2-stroke or 4-stroke - better for beginner pattern flying?

It looked to me after having visited Horizon Hobby's website last night that the Webras had just been overhauled a bit. I went there to look at the weight of the Webra Speed 50 GT, but it's no longer listed. It's been replaced by a much more expensive Speed .55 GT. The price was close enough to the .61 GT that I'd just buy that because the .61 is so much lighter than the O.S. .61 FX or TT Pro .61.

If I'm wrong and Webra Speed 50 GTs are still shipping, by all means please let me know!

I gotta admit I admire guys like you than can spit out all kinds of meaningful performance and operational info like you do. I too am now getting into electrics and I am impressed with the power you can get with such small components.. (and so far, no complaints from the folks near the school I fly at)

Thankfully weatehr here in SD is nice just about every day. A little too windy today for flying my new foamy, but there's always tomorrow.

Hi again Ed P. Seems that your thread has been hijacked - but in a good cause ;-) Now back to your original post; Would I be better off getting a .60 sized two-stroke for this plane, - No, but if you must have a 2C stay on your side of the pond an get an Irvine!. Is it worth the extra money to get an O.S. Max Surpass .70 II four-stroke? - No, but it would definitely be worth the extra loot to get a Saito 82a. IMHO, the combo would be perfect. Will the four-stroke be harder to fly straight because of the extra torque? - No. Now make a decision, Please .

The tuning sheet I had showed sanding the middle portion of the main needles and filing off the tip to get the right idle and midrange mixtures. It has been a LONG time since I was that paper! I actually talked to Duke about the Eagle because it gave me such fits!

The problem wasn't so much with fuel leaking (which it did) but with tuning changes every click as the needle wobbled back and forth. It would actually get two clicks per detent, one on one side and one on the other! The needle would rock back and forth for each click. I finally took one side of the detent off and let the needle rest against one side of the threads.

The carb innards needed to be rotated to adjust midrange. It was a PITA until it was right.

Well, that makes perfect sense, Ed. They snuck one by me.

Ed Cregger

You know how they got power from those 2C in Pattern? PIPE! I've got a tuned pipe for a TT.46 Pro and WOW! mk

I had a ST (Saturno) .51 and a .56 that would both swing a 12" prop well in the midrange. They also sucked up the fuel!

CR

Paul Mc> I have never seen a ST 51 that ran well at lower revs. They always seemed

I concur about the design being excelllent. The problem was in the carb quality control. I talked to Duke Fox at the 1991 Nats, when I was there as a volunteer AMA worker. I was flying his Quickee and .50 Schnuerle engines. Duke said he thought he had a pretty good product. I replied that he was right but that they'd be excellent if the QC was better on the carbs. Duke said that if they made only model engines he could improve the QC. The problem was that Fox Manufacturing did lots of industry jobs and they made model engines only when the necessary machines were available. There was more to it than thet, but that was the main thing.

CR

Peaky or not on a pipe depends on the pipe. Run a broad band pipe and the peakiness goes away. BTW, I have used a YS .45 in this way.

CR

Ed Cregger wrote:

Reading other posts on RCU I think you are both right. ST apparently has made many changes to this engine, including porting and other perfomance factors.

Well, to anybody who was actually following this thread, I decided to take Ed Forsythe's advice and poop or get off the pot. It seems that pattern flyers prefer 4-stroke motors these days, so I went into my favorite local hobby store with Platinum Visa in hand to see what they had to offer. My choices were:

O.S. Max FL-70 ($178) O.S. Max FS-70 Surpass II w/ pump ($289) Saito FA-72 ($217) Saito FA-82 GK ($268)

I went with the Saito FA-72. I was considering the FA-82, but I didn't want to pay $30 extra for a black and gold motor just so I could stick it under a cowling. Had the FA-82 been the plain silver model in the $239 ~ $249 price range, I would have stepped up.

I'm very confident that the FA-72 will be a great value for what I paid and it will provide terrific vertical performance for the Imagine 50. Wish me luck with it!

Ed Paasch

great value for what I paid and

I think you made a great choice and you'll be pleased w/ the performance. As for concerns about valve adjustment - just read the directions. It's *very* easy. I highly recommend getting a tachometer and breaking the engine in on a test stand. Sacrifice a gallon of fuel for a long, proper breakin and it'll last almost forever. After 15-30 minutes of run time, adjust your valves, as they'll probably be pretty loose by then. After that, check them again about 2 hours of runtime later, or sooner if you start detecting a loss of rpm/power.

I adjusted mine at those 2 intervals (Saito 91), once again after about

Enjoy and let us know how it works!

Tim

Ed,

I'm betting you're going to really love that Saito. I have some from .56 to

Good luck, desmobob

Hi Ed --

You will be quite pleased with the Saito. Funny how OS, YS, & Saito are always recommended and yet no one mentions Enya. I've had 'em all and they all are good, but I find the Enya to be the 'Maytag' of engines -- just keep running and running and running :-)

I have an article on "The Care and Feeding of Four-Strokes" at my Web Site; might I suggest you read it

Hi Ed, I'm sure you'll be happy with the 72. I would have gone with the 82 (same size, lighter, and more power) but the 72 will get the job done beautifully. I'm one of those "..ain't no such thing as too much power." troops - As long as you don't significantly increase the wing loading. .

I do not have any knowledge of current pattern trends, etc.

I would imagine that a .50 or .61 powered anything would not be competitive, even in Sportsman.

Ed Cregger

I don't know why not. A good .61 certainly has more power than a .70 or .81 four stroke. Presently the swing in pattern was back to 2 strokes. OS 1.4, 1.6, and Webra 1.6 are gaining in popularity, or at least they were a year ago.

Checked last yeas masters. The number of two strokes has almost caught up with four strokes. In fact they slightly outnumber the four strokes by 15/29 in the Masters class.