FlyingPilgrim

My Feedback: (26)

I happened upon a NIB Dazzler kit recently, and when I read up on the threads for Dazzler and Uproars, it does not appear anyone uses a four-stroke in theirs- Why? I have a Magnum .46 and a .52 FS, both weigh the same (the .46 is a little heavier by about an ounce or two), similar performance (.46 2-stroke will probably have an edge in umph). With the plane limited on fuel tank capacity, it seems more would use a four-stroke for better "milage" of less fuel used. Just wondering if anyone has a four-stroke in theirs, or if there is a solid reason everyone is using a 2-stroke in this plane.

ChuckW

I imagine it is just economy or simplicity. A lot of the 3D guys use 4-strokes in their profiles so I see no reason not to put one on a fun flyer like a Dazzler or Uproar.

Gray Beard

My Feedback: (-1)

The reason was the Dazzler and Roar were fun fly planes. Not a lot of guys used them for sport planes. Fun fly events are a strange thing, you are doing a lot of things with them that gave them a short life span and some very serious crashes, or very hard landings if you like. They were designed to die so you didn't want to be installing any high end gear or engines in them. I used nothing but cheap standard servos and the OS .46 LA engines in any of mine. The Dazzler was the pretty boy of fun fly with the turtle deck and swept control surfaces. Both the Roar and dazzler were kits only for years and both kits were designed to be quick and easy builds. If I started building a Roar this morning at 8 I could be competing with it tomorrow at 8. The longest part of the build was waiting for the epoxy to set up. If you had a high dollar engine in your plane and one of the stunts was the target spot landing and you were going to over shoot your target I somehow feel you would give the full down elevator splat a second thought. If it came to be a win or loose part of the contest my plane would loose so I could win. No mater, I usually had several of the Roars in my pit for the next round if the contest director didn't have a one plane rule. A four stroke engine cost a bunch more then my complete plane, more like two planes. That's the why of it.

ho2zoo

My Feedback: (5)

I have an ARF Dazzler with a Magnum .52 four-stroke. It flies great! However, sometimes I wish it had just a little more power. It doesn't quite have the oomph to do true 3-D manuevers. (Not that I have the ability!) The engine is several years old, so maybe it's just getting a little weak, but it still runs well. I get ten minute plus flight times with the stock tank.

FlyingPilgrim

My Feedback: (26)

Well, I just discovered one reason to favor the 2-stroke. When mocking up the engines in the engine mounts, the 4-stroke must mount about 3/4" forward of the position of the 2-stroke. This moves the C of G forward for a plane that is already very nose heavy. I'll look at some other mounts to see if I can get it closer to the firewall.

Gray Beard

My Feedback: (-1)

That carb does get in the way sometimes don't it!! In a kit built plane you can move the fire wall forward and back until you find the magic spot. Not so much with the new ARFs.

FlyingPilgrim

My Feedback: (26)

Yeah, usually you can modify the firewall without much of a problem, but the design of this kit is such that there is no room for the fuel tank (if you want much flight time). After I thought about it more, I don't think the C of G will really be shifted that much by the engine sticking out 3/4" more. I'm digging through my boxes of parts to see if I can find some independent T-shaped beam mounts that will allow me to move it back some. Thanks for your input guys.

Gray Beard

My Feedback: (-1)

I had a real problem with an OS 1.20 pumper when I was mounting this engine in a plane that I had run a YS 1.20 in. I didn't want to chop up or move the cowl just because of an engine swap. The cure was to just buy an OS aluminum motor mount. They are designed to allow the engine to go more aft without hitting the carb. 3/4 inch they won't cure though. 3/4 inch is a lot. Is this a kit or the ARF??

FlyingPilgrim

My Feedback: (26)

No, this is the kit. I think I may just use the .46 2-stroke and save the .52 for another plane. Like Ho2zoo said, I might want the extra umph. I'll fire up the 2-stroke on the engine stand and see if I can stand the sound of the high revving 2-stroke. If it grates on me too much [:@] , I'll go with the 4-stroke and just swallow the fact that it will need a little more tail weight.

FlyingPilgrim

My Feedback: (26)

Well, just an update- I used the 2-stroke, and it flies fine. I modified the firewall to allow use of an 8 oz flex tank. The Magnum .46 is plenty of power- it will take it straigh up out of sight! I moved the elevator servo into the back of the fuse and still had to add 3.5 oz of lead to get a balance of 3 7/8" (much further back than plans), which worked out fine. Won't hold knife edge yet, but still dialing in... Throws had to be increased from plans as well. I'll post pics soon. Thanks for interest!

Gray Beard

My Feedback: (-1)

Glad for the update. When I was building them and flying the fun fly events I used the OS .46 LA. Even with the small fuel tank I could fill up once and fly the complete event on one tank. Fuel was never a problem but the tank was a tight fit.