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OS 70 Surpass 4-stroke and 4 Star 40...?

Hi all,

I am looking for some opinions here: After an unfortunate series of events with my Cub (that started when the wheels left the ground this afternoon... ), I am left with an orphaned OS 70 Surpass II 4 stroke. Coincidentally, I have a Sig 4 Star 40 kit that I have been holding on to, and never built. What do the people familiar with the 4 Star 40 think of the combination of the 2?

I know the specs call for a .40 - .50 4 stroke, so this is on the large side... I am NOT an aggressive pilot, so this isn't to over-power the plane, just to make use of the engine and kit and get a new plane back in the air sooner. I was eventually going to buy a Saito .56 for the 4 Star, but haven't been able to yet (which is why I still have the kit laying around! :-)

So, what does everyone think, or even better, has anyone tried it (and the plane lived to tell about it?

My other option is to build another plane for the 70 4-stroke - I was considering the GP Ultimate Bipe (specs say 70 4-stroke will work). It is more aerobatic than I need, but it would be fun to build and fly a biplane (I think)...

Thanks!

John

Reply to
John Beck
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What do I think? Absurd. The Four Star 40 is overpowered by today's .52 Surpass!

My opinion is that you won't enjoy it with a 70 Surpass, especially if you're not an aggressive flyer. Buy an Astro Hog and put the 70 Surpass in that instead. Makes a good excuse to buy another kit and the Hog and a 70 Surpass make a wonderful combo. Terms of Reference: Flown Four Star 40 with Enya .53 four stroke and seen a gazillion of 'em fly with Saito, OS and Enya fitouts (my own has a Super Tigre S40K in it, the Enya CX45 was tested and considered overkill) and the Hog with a 70 Surpass. Hear all the usual crap about how "you don't have to use full throttle"....yer...right...uhuh!

Saito 56 is more grunt than you'll require in the Four Star 40.

Sounds the smarter move to me. Plenty of subjects to choose from. Hog et al.

p
Reply to
pimpf

I've just (as in two days ago) finished my 4 Star 40 and use a 52 four stroke. I had to move the battery and rx back a fair way to balance the model, so I think they'd be near the tail with a .70 up front. It's been too windy to fly here, not to mention to small problem of having to work until dark, but based on previous experience with similar size models, I don't anticipate any shortage of power with my 52 powered version.

Reply to
David Smith

I flew my 4 * 40 for about 3 years with a Saito .65. I liked the combination plenty of torque but not overpowered. I had to use 3 1/4" wheels to get prop clearance for the 13" prop.

Awhile back I switch to a Saito .56 to be honest the plane flies better now. It was always nose heavy with the .65

The .70 should work ok.

Reply to
emcook

A friend in our local club tried to run his 4*40 with an OS 70 and wasn't happy with the result. He felt that he didn't have sufficient rudder area to always deal with the torque it created. In the end he went back to a 46 2 stroke and finally a 52 4 stroke and is much happier.

Chris

John Beck wrote:

Reply to
Chris Spierings

Reply to
jflongworth

I've been flying my 4 star 40 with an ASP .52 four stroke and the power suits the model well. It isn't going to climb vertically very far, but there is enough to get most standard aerobatics out of it, and there is a lot of pleasure to be had from nursing a model through the manoeuvres rather than point and squirt flying.

Reply to
David Smith

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