Moki 2.10
 

8100 rpm (on new engine after 1 gallon)

Using an APC 20x8
Original Moki plug
5% PowerMaster Fuel
75F Air Temp
approx 65F Dew Point

Mounted on Aeroworks Edge 540 29% kit

Moki 2.10
 

Muffler??

Moki 2.10
 

Bisson Pitts style

Engine still running great. Having tached it lately.

Moki 2.10
 

Excellent numbers!

Thanks.

Moki 2.10
 

7500 on a 20X10 Zinger with 0% Nitro home brew. Bisson pits muff. Well broken in on a TF P51.

Moki 2.10
 

Bambula 20/8 prop
pitts muffler, Bisson
No nitro, 15 % oil

6600 RPM

Motor is still being broken in so I hope for improvment.

tony

Moki 2.10
 

Tony ,

That number sounds real low but I do know it takes many gallons of fuel to break in the moki. Give it time and try different manufactures of props until you find what works for you. Also I believe Moki recommends 20% oil. Maybe this is also an issue. All I know is that you have one bear of an engine. Hang tight.

Jim

Moki 2.10
 

JIm;

Thanks for the encouragement. I have two of the Moki 180's and they are both stronger then the 210. Of course the 180's are old and the 210 is new Sooooooo I am being patient.

tony

Moki 2.10
 

20% oil will choke a Moki, After a decent break-in run 12-14% oil.

Moki 2.10
 

Has any one tried a larger diameter prop? I'm using a Mejzlik 20 x 10 on my Moki and it turns about 7500 at sea level with no nitro. The plane flies okay, but I want more thrust and down-line braking. With the 20 x 10 I have way more speed than I need and the throttle response isn't great. I believe the Moki 2.10 reaches peak torque at about 7500 rpm. That's where I want to be at full throttle on the ground. If you've used a larger diameter prop, could you tell us what it was and how it worked (full throt. rpm on the ground)? Thanks.
Woody in Maryland
P.S. I'm now running a Perry Pump. It seems to help with consistent mixture no matter the plane's attitude.

Moki 2.10 Setup
 

You shouldn't need a Perry pump. The main thing with a Moki running consistently is fuel draw, and like the directions recommend, if you use large ID fuel line from the CLUNK to the carb you won't have any probs. Also, make sure the fuel tank height is per the instructions, especially if you are having consistent running problems at various attitudes.

Moki 2.10
 

RH, Thanks for the information. Everything was set up correctly before I installed the pump - large ID tubing from large ID clunk to carb and the tank was positioned correctly. The engine used to go lean on up-lines, so I had to richen the main needle to prevent this. I then had a crappy midrange. The front edge of the tank is 14" from the back of the carb. With the pump, the mixture settings don't change and I have much better throttle control. What prop do you use?

Moki 2.10 Prop
 

I'm using the APC 20x8. Others have used the APC 20x10 with good success too. See earlier posts for my tach readings. With the 20x8 vertical is unlimited, but more importantly straight line speed is good for IMAC. I'm in San Antonio, Texas ~400(?) above sea level with usually high dew points and high air temps.

Moki 2.10
 

Moki 2.1 on Omega 10%, OS F type plug and 20x10 Menz 'S' prop.........6800 rpm max after two gallons. I'm assuming these numbers will improve with further running! RollingHoover FYI ..... correction, San Antonio is ~650 feet MSL.

:cool: JMW

Moki 2.10
 

Guys, I tried a Bambula 20 X 8. Compared with my Mejzlik 20 X 10, I have much better down-line braking (much better) and vertical up-lines are much stronger. On the ground I got 7020 rpm. The temp was about 90 deg F with very high humidity (70%?) at sea level.

