Mastertech

My Feedback: (31)

Having flown some late model pattern models with 2 strokes and 4 strokes why would you chose one over the other? Without this thread turning into a pissing contest about which is better please explain why you fly one versus the other.

MHester

My Feedback: (1)

That's not possible. [8D]

-M

Adamg-RCU

I agree completely, Mike ;>

flyintexan

My Feedback: (1)

I disagree completely.

MHester

My Feedback: (1)

You know, this could very well be a sign of the apocalypse, but I may actually try a DZ 160 this season. Just in a back up plane, and then run the living crap out of it just to answer some questions I have about "why". After all, I can't really and truly condemn unless I have first hand knowledge can I? Although, some might tell me I don't have to stick my hand in a fire to see if it's hot......well, I do, I'm that way. I hate to admit it, but I haven't been fair. Oh I've teased a lot, but I admit it, I haven't personally given it a fair shake.

So I hereby promise to hold my tongue (or fingers in this case) until I have run one PERSONALLY and can really be objective from a first person perspective. Fair enough? Heck I may fall in love with the thing. But I believe I want to see for myself.

Plus Lamar Blair doesn't live that far away

-Mike

PS God help me.

Eric.Henderson

I love them both, the types of engines, not the previous post'ers

There is no "better" when you get into 2 vs 4 cycle, there is just preferences, These are based upon many parameters, some are common and some are not. With almost equal power from both types it boils down to personal taste.

my two penneth or 2-cents

Schpankme

Regarding 2 vs 4 cycle engine, are we talking Methanol or Petrol (gas) ?

If you intend to use Methanol, do you intend to use straight FAI Fuel (Zero Nitro) ?

If you decide to run the Methanol/Nitro combined fuel, what percent of Nitro will you be requiring (5, 10 , 20 , 30 %) ?

Will you be wanting to use a Fuel Pump or Regulator ?

Will you be wanting to use electronic ignition or glow plug or other ?

What type of Oil have you decided to use - Synthetic, Mineral, Castor, Blended, POA/PAG (Ester) ?

Have you investigated your options for the type of Header and Tuned Pipe to use ?

Have you decided on the type of Engine Mount, and will you be needing a Nose Ring ?

Do you fancy planes with Cowls or Cowl-less ?


Should we discuss Electric as an alternative fuel [sm=drowning.gif]

_________
Schpankme

"stand you and deliver or the devil he may take ya" - Wiskey in the Jar

MHester

My Feedback: (1)

I think my brain just exploded........

-M

Angus Balfour

I prefer four stroke to two stroke as you get more pull, can control the speed better and i think they sound more purposefull.

Haven't tried electric but they do seem good. Not as powerfull as a YS160 though.

Angus

Mastertech

My Feedback: (31)

Eric

This is why I'm torn between the two, I've been flying my friends Focus with a 1.40 OS and just love the way the engine pulls and the lack of vibration is whats got me to thinking about using this engine in a new Focus 2. I flew pattern when it wasn't turn around and made the transition to turn around for a few years and actually love what I thought I'd hate. I was forced to quit for about 10 years. I was flying 4 strokes in a Jekell when everyone else was flying 2 strokes, late 80's btw. I built a Prophecy with a 1.20AC YS and didn't fly it much. Loved the way it pulled but really hated the vibration even with a Hyde mount. Seems it was always shaking something loose. I've really noticed the lack of crisp throttle response from the 2 stroke when compared to the response of a 4 stroke. I intend to fly in Advance this coming year when I can make a contest and Looking at the sequence it appears to be a power hungry class. Given the cost of a 1.60DZ and the cost of a 1.40 OS and the cost of running the two I'm leaning towards the OS. Do you think the OS will be fine in this class with a Focus 2?

