MOKI RADIAL Care and Maintenence
#276

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Dear Moki Lovers,
Well my 30" x 16" 3-B prop came in from Xoar yesterday for my Moki 250. So, I drilled that bad boy and brought the plane outside on the driveway.
All I can say is awesome!!! What an awesome running & sounding engine. It has unbelievable power too... I can't wait to take it out to the field...
Greg
Well my 30" x 16" 3-B prop came in from Xoar yesterday for my Moki 250. So, I drilled that bad boy and brought the plane outside on the driveway.
All I can say is awesome!!! What an awesome running & sounding engine. It has unbelievable power too... I can't wait to take it out to the field...
Greg
#279

Thread Starter

Hey Chicken,
I think I know the answer......$500+ compared to $150+???
Hey Greg,
It was so cool hearing your enthusiasm after the run-up. They are so fun to own/operate and listen to. You have an unbelievably nice combo there in the LA-7. Can't wait to see it at Monster Planes. I'm with you whenever you're ready to maiden the engine. Very cool.....can't wait......can't wait!
See ya guys,
Scott
I think I know the answer......$500+ compared to $150+???
Hey Greg,
It was so cool hearing your enthusiasm after the run-up. They are so fun to own/operate and listen to. You have an unbelievably nice combo there in the LA-7. Can't wait to see it at Monster Planes. I'm with you whenever you're ready to maiden the engine. Very cool.....can't wait......can't wait!
See ya guys,
Scott
#280

500.00? I DONT REMEMBER PAYING THAT MUCH. DID THE NEW OWNER JACK UP THE PRICES..? I REMEMBER PAYING AROUND 380.00 FOR A 3 BLADER FOR MY P-40
#281

Thread Starter

77chknhwk,
You got me there
. I was just guessing. I was also guessing the reason Greg didn't go the SoloProp route???
I love SoloProp products and plan to buy one someday soon. I would sure think that once you get all the adapters and 30" blades you're going to be somewhere in the $400 range.
I think sometimes it just is easier to grab a fixed prop you know works well with an engine. No muss, no fuss...ya know
???
SJP
You got me there

I love SoloProp products and plan to buy one someday soon. I would sure think that once you get all the adapters and 30" blades you're going to be somewhere in the $400 range.
I think sometimes it just is easier to grab a fixed prop you know works well with an engine. No muss, no fuss...ya know

SJP
#282

YES SIR I DO KNOW WHAT YOU MEAN. ONCE A PERSON GETS THE HUB, BLADES ARE NUTHIN. 25-30 BUCKS A PEICE
IT DONT MATTER THO, A PROP STRIKE WILL COST YA EITHER WAY..
IT DONT MATTER THO, A PROP STRIKE WILL COST YA EITHER WAY..

#284
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Hey chicken, why would you put a solo prop on when the engine will have a spinner, you will never see the hub. I like the solo hub for corsairs, hellcats, P-47 etc but unless it is a case of an unavaiable prop size i dont see a major benefit against a fixed prop when the mechanism is under a spinner, unless it is a case of minor tweaking
good luck
Paul
good luck
Paul
#285

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Looks great, Greg.
By the way, where did you pick up the exhaust extensions? Did you just hose-clamp them to the stubs, or was there more to it than that?
Thanks
Noah
By the way, where did you pick up the exhaust extensions? Did you just hose-clamp them to the stubs, or was there more to it than that?
Thanks
Noah
#286

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With all due respect, I am going to have to respectfully disagree with you on this one Paul. With a fine scale aircraft like Greg's La-7 why spare any expense on any detail. Which he has proved already every step of the way, especially with the moki 250 in front. So unless you are looking to save money or its your personal preference....there are plently of reasons to use a solo prop.
Adjust pitch to change maximum engine RPM.
Adjust pitch to attain various flight parameters.
Switch propeller blades if different diameter is required.
Eliminates the need to purchase numerous propellers when testing for optimum performance
The blades are more scale there is no doubt about it.
It is all preference and whatever works for Greg is fine by me. But, I do think it is a valid choice/suggestion even with a spinner.
On a side note: Engine looks great Greg. I can't wait to see it fly.
#287