Moki 2.10
 

Staggerwing;

How much stronger is your vertical with the Bambula 20/8?

tonyc

Bambula 20x8 prop
 

Staggerwing, what airframe is that in and what is the weight?

jmw

Moki 2.10
 

tonyc, what prop are you currently running and what airframe/weight are you using? Is that 2.1 turning up any more rpm as you get more run time on the engine? I am hitting about 6800 max on a Menz 20x10 after about 2 gallons.

jmw

Moki 2.10
 

I fly a Lanier 80" Cap 232. I'd guess it weighs 16+ pounds. The Bambula 20 X 8 noticeably increases the vertical up-line pull, but I won't try to hover - not enough excess thrust for that. It will climb straight up a few hundred feet (400-500?) before it runs out of steam if I enter the pull-up with speed at full throttle. To me, the plane flies very scale-like. In fact, a guy at the field used those words to describe its flight characteristics. The plane is way too heavy to hover with any authority. The biggest difference is in the braking. This prop really slows it down. For an aerobat, speed isn't necessary. The Bambula pulls the plane well. Woody

Moki 2.10
 

At 16 1/2 lbs you'd think that Moki would blast that CAP out of a hover but I am starting to think all the hype about the 2.1 putting out 25 lbs+ of thrust on a 20x10 prop is a lot of hype. I have mine in a 14 1/2 pound GP Patty Wagstaff Extra 300 and although it has good vertical it's still not where I thought it would be. A quick check with a digital scale showed just under 20 pounds of thrust with a 20 x10 Menz prop. To be fair to Moki though this was after only one hour of run in time so it may improve. What are you guys getting for thrust?

jmw

Moki 2.10
 

I agree. Although I have no way to measure static thrust, I'm sure I'm not getting 25 lb. According to Gerard's information, the engine should be proped to run at 7000-8500 rpm on the ground. Does this suggest the engine achieves maximum torque within that range? I'd like to do some more experimentation, but at $15+ per prop, I'll hold off for now. I have enough performance to do IMAC type of maneuvers and I now have down-line braking...something I REALLY wanted. Ideally, I'd like to dyno the engine to see exactly where it reaches peak torque and then prop accordingly. I bought my engine used on the plane, but it runs and idles so well that I feel it was broken in properly. I wonder if I could get away with something like a 22 X 6? Do you like your Patty? I saw a full-scale Extra fly for the first time last weekend and fell in love with them. Try a 20 X 8 in the Menz and see what you think. I never noticed a change in top speed (something I rarely do anyway) after changing to the 8 from the 10.

Moki 2.10
 

Mejlick 20x9 = 7800rpm
1.5 gallons of byron 0% through it.
K&B1L Plug.

Bambula 20/8 6400 rpm
 

I just started the 4th gallon of fuel.

No nitro, 18 % oil (added some more castor)
91 degrees, 53 % humidity

6400 rpm. :confused:

Flying an Ultra Hots, weight is 15 lbs.
Vertical is good but not unlimited.

I think I am about 800 to 1000 rpm low. thats a lot of ground to make up in the next few gallons.

I will try a Bambula 18/8 prop to get the rpm's up for a couple of flights.
I also have a Moki 20/10 prop on its way to me.

But so far my Moki 180 is better.

tonyc

Propped for a warbird
 

I have an APC 18x12 on a Moki 2.10 turns 8500rpm on the ground with an ambient around 85degrees. Using Performance Plus 5%nitro with 20% oil and OS F plug. Large fuel line and no pump.
This combo powers a WM GS P-51D at 16# 12oz
Have about 3 gallons through it so far.

18/8 Bambula 7600 rpm
 

I just did a couple of flights with an 18/8 Bambula. So far all I am getting is 7600 rpm on the 18/8. I even tried an APC 18/6 wide prop, the Moik hit about 7860 rpm. :(

My Moki is off by about 800 to a 1000 rpm.

I have a Moki 20/10 prop on its way to me. This is the Gold standard prop for this motor. With this prop I should see 7500 rpm. No Way, I would say.

After I try this prop, if the rpm is low, I will box up the motor and let Gerard Enterprise have a look at it.

