Which 25 two stroke??
08-17-2007, 09:39 AM
#27
Senior Member
RE: Which 25 two stroke??
The 3243 tuned muffler for the .21-.28 engine weighs approx 3oz.
I don't know if anyone truly knows the deal with Morris Hobbies. They dealt with several good euro-brands (Moki/Mark, Rossi, MVVS), and seem to have gotten out of it altogether. They did in fact have their Rossi distribution rights up for sale a while back because it was posted on the Morris website as such.
I'm not completely surprised by this given the poor Euro to Dollar exchange. It would be tough to make any money selling motors in a market saturated with cheap clones. Note the low US profile of most european engines. They're out there, but not in any real numbers. It's the money!
Pe' and Dar are your best resources for the MVVS brand. I've not dealt with or communicated in any way with David Moen in Canada, so I can't comment one way or another in regards to him.
Pe's shipping cost are high, but he doesn't set the postal rates out of NL. Dar's shipping is surpringly low (and fast) out of Israel.
Either guy will give you first class service. Some of the best to be had anywhere.
08-17-2007, 02:27 PM
#29
Senior Member
RE: Which 25 two stroke??
"designed" to run straight castor? Exactly what kind of design would that be?
Here's the "official" recommendation taken from the MVVS website "Questions and Answers" section...
************************************************** **************************************************
OTAZKY A ODPOVEDI
1. Jake palivo pouzivat pro zhavici motory MVVS ?
Doporucujeme pouzivat kvalitni palivo s ricinovym olejem v pomeru 1:4 (20% oleje). Tento pomer je vhodny i pro zabeh. Nepouzivejte nevyzkousene synteticke oleje!
************************************************** ************************************************** *
So there you have it. Plain english.
They're recommending castor at 20% oil volume, and in so many words saying to avoid use of straight synthetics. I'd imagine that in some parts of the world where these things are sold, TRUE 80/20 FAI fuel is an easy thing to get. It's sure easy to make.
There's really good synthetics, and there's really bad synthetics, and they have no idea of which you plan to use. Castor is a safe recommendation. Not carved in stone (and Pe' would verify this), but it keeps MVVS out of the doghouse.
No manufacture of ABC/AXX engines recommends the use of straight synth anyway. The engines like the pinch protection of castor.
Here's the "official" recommendation taken from the MVVS website "Questions and Answers" section...
************************************************** **************************************************
OTAZKY A ODPOVEDI
1. Jake palivo pouzivat pro zhavici motory MVVS ?
Doporucujeme pouzivat kvalitni palivo s ricinovym olejem v pomeru 1:4 (20% oleje). Tento pomer je vhodny i pro zabeh. Nepouzivejte nevyzkousene synteticke oleje!
************************************************** ************************************************** *
So there you have it. Plain english.
They're recommending castor at 20% oil volume, and in so many words saying to avoid use of straight synthetics. I'd imagine that in some parts of the world where these things are sold, TRUE 80/20 FAI fuel is an easy thing to get. It's sure easy to make.
There's really good synthetics, and there's really bad synthetics, and they have no idea of which you plan to use. Castor is a safe recommendation. Not carved in stone (and Pe' would verify this), but it keeps MVVS out of the doghouse.
No manufacture of ABC/AXX engines recommends the use of straight synth anyway. The engines like the pinch protection of castor.
08-17-2007, 02:48 PM
#30
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RE: Which 25 two stroke??
The rear mini pipe set up will be less than 3 oz. All the ones I have bought have been set up with fairly high compression ratios so do not like much nitro and I run mine on 20% castor 75% METHANOL 5% NITRO. But they come with head shims and you can lower the compression ratio and run more nitro.
The supplied plug is good for running in but play around with others and you may see a RPM increase. Enya 3 works most of the time on 5% but you must fit a colder plug if running more nitro even with the head shimmed. Ground RPM figures are meaningless as it gets on the pipe in the air.
Here is a pic of my set up in a combat model.
The supplied plug is good for running in but play around with others and you may see a RPM increase. Enya 3 works most of the time on 5% but you must fit a colder plug if running more nitro even with the head shimmed. Ground RPM figures are meaningless as it gets on the pipe in the air.
Here is a pic of my set up in a combat model.
08-17-2007, 03:19 PM
#31
Senior Member
RE: Which 25 two stroke??
...but thinking about the OP's plans for this as yet undisclosed engine....
In a weight critical model such as the Shrike, it's going to be tough to go to a significantly larger displacement engine and not pay a dear price in terms of weight. Adding weight is never going to be productive.
It may be wise to stay with a similar displacement, and instead go for a performance oriented engine. in that size range. Sure MVVS makes a cool little .15, but I don't know much about it beyond that.
A readily available alternative would be the OS .15CV-A. Those little things HONK, and they're in line weight-wise with other .15's.
They're not giving them away either, but....you pay for your thrills.
Something to consider anyway.