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ORIGINAL: butlern
Looks great, Greg.
By the way, where did you pick up the exhaust extensions? Did you just hose-clamp them to the stubs, or was there more to it than that?
Thanks
Noah
Looks great, Greg.
By the way, where did you pick up the exhaust extensions? Did you just hose-clamp them to the stubs, or was there more to it than that?
Thanks
Noah
Here is the link to them.... http://bennettbuilt.com/page5.htm They work great!!! Scott, told me about them...
Greg
#288

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ORIGINAL: 77chickenhawk
IM CURIOUS AS TO WHY YOU DIDNT GO WITH A SOLO PROP
OR DID I MISS THAT PART?
IM CURIOUS AS TO WHY YOU DIDNT GO WITH A SOLO PROP
OR DID I MISS THAT PART?

First things first!!! I have to pay off the Moki..... LOL The Solo Prop will be in my future for the LA-7!!
Greg
#291

boy,,, aint that the cruel reality
dont it suck we have to pay the bills first.. i have 3 in my hangar being build. and i cant do squatt till i pay off prior purchases for these birds.. what a beautyfull plane you have
dont it suck we have to pay the bills first.. i have 3 in my hangar being build. and i cant do squatt till i pay off prior purchases for these birds.. what a beautyfull plane you have
#293
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Hello Guys,
The 102" span, Wild Hare SU-26/ MOKI 150 make its first flight Friday. 8 oz of lead in the tail cured the CG problem. Bottom line..........I'm not happy with the way it flew. The engine was excellent, take off roll was smooth as it transitioned into the air and climbed with authority. After initial trimming it flew a scale like flight with good climb, did a few rolls and stalled it straght ahead. The set up for a landing was normal all the way down final until 2 feet from touch down. The angle of attack was normal, airframe level with the runway, carrying normal speed when it dropped like a rock, landed heavily on the gear, came to a sudden stop, knocking the tips off the birch prop. The gear was slightly bent outward but no other damage. I have a lot of experience landing many different types of planes and considered this to be typical until it fell out of the sky. I don't think I have ever seen an RC plane drop that fast.
My feeling is that the plane is too heavy. The MOKI added 4 lbs to the nose which had to be compensated for by moving batteries and other parts into the tail, plus the lead to get the CG at the rear of the wing tube. So where do we go from here? Future landings will have to be more P-51 like, carrying more speed down final. I'm looking for options. 1. Remove the engine and put it on another plane. 2. Shorten the engine box and engine cowl, moving the engine back 5" to allow less weight in the tail, keeping the CG correct, and lightening the plane. 3. Learn to live with the extra weight in a plane that normally flies light with the DA 100. I really don't like the stress that the weight is putting on the airframe.
Anyone have suggestions?
Jim
The 102" span, Wild Hare SU-26/ MOKI 150 make its first flight Friday. 8 oz of lead in the tail cured the CG problem. Bottom line..........I'm not happy with the way it flew. The engine was excellent, take off roll was smooth as it transitioned into the air and climbed with authority. After initial trimming it flew a scale like flight with good climb, did a few rolls and stalled it straght ahead. The set up for a landing was normal all the way down final until 2 feet from touch down. The angle of attack was normal, airframe level with the runway, carrying normal speed when it dropped like a rock, landed heavily on the gear, came to a sudden stop, knocking the tips off the birch prop. The gear was slightly bent outward but no other damage. I have a lot of experience landing many different types of planes and considered this to be typical until it fell out of the sky. I don't think I have ever seen an RC plane drop that fast.
My feeling is that the plane is too heavy. The MOKI added 4 lbs to the nose which had to be compensated for by moving batteries and other parts into the tail, plus the lead to get the CG at the rear of the wing tube. So where do we go from here? Future landings will have to be more P-51 like, carrying more speed down final. I'm looking for options. 1. Remove the engine and put it on another plane. 2. Shorten the engine box and engine cowl, moving the engine back 5" to allow less weight in the tail, keeping the CG correct, and lightening the plane. 3. Learn to live with the extra weight in a plane that normally flies light with the DA 100. I really don't like the stress that the weight is putting on the airframe.
Anyone have suggestions?
Jim
#294