Chris Moon

My Feedback: (8)

I'm going to be flying the OS 140 in Advanced this year also. I flew 2 contests last fall in Advanced, and it pulls my 10 3/4 lb Eclipse fine. The 4 stroke does have more low end power, so it will accelerate better from low throttle, but that's just a function of the power curve on a 2 stroke vs 4 stroke. Some like one - some the other. I like a "simple" and reliable setup that won't need to be fussed with and won't make my Eclipse into a glider in the middle of a contest round. I believe that the YS DZ and the upcoming YS 160 have more power than the OS 140, but my goal is to have power AND reliability. When I go to a contest and see 4 of 10 Masters flyers (all 4stroke) deadstick in round 1 with various issues from broken internals to regulator and needle settings, I will vote for a little less power but relaibility every time. My motor has not quit in flight once since new (300 + flights) which is why I bought 2 more.

Angus Balfour

Thats highly unusual to have that many fliers have that many problems with YS. I would say from what ive seen they are equally reliable but fourstrokes are perhaps more reliable to start.

At the end of the day an OS 140/160, YS 140/160 or electric will all power the modern F3A model with ease, it's purely down to personal taste.

Angus

ps the only time my YS cuts is when i tell it its allowed to

Rhilluk

I think YS's need a little bit of TLC with operating, they like the right fuel and the right mixture. I'm having some probs getting my ys .63 to idle properly, but I think thats to do with the idle mixture.

But my ys has never quit either !

PepsiMike

twtaylor -

An OS140RX will do fine in a Focus. A couple of years ago Peter Collinson used this combination while flying FAI, so it definately has the power. For getting back into pattern I recommend using the OS - just fewer moving parts. The YS DZ engines are amazing things to behold, but are a little more involved in set up and love 30% nitro (which ain't cheap).

If you plan on using your Prophecy, you will have to do major surgery to the belly in order to accomidate the longer 2 stroke pipe. That might influence your decision. The YS 140 Sport will work well in the Prophecy and I'm sure you could reuse you old header and pipe combo. The Sport is cheaper than the DZ's and will have plenty of power for the "narrow body" models.

BTW our NSRCA district 2 VP is Robert Gainey. You can e-mail him at: [email protected] to get info on whats going on. I believe we have a judging seminar scheduled for this winter Jan/Feb.

Mike Radeke

Chris-B-chips

while the 4 strokes do have more power down here on our side of the equator everyones switching to 2 stroke because they have had enough fidling with their YS. i don't know about you guys but i had to pour hundreds of dollars at me 140L before it ever ran the same. everyone (well everyone besides a few die hard 4 stroke buffs) are switching to 2 stroke beacause they WILL get more flying done with a 2 stroke. and not to mention they eat less fuel and run less nitro. if want power be prepared to have to pay alot of money in thge long run. if you want power and reliability go 2 stroke.

now that may not apply for everyone maybe its just down here in Aus where 4 strokes don't want to run reliably.

impactiq

My Feedback: (57)

I take a stab at this. If you ask me.... it is more of a trend then anything else. Back in the day of old school pattern. 2 strokes with pipes were king (in my book they still are). As the rules changed so did the engines/planes. The winning guys were using 4 strokes do to there better power curve compaired to the 2 strokes of that period. Thus, The winning combo is what everyone has to have.

In the 2 stroke world of engines, until recent years, engine companies (Webra,OS,etc..) are now making 2 strokes more " Pattern friendly" by todays standards. If/when some of the top notch pattern fliers start winning with these new 2 stroke combo's..... I predict a swing again of 4 stroke to 2 stroke......

can773

My Feedback: (1)

From the ICARE website....



I predict a swing to electric.....

TOYMAKER

My Feedback: (6)

I predict..... neutron accelerators capable of warp 10 speeds.

Beam me up Scotty....


On a serious note. Its what ever works for YOU and what kind of support can you get LOCALLY.

Cant get a rod or piston ring for your engine..... your not flying.
Cant get a needle valve or rocker.... your not flying.
Cant get parts for two months cause somewhere
in China or Italy your parts are still on a boat ... your not flying.
Dont know how to set the valves or a pump... your not flying.
Blow a speed controller..... your not flying
Fry a battery.... your not flying
Takes two months for the warranty to return
your engine............................................ ..............YOUR NOT FLYING.