In a weight critical model such as the Shrike, it's going to be tough to go to a significantly larger displacement engine and not pay a dear price in terms of weight. Adding weight is never going to be productive.
It may be wise to stay with a similar displacement, and instead go for a performance oriented engine. in that size range. Sure MVVS makes a cool little .15, but I don't know much about it beyond that.
A readily available alternative would be the OS .15CV-A. Those little things HONK, and they're in line weight-wise with other .15's.
They're not giving them away either, but....you pay for your thrills.
Something to consider anyway.
08-18-2007, 05:52 AM
#32
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RE: Which 25 two stroke??
You just answered your own question about weight. Get the Thunder Tiger GP 25 bushed engine and not break the bank on a high performance 15..............
http://www.acehobby.com/ace/TTR9020.htm
With practical RPM up to 17,000 and true SCH porting unlike the OS LA line this would be a win-win.
http://www.acehobby.com/ace/TTR9020.htm
With practical RPM up to 17,000 and true SCH porting unlike the OS LA line this would be a win-win.
08-18-2007, 07:24 AM
#33
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RE: Which 25 two stroke??
ORIGINAL: RaceCity
"designed" to run straight castor? Exactly what kind of design would that be?
Here's the "official" recommendation taken from the MVVS website "Questions and Answers" section...
************************************************** **************************************************
OTAZKY A ODPOVEDI
1. Jake palivo pouzivat pro zhavici motory MVVS ?
Doporucujeme pouzivat kvalitni palivo s ricinovym olejem v pomeru 1:4 (20% oleje). Tento pomer je vhodny i pro zabeh. Nepouzivejte nevyzkousene synteticke oleje!
************************************************** ************************************************** *
So there you have it. Plain english.
They're recommending castor at 20% oil volume, and in so many words saying to avoid use of straight synthetics. I'd imagine that in some parts of the world where these things are sold, TRUE 80/20 FAI fuel is an easy thing to get. It's sure easy to make.
There's really good synthetics, and there's really bad synthetics, and they have no idea of which you plan to use. Castor is a safe recommendation. Not carved in stone (and Pe' would verify this), but it keeps MVVS out of the doghouse.
No manufacture of ABC/AXX engines recommends the use of straight synth anyway. The engines like the pinch protection of castor.
"designed" to run straight castor? Exactly what kind of design would that be?
Here's the "official" recommendation taken from the MVVS website "Questions and Answers" section...
************************************************** **************************************************
OTAZKY A ODPOVEDI
1. Jake palivo pouzivat pro zhavici motory MVVS ?
Doporucujeme pouzivat kvalitni palivo s ricinovym olejem v pomeru 1:4 (20% oleje). Tento pomer je vhodny i pro zabeh. Nepouzivejte nevyzkousene synteticke oleje!
************************************************** ************************************************** *
So there you have it. Plain english.
They're recommending castor at 20% oil volume, and in so many words saying to avoid use of straight synthetics. I'd imagine that in some parts of the world where these things are sold, TRUE 80/20 FAI fuel is an easy thing to get. It's sure easy to make.
There's really good synthetics, and there's really bad synthetics, and they have no idea of which you plan to use. Castor is a safe recommendation. Not carved in stone (and Pe' would verify this), but it keeps MVVS out of the doghouse.
No manufacture of ABC/AXX engines recommends the use of straight synth anyway. The engines like the pinch protection of castor.
-------------
Oh, excuuuuuuuuuuz me! I should have said "fit", not designed.
How long have you been making your own engines from scratch anyway? After all, pozers are the only ones that grind on someone elses efforts and then pretend they are real engine men.
Ed Cregger
08-18-2007, 09:03 AM
#34
Senior Member
RE: Which 25 two stroke??
Ed,
Are you for real? Pozer?
And exactly where is the "posing" taking place?
I run these motors. I don't leave them in boxes, I actually run them, so I have SOME basic inkling of an idea of how to do it, and do not require comittees, polls, and public affirmation of which way to turn the needle valve.
How many "Cregger .46's" are you running?
Unreal Ed. Add something to the discussion, or say nothing.
That irritates me man.
Are you for real? Pozer?
And exactly where is the "posing" taking place?
I run these motors. I don't leave them in boxes, I actually run them, so I have SOME basic inkling of an idea of how to do it, and do not require comittees, polls, and public affirmation of which way to turn the needle valve.
How many "Cregger .46's" are you running?
Unreal Ed. Add something to the discussion, or say nothing.
That irritates me man.
08-18-2007, 12:08 PM
#35
RE: Which 25 two stroke??
Mike, getting back to your original question about going faster on a Shrike 10, if you check out the Extreme Speed Prop Planes Forum here on RCU, you'll find people running OS .32SXs with tuned pipes on them.
The TT .25GP is a dog. My flying buddy has one and it is lame. The Pro isn't much better, from what I have seen.