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Hi all, and thanks for a very useful thread.
This summer I bought a Moki 150 for my CARF Yak 55 2,6 m. I had a 3W 106 in it before, but finally I decided to go for this marvellous radial. I mounted it directly to the firewall, well knowing that I probably should have shortned the dome some 30 mm. But if I did, I would miss the opportunity to serve the engine without having to demount it from the firewall. If the plane had a "normal fullsize" cowling, I'd definitely cut the dome, and mount the firewall further backwards. So, I ended up adding 300 grams inside the stab tube, and overall got a 1 kg + heavier plane. During the first flights it seemed to lack some power during the hardest verticals (Imac Sportsman), but now, after a total of 16 flights, the engine starts increasing power just that tad needed to stretch the vertical manouvers well over the top. Also, I have not tested other props (I use an Engel 29x12). 5000 rpm on ground. I will test other brands to see if they perform better.
Now something that confuses me a little: When purchasing this engine as a Moki 150 from www.airworld-online.de , the instructions says that oil mix should be 50:1 (2%). Pilots here in Norway have used this blend successfully for 300 flights. When purchasing it as a RSC 150 in USA, instructions there says 32:1. What's right? I use a premixed fuel designed for chainsaws etc, containing a high grade synthetic 2-stroke oil. Engine sounds very fresh. One minute after flight the cylinder temperature varies between 87-92 centidegrees. This seems just fine, doesn't it?
Edit: I had not read the very good input from douglasa on page four in this thread. Really good to finally know that I'm doing right using 50:1. Also, I'll test the Engel 28x14. Nice to read words like "For aerobatic aircraft far and away the best prop is the German Engel 2 blade carbon 28x14, my 150 (in a comp-arf 2.6 Yak) with just over 9 hours flying turns this at 5,500rpm on the ground." - kinda takes away some guesswork
Many thanks.
This summer I bought a Moki 150 for my CARF Yak 55 2,6 m. I had a 3W 106 in it before, but finally I decided to go for this marvellous radial. I mounted it directly to the firewall, well knowing that I probably should have shortned the dome some 30 mm. But if I did, I would miss the opportunity to serve the engine without having to demount it from the firewall. If the plane had a "normal fullsize" cowling, I'd definitely cut the dome, and mount the firewall further backwards. So, I ended up adding 300 grams inside the stab tube, and overall got a 1 kg + heavier plane. During the first flights it seemed to lack some power during the hardest verticals (Imac Sportsman), but now, after a total of 16 flights, the engine starts increasing power just that tad needed to stretch the vertical manouvers well over the top. Also, I have not tested other props (I use an Engel 29x12). 5000 rpm on ground. I will test other brands to see if they perform better.
Now something that confuses me a little: When purchasing this engine as a Moki 150 from www.airworld-online.de , the instructions says that oil mix should be 50:1 (2%). Pilots here in Norway have used this blend successfully for 300 flights. When purchasing it as a RSC 150 in USA, instructions there says 32:1. What's right? I use a premixed fuel designed for chainsaws etc, containing a high grade synthetic 2-stroke oil. Engine sounds very fresh. One minute after flight the cylinder temperature varies between 87-92 centidegrees. This seems just fine, doesn't it?
Edit: I had not read the very good input from douglasa on page four in this thread. Really good to finally know that I'm doing right using 50:1. Also, I'll test the Engel 28x14. Nice to read words like "For aerobatic aircraft far and away the best prop is the German Engel 2 blade carbon 28x14, my 150 (in a comp-arf 2.6 Yak) with just over 9 hours flying turns this at 5,500rpm on the ground." - kinda takes away some guesswork