I have two of the Moki 180's and both are stronger then the 210.

tonyc

Moki 2.10
 

What muffler are you using? I get much higher RMP. I will be trying a bambula 20/8 next weekend. I will let you know what I get.
The only thing I did is I cut about 1/2" off the ends of my pitts muffler.

Moki 2.10
 

It does sound like your's is off from the rest of ours. My 1.80 will turn most 18/8's at 9K. A friend's 210, about 1/2 gal through it , turns a MenzS 20x8 at about 7200 and it is on the rich side.

Moki 2.10
 

My Moki has the Pitt's muffler with the exhaust tube ends cut off.

h82crash; My Saito 180 turned the APC 18/6 wide at over 9000 rpm. The Moki 210 turned this same prop at 7860. Now thats low.

I just took the Moki off the Ultra Hots. I will try a couple of bench runs and then send it back.

The confusing thing is that the Moki does every thing right. Easy starts, even when hot, good idle, good transition, just weak on the top end.

Hope to get to the bottom of this problem soon.

tonyc

Moki 2.10
 

I'm hitting only about 6600 rpm on Omega 10% and the Menz 20x10 after 3 gallons but the performance in my 14 1/2 pound Patty Wagstaff Extra is breathtaking. I think I am going to give the Mejzlik 20x10 a try. TonyC, you have a sick engine on your hands judging by your numbers with the APC 18x6W, my Saito 180 turns that same prop much faster...send that engine back to the distributor.

jmw

MOKI LIVES!
 

Excuse the excitement but I now have bragging rights.
Here it is.

Moki Ultra 20/10 prop 7660 rpm on no nitro fuel.

Saturday after I flew the Hots with an 18/8 Bambula prop and having weak performance, I decided to call Jim Gerard. Let me tell you he is a great guy to deal with. The short story is that I was doing every thing right, I just had a sick Moki. I told Jim I had a Moki Ultra on its way to me and I would run one more test. The Moki Ultra 20/10 is the gold standard and should hit 7600 rpm.

I was so positive that my 2.10 didn't have a chance to do this that I took the motor out of the Hots. I even took out the tank. Put the motor on a test stand and waited for the prop to come in.
Tuesday after work, the prop was in my mail box. I drilled it out, put it on the Moki and hurried to start it before the rain came.

I flipped, I flipped, I flipped, did I mention that I flipped that stupit prop for about 15 minutes without so much as a cough from the motor. I mean I was mad, I flew this motor at least 40 times and its a "starts on the first flip Moki" you know! its just not a problem to start. Well the rain came and I had to stop. Later that night it came on me. The Moki was taped for a Cline regulator and the vent was open. DUH!

Yesterday, I hooked the Cline regulator back up, flipped the prop and the motor was running. Full open on the carb, grab the tach and saw 7660. Thats the magic number that Dave Gierke talked about when he tested the Moki 2.10 for MAN. That motor was humming. :D

Oh by the way the Moki Ultra prop is beautiful, best looking prop I have ever seen.

So what was wrong before? Well, I don't know. My best guess is that some where I had a fuel restriction, perhaps a partial kink in the line. All I know is on the bench it did what it was suppose to do.

Love that Moki, and the Ultra prop.

tonyc

Moki 2.10
 

Congratz. I have a bambula 20x8 that I will be trying this weekend. I also bought a digital fish scale so I can get a thrust reading. I only have about 1.5 gallons thru it and I know that it runs better every time I start it.

What size fuel tank are you guys using?

Moki 2.10
 

Crash90

Post your numbers when you get them.
I think that 7200 is the expected # on the 20/8 Bambula.

I use a 24 oz tank, but I will be swithching to a 20 oz tank. When I get my Hots re-built.

tonyc

Moki 20x10 Prop
 

tonyc,

Where did you get your Moki 20x10 prop? How much? How about a pic of it?

Got it here on RCU
 

I bought the prop here on RCU. Brand new for $18 plus I paid $4 to get it shipped.

I am not yet digital so no picture. The prop looked like a piece of expensive maple furniture, the finish was that good.