Pick your poison and take the appropriate antidote.

Hmmmm I am so.... optimistic.... must be all this cold,wet,windy weather.
I'll be better when I have the sticks back in my hand again and my OS 1.40 is purring along.

Wayne G.

tph1

My Feedback: (12)

Wayne is running the OS 1.40 on dilithium crystals!!! I know the secret now.

Lancair-RCU

Im putting together my first 2M pattern plane and chose to use an OS140RX.

I read lots on these forums about the various motor choices and admitadly the YS140DZ was looking very nice. Then I remember the hassles Ive had with my YS63S, it is still really being broken in though. It seems as though it reacts a lot more to ambient temperature and local air pressure than my OS50SX.
I watched at the local pattern comps and saw the hassels everyone had with the OS140RX and the YS140DZ and other YS motors. Nearly every time the OS failed to start or stopped in flight was due to user error. Theres one guy flying an OS140RX who Ive seen blow out the glow plug at least twice, thats right, blow it out of the engine, not wrecking the thread, so it cant have been in too tightly to start with, poor pre-flight procedure and or poor maintenance ? The YS crew however, seem to have by far the most trouble in flight. One guy had deadsticks early in his 1st and 3rd round, in a one day comp, that killed his score bigtime.
Based on my observations, the relative cost difference outright as well as number of spare parts possibly req'd for long term running cost as well as the fuel cost, I went for the OS140RX.
Some may say Im mad to be building a 2M now, when Im still a very average flyer in sportsman, but my wife and I are expecting our first little co-pilot early next year, so it was a case of spend the money now or never.

Eric.Henderson

Ref. "Eric, Do you think the OS will be fine in this class with a Focus 2?"

Sure will. Ran 'em in the Focus (1) and the Focus-2 and my last Temptation.

Ran best with;

- pressure tap in back top left bolt-hole, just like the EFI and FI. (It's a $6.00 part that replaces the backplate bolt.)

- feeding pressure to tank for a Cline regulator.

- OS "F" plug,

- 15/16 Powermaster,

- Karl Mueller header,

- ES OS 1.40 pipe, any and all of the three lengths available,

- No tuning required. Just fit to Mueller header and fly!

- !7 x 13 APC.

- Hyde "A" Mount.

Regards,

Eric.

bla bla

Eric, are you refering to the OS 1.40RX or the 1.60FX when you mention using a pressure tap and a Cline?
If the 1.40, what are you doing about by-passing the pump? I would love to have an option that could do away with that part, one that was easily and cheaply replaced at the feild in case of failour.

oisf3a

Hello bla bla ...

In my new plane I will be using the OS140RX but with a Perry pump instead of the original one.
My original pump is not working and the Perry is a cheap and well working replacement.
I removed the original pump from the backplate, filled it with some epoxy and glass and at the same time molded in a pressure tap (heat treated to increase the epoxy temperature stability (TG)) for the pump.

In addition to this the needle valve assy was cut from the backplate and mounted on the firewall.
Only a very small hole for the needle extension is then needed. I also plan to mount a servo to the needle to experiment with finetuning of the midrange (mix slaved from the throttle)

bla bla

Jolly good!
Great to see you're hard at work also!
This is interesting stuff, why didn't we talk about this the other evening?
There seems to be a lot of back plate/epoxy voodoo going on in Dal... is this the simplest way?

Eric.Henderson

I was listing the stuff for my FX 1.60's. They work great with the Cline regulator and a pressurised tank. This is the least invasive way to get an OS 1,60 FX to behave like a pattern engine. You are required to prime the engine with a "thumb" over the carb before the first start of the day.

The OS 140 RX normally works very well with its own pump. I like that pump so much that I actually fitted OS 140 pumps to four of my OS l.60 FX's. This takes a lot of work with a lathe and a milling machine. The benefit is that it is a piece of cake to swap motors between rounds etc. It also primes by just turniing over the motor.

Eric.