#295
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Hi guys,
here the result of an experiment, to install a 5-blade prop in the size 28x16 to a Moki 250. The Waco is only the test platform for it,
the motor with this prop will be installed in a 1/4 scale Sea Fury from Jerry Bates. A small video of the first test run is [link=http://www.youtube.com/watch?v=p5piKp94CCY]here[/link].
It turns about 4200 rpm's, I think, its possible, to increase the size to 30x16. The prop is made from Zinger props and he took 125 $ +shipping. You see, it mustn't always be a solo prop.
Additional a few pics,
Bernie
here the result of an experiment, to install a 5-blade prop in the size 28x16 to a Moki 250. The Waco is only the test platform for it,
the motor with this prop will be installed in a 1/4 scale Sea Fury from Jerry Bates. A small video of the first test run is [link=http://www.youtube.com/watch?v=p5piKp94CCY]here[/link].
It turns about 4200 rpm's, I think, its possible, to increase the size to 30x16. The prop is made from Zinger props and he took 125 $ +shipping. You see, it mustn't always be a solo prop.
Additional a few pics,
Bernie
#296

Thread Starter

Jim,
I don't remember what you said the plane weighed before the Moki but 4 lbs is a bit of weight. If it's less than ten percent it shouldn't present that big a problem unless the plane was close to begin with. Assuming that's not the case I'm guessing a part of the resulting difference in landing is caused by the reduced RPM of the prop at idle. I will attempt to explain it this way. I too noticed that when I went to the Moki engine that I could idle the engine so low that it seemed the prop acted like an air brake more quickly reducing the aircraft speed and in some cases would approach a landing stall speed faster than when I had a two stroke twin in there. The idle RPM of the two stroke twin (3W-106) was considerably more than that of the Moki allowing the prop to pull the plane along more than slow it down. I'm not sure I'm correct there but when I adjusted my throttle up a few RPM for landings they became more like I was used to with the 106 twin. Hope that helps you. Thanks for your posts. Good luck with that Moki!!!
Mavpro,
Thanks for chiming in. We'd love to hear from all the Moki owners out there. I believe the switch to 50:1 is the right move also. I have switched to 50:1 mixture and have been happy with the results so far. Engine seems to run cooler and smoother. I know the plugs seem cleaner and extended runs at low throttle settings don't seem to have any hesitation spooling back up when I throw the throttle forward. Let us know how you make out with the German Engel 2 blade carbon 28x14 prop???
BigBoy99,
Love the video. The prop is awesome. I can't wait to see the maiden. The 1/4 scale Sea Fury is the first plane I saw the Moki in and loved it. It will be so cool to see that plane fly on a five blade prop. Best of luck to you with that project. Please keep us up to date with your progress.
Thanks to you all,
Scott
I don't remember what you said the plane weighed before the Moki but 4 lbs is a bit of weight. If it's less than ten percent it shouldn't present that big a problem unless the plane was close to begin with. Assuming that's not the case I'm guessing a part of the resulting difference in landing is caused by the reduced RPM of the prop at idle. I will attempt to explain it this way. I too noticed that when I went to the Moki engine that I could idle the engine so low that it seemed the prop acted like an air brake more quickly reducing the aircraft speed and in some cases would approach a landing stall speed faster than when I had a two stroke twin in there. The idle RPM of the two stroke twin (3W-106) was considerably more than that of the Moki allowing the prop to pull the plane along more than slow it down. I'm not sure I'm correct there but when I adjusted my throttle up a few RPM for landings they became more like I was used to with the 106 twin. Hope that helps you. Thanks for your posts. Good luck with that Moki!!!
Mavpro,
Thanks for chiming in. We'd love to hear from all the Moki owners out there. I believe the switch to 50:1 is the right move also. I have switched to 50:1 mixture and have been happy with the results so far. Engine seems to run cooler and smoother. I know the plugs seem cleaner and extended runs at low throttle settings don't seem to have any hesitation spooling back up when I throw the throttle forward. Let us know how you make out with the German Engel 2 blade carbon 28x14 prop???
BigBoy99,
Love the video. The prop is awesome. I can't wait to see the maiden. The 1/4 scale Sea Fury is the first plane I saw the Moki in and loved it. It will be so cool to see that plane fly on a five blade prop. Best of luck to you with that project. Please keep us up to date with your progress.
Thanks to you all,
Scott
#297