I don't know if Moki props are still available. Frank Tiano no longer handles them.


tonyc

Fuel Tank
 

I'm using a 40oz. Dubro in my giant scale P-51. I usually run flat out for 13 minutes then still have time to slow it down for a few laps then land. This leaves me with 1/4 tank for emergencies......

RE: Fuel Tank
 

My last post was lost.

Moki 210
1.5 gallons of fuel
Byron 0%
Bambula 20/8
K&B1L Plug
Bisson Pitts Muffler with ends cut.

Cold 77-7800 rpm 18lbs thrust
Hot 75-7600 RPM 16.5lbs

Thrust was measured with Rapala 50lb digital scale. Wraped rope around tail, hooked it to the scale and throttled up.

RE: MOKI LIVES!
 

Hi Guys:

I have two Moki's and the 2.1 is definitely stronger. I am running a Moki 20-8 prop in a 1/3rd scale Pitts @ 15-1/2 lbs. and it turns 8500 on the ground using Byron 5% with 18% oil. I have unlimited vertical and can pull up out of a hover with easy. More than enough power for this airframe. My 1.8 is in a Hanger 9 Cap and what a combination. Knife-edge loops aren't a problem with a Moki 18-8 prop.

Scale Speed

RE: MOKI LIVES!
 

A couple of quick questions to the Moki experts:

1. Does higher nitro increase rpm/thrust with the normal IMAC style props used on this engine? I am running 10% nitro, have not tried lower or higher nitro to check the effects. with fuel costs what they are, I want the highest possible cost to benefit ratio.

2. Bisson lists two muflers for this engine in the Pitts style. One they call the high volume style and the other they call the low volume style. Does anyone know the difference in power output between the two???????

3. I have the low volume stlye Bisson Pitts muffler, what is gained by cutting off the muffler tips like some of you guys are talking about on this thread?

4. I have 4 gallons through this engine so far and I am taching 6660 rpm with the Menz 20x10 prop on 10% Omega fuel. You guys are getting way more rpm than I am. I'm starting to believe I got a dud or someday stuffed a shop rag in my intake. It could also be the Menz prop is less efficient. In defense of Menz and Moki, the combination is pulling my 14 1/2 pound Patty Wagstaff Extra straight up out of sight without even slowing down. Also the downline braking is awesome, it almost stops in midair when you chop throttle. Anyway, has anybody else tried the Menz on this engine, I want all the thrust I can get out of this critter.

5. Where can I get the Moki 2.1 prop everbody is talking about and how much?

jmw

RE: Moki 2.10
 

John,

Strange how low your rpm's are, but at least the flying perfomance is there.

I just tach'd mine again early yesterday:

7800 rpm (needle valve slightly rich). Peak is 8,000 rpm.
Using an APC 20x8
L1 plug
5% PowerMaster Fuel
85F Air Temp
approx 69F Dew Point (before the rains came...)
Bison Pitts Style muffler

I'm not sure of the volume differences that you mention, but I'll check for you tonight.

When are you flying that plaen. I would like to see it fly. Ben

RE: Moki 2.10
 

Hi Ben, I flew last night over at Bandera, it's a bit tight over there but close by the house, will try to get out again at least once this week. Yea it does seem a little weird that the rpms are not there but I have no complaints on the performance. Patty will hover at just over 1/3 throttle and will pull out with authority! I'm not so sure that rpm is the only yardstick when measuring propeller performance. I mean I could wrap 20 inches of weed trimmer line around the crankshaft and it would turn up a about a gazillion rpm but the thrust would be zilch. Anyway , you get my point, the real world test is to go fly it and see how it works in the sequence. I haven't got around to the APC 20x10 yet, that is one I am going to try soon, my only concern is downline braking, there doesn't seem to be a lot of blade area out there. The Moki 20x10 and Mezjlik 20x10 are two other props I want to try, especially the Moki. Bring your Edge over some time, I haven't seen you fly that one yet.

jmw:)