whangarei, NEW ZEALAND
Hey guys,
Not sure if this thread is still going..... but i need some help, Just running in my Moki 180 with a 20x10 wooden prop, its to big and i am going to an 18x8 (seems to be popular)
I was wondering - does a mezjlik 18x8 have the right size hole to fit onto a Koki shaft - or does it need to be reamed out?
Cheers
RJ
Not sure if this thread is still going..... but i need some help, Just running in my Moki 180 with a 20x10 wooden prop, its to big and i am going to an 18x8 (seems to be popular)
I was wondering - does a mezjlik 18x8 have the right size hole to fit onto a Koki shaft - or does it need to be reamed out?
Cheers
RJ
#21
O.K. quick question, anyone have an opinion or experience on mounting orientation w/the 1.8. Upright, horizontal, or inverted. I need it inverted on the plane but horizontal could work with a little cowl cutting.
Thanks
Dean
Thanks
Dean
#22

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The only operational difference is in starting the engine. It is easy to prime when the engine is mounted from upright to laying on its side. Inverted mounts are impossible to get primed for a simple bump start, if a starter is used then it makes no difference.
#23
Thanks, I wasn't sure, I hve had ASP's that would almost refuse to tune in an inverted configuration and just wanted to ask someone who had a Moki if they were like that.
#24

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It needs a 10 mm through-hole with a 12 mm ream at the rear of the prop, 5 mm deep. Or you could just ream it 12 mm all the way, I didn't like doing that so it could fit other engines. Standard bore on almost all large props is 10mm.
The Mezjlik will fit fine but you will need a 12 mm reamer to make it fit the aft part of the prop bolt. You want about 8400 RPM's with that engine. I used a Bambula 18x8 and it really pulled the plane hard in verticals. The Mezjlik will likely turn around 9000 since the paddle area is a lot less than the Bambula. Not a bad prop. You could save a bunch of money and just get a wood Airwild NX, Menz, or JFX 18x8 prop. They all would run well on that engine and are much lighter than the CF.
The Mezjlik will fit fine but you will need a 12 mm reamer to make it fit the aft part of the prop bolt. You want about 8400 RPM's with that engine. I used a Bambula 18x8 and it really pulled the plane hard in verticals. The Mezjlik will likely turn around 9000 since the paddle area is a lot less than the Bambula. Not a bad prop. You could save a bunch of money and just get a wood Airwild NX, Menz, or JFX 18x8 prop. They all would run well on that engine and are much lighter than the CF.
ORIGINAL: kainisrj
Hey guys,
Not sure if this thread is still going..... but i need some help, Just running in my Moki 180 with a 20x10 wooden prop, its to big and i am going to an 18x8 (seems to be popular)
I was wondering - does a mezjlik 18x8 have the right size hole to fit onto a Koki shaft - or does it need to be reamed out?
Cheers
RJ
Hey guys,
Not sure if this thread is still going..... but i need some help, Just running in my Moki 180 with a 20x10 wooden prop, its to big and i am going to an 18x8 (seems to be popular)
I was wondering - does a mezjlik 18x8 have the right size hole to fit onto a Koki shaft - or does it need to be reamed out?
Cheers
RJ
#25
Hi guys, Just looking for some feed back.... I have just been running a Moki 1.8 for the first time (for me) the engine came with a nice 1/5 scale Spitfire model I purchased second hand with plenty of flights already logged. Anyway after running up Moki to check performance all seems just fine and ready for flight, But I just noticed some for/aft play in the crank, I would say approx .5mm approx maybe a fraction more play, there does not appear to be any lateral play at all just slight for aft play with prop and spinner on correctly and tight enough...... does this indicate a bearing is worn out??? any advice welcomed.
Cheers- Marty
Cheers- Marty



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