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Who has had a valve stick??????? I did! Engine started running rough and we found a pushrod out because a vave had stuck in the open position. Ofcourse i thought it was bent but after cleaning the carbon off and oiling it, we re-installed the head and it ran fine. The last flight today i was getting some high speed missing but nothing too bad, hopefully it was just too rich and not the new cam sensor starting to go bad. I'll research it later this week. Jeff
#298

Thread Starter

Hey Jeff,
Glad to hear you caught the problem before...well you know. I have not had one stick but I've seen it happen a few times at Top Gun. Just this last year it happened a couple of times to the Italian crew flying a CompARF Corsair. Awful sounding when the rod falls out and it sticks in the open position.
The guys at RCS/TBM (Mike Dooley) showed me how to clean mine with carb/break cleaner to remove the carbon build up and then blow it out/off with a high pressure air hose. That seems to keep everything working on mine so far.
Anybody got better ideas regarding the cleaning of the valves please let us know. We all got lots to learn....
On that note, I had a question about the thread size of the tapped hole on the prop shaft of the 250 Moki. For anyone else that does not know already it's 4mm. at least on the 150, 215, and 250. TBM sells a handy adapter that takes it to 10-32 if you need to go that route. http://www.troybuiltmodels.com/cgi-b...S150-215-250SA
Tell us how you would do it???
Scott
Glad to hear you caught the problem before...well you know. I have not had one stick but I've seen it happen a few times at Top Gun. Just this last year it happened a couple of times to the Italian crew flying a CompARF Corsair. Awful sounding when the rod falls out and it sticks in the open position.
The guys at RCS/TBM (Mike Dooley) showed me how to clean mine with carb/break cleaner to remove the carbon build up and then blow it out/off with a high pressure air hose. That seems to keep everything working on mine so far.
Anybody got better ideas regarding the cleaning of the valves please let us know. We all got lots to learn....
On that note, I had a question about the thread size of the tapped hole on the prop shaft of the 250 Moki. For anyone else that does not know already it's 4mm. at least on the 150, 215, and 250. TBM sells a handy adapter that takes it to 10-32 if you need to go that route. http://www.troybuiltmodels.com/cgi-b...S150-215-250SA
Tell us how you would do it???
Scott
#299

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ORIGINAL: Scott Prossen
Mavpro,
Thanks for chiming in. We'd love to hear from all the Moki owners out there. I believe the switch to 50:1 is the right move also. I have switched to 50:1 mixture and have been happy with the results so far. Engine seems to run cooler and smoother. I know the plugs seem cleaner and extended runs at low throttle settings don't seem to have any hesitation spooling back up when I throw the throttle forward. Let us know how you make out with the German Engel 2 blade carbon 28x14 prop???
Thanks to you all,
Scott
Mavpro,
Thanks for chiming in. We'd love to hear from all the Moki owners out there. I believe the switch to 50:1 is the right move also. I have switched to 50:1 mixture and have been happy with the results so far. Engine seems to run cooler and smoother. I know the plugs seem cleaner and extended runs at low throttle settings don't seem to have any hesitation spooling back up when I throw the throttle forward. Let us know how you make out with the German Engel 2 blade carbon 28x14 prop???
Thanks to you all,
Scott
#300
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Hi guys,
I'm a bit astonished, what kind of small props you are using in USA with the Moki. This engine has so much torque,
try it, I have flown my Waco 1/3 scale with the 250 Moki with a 32x22 Biela Prop, that was too much, after starting the plane rolled very strong to the left side,
now I fly with a 32x20 on it., here in Europe nobody uses sizes under x18 pitch.
Regards
Bernie
I'm a bit astonished, what kind of small props you are using in USA with the Moki. This engine has so much torque,
try it, I have flown my Waco 1/3 scale with the 250 Moki with a 32x22 Biela Prop, that was too much, after starting the plane rolled very strong to the left side,
now I fly with a 32x20 on it., here in Europe nobody uses sizes under x18 pitch.
Regards
Bernie