I have 2 Mag .28s and can't keep them running without messing with them all the time. On my twin, I finally went to OS .25FXs
For readily available engines, the OS .25FX would be my choice. MVVS might be a great engine, but you have to get them, and parts, from Israel or Norway. That's not like your local hobby shop or overnight from Tower, Horizon or Hobby People.
If you don't want to mess with a tuned pipe, the OS .25FXs or .32SXs respond nicely to a Jett Stream tuned muffler. I have 2 on my .25FXs and they scream.
The TT .25GP is a dog. My flying buddy has one and it is lame. The Pro isn't much better, from what I have seen.
I have 2 Mag .28s and can't keep them running without messing with them all the time. On my twin, I finally went to OS .25FXs
For readily available engines, the OS .25FX would be my choice. MVVS might be a great engine, but you have to get them, and parts, from Israel or Norway. That's not like your local hobby shop or overnight from Tower, Horizon or Hobby People.
If you don't want to mess with a tuned pipe, the OS .25FXs or .32SXs respond nicely to a Jett Stream tuned muffler. I have 2 on my .25FXs and they scream.
08-18-2007, 04:39 PM
#36
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RE: Which 25 two stroke??
Search is over! Picked up a NIB FX25 for a good deal at our fly in today. I am still intrigued by the MVVS, wish it had support over here.
Thanks all, MikeB
Thanks all, MikeB
08-19-2007, 12:00 AM
#37
Senior Member
RE: Which 25 two stroke??
Good choice. You'll like that.
Someday you can have one of these.
(Just print out the picture, and put it in your wallet so you don't forget)
Someday you can have one of these.
(Just print out the picture, and put it in your wallet so you don't forget)
08-19-2007, 06:49 AM
#38
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RE: Which 25 two stroke??
Granted Ed The GP 25 is a dog compared to other 25's but this was a compromise between weight and more speed than a .15 . But then why stop at a 32 ? Might as well go to a 40 Nelson or 40 Jett.............Do I hear a K&B 61 Twister..........
OH well the choice has been made. The only downfall I see is the average OS25SX is reported to have a 6 hour run time before problems. I have two of them and they seem to need constant tuning on a Midwest twin stick I don't fly that often............
OH well the choice has been made. The only downfall I see is the average OS25SX is reported to have a 6 hour run time before problems. I have two of them and they seem to need constant tuning on a Midwest twin stick I don't fly that often............
08-19-2007, 10:11 AM
#39
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RE: Which 25 two stroke??
I looked at the GP25 and liked how light it was. I originally was going to install the GP28, but after waiting 2 months I cancelled my order and got my money back.
I have a TT07 and it is a dog! Easy to run and reliable, just no power.
I also have the TT46PRO. I know many love this engine and I have seen it scream, but I was never that impresed with mine. But I may have broke it in too rich and caused my own problems. Therefore I decided against the TT.
My OS32F is in a Kobra. Easy to tune, super reliable, great performance. So the 25FX was a good deal at the right time.
Any tips on break in? My Magum 15 is a screamer after the following break in.
Bump caster in fuel by 4%.
Preheat the cylinder to allow the piston to travel without scrubbing in the pinch zone.
Start her up with a small prop 9x4?
Peak it out and richen a click or two.
Let run 1minute, cool and repeat.
3x1 minute
3x2 minute
3x3 minute
Fly it
The Mag 15 has about 10 hours without a problem other than shutting down. I'll see how the OS holds up. I have heard so many good things about this engine.
Thanks again all
I have a TT07 and it is a dog! Easy to run and reliable, just no power.
I also have the TT46PRO. I know many love this engine and I have seen it scream, but I was never that impresed with mine. But I may have broke it in too rich and caused my own problems. Therefore I decided against the TT.
My OS32F is in a Kobra. Easy to tune, super reliable, great performance. So the 25FX was a good deal at the right time.
Any tips on break in? My Magum 15 is a screamer after the following break in.
Bump caster in fuel by 4%.
Preheat the cylinder to allow the piston to travel without scrubbing in the pinch zone.
Start her up with a small prop 9x4?
Peak it out and richen a click or two.
Let run 1minute, cool and repeat.
3x1 minute
3x2 minute
3x3 minute
Fly it
The Mag 15 has about 10 hours without a problem other than shutting down. I'll see how the OS holds up. I have heard so many good things about this engine.
Thanks again all
08-20-2007, 05:36 AM
#41
Senior Member
RE: Which 25 two stroke??
ORIGINAL: speedster 1919
This should be a good project to put on a MAS 8x6 3 blade prop for speed............
This should be a good project to put on a MAS 8x6 3 blade prop for speed............
For speed, an 8x6 two-blade prop would be spun much faster, resulting in even more speed...
08-20-2007, 05:55 AM
#42
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RE: Which 25 two stroke??
Yes Dar --A 2 blade will swing nore RPM's in an 8x6 but I'm sticking my neck out predicting the 3 blade will unload nicely in the air on a small Shrike. An 8x7 two blade would be a good choice. In 9" you have to get to a 3D type pitch for a 25 and he doesn't want power but speed.
