acerc

Oh come on, I know you have scrap lumber lying around, two minutes top to have it drilled, mounted, and measured. Anything beyond that and I'd have to say your not a real builder!!
ROTFLMAO!!!

p3arljam

My Feedback: (5)

Any reason this mount http://www3.towerhobbies.com/cgi-bin...ATG7&P=ML#tech wont work with Saito 100?

bigbird3

I give up jam. You can talk this thing to death or get on the stick! Just do it! Yes that mount will work. If it fits the engine, it will fit the plane. Just in case you aren't sure, call Great Planes and ask them. You haven't listened to us thus far! It's one thing to be analytical but at some point it becomes ANAL-ytical! Just get started on the dumb thing! It'll work fine. If you screw up something, no one will notice unless you tell them! Half the mistakes they won't see and the other half they won't mention.
bird

p3arljam

My Feedback: (5)

Actually I have listened to all the advice and i have not started on the engine install because I have been traveling for work. I came across that mount and thought it might be better to use that than to glue spacers to the firewall in case I decide to change the engine.

FlyerInOKC

My Feedback: (6)

It's in Campaign Illinois and he's not? Other than that I don't see why not.



https://www.youtube.com/watch?v=d31R9-G4OyM

acdii

Like I said, thats all the time it would take for me to make the measurements.

Cub Man

My Feedback: (50)

Just wanted to say thank to all. Now thru Dec 30[SUP]th[/SUP] take 20% off all LED’s and 10% off all plans Feel free to order even if items are shown out of stock. I have new stock in and did not get the numbers changed before the holidays. Again Thanks for your support.
Use code Thanks for 20% off Led’s
Use code thanksplans for 10% off plans
www.thecubden.org/store

52larry52

My Feedback: (1)

I need some input from my fellow Cub Brothers (and sisters if there are any) on powering my latest Cub acquisition. I have a lot of assorted size glo powered Cubs, from 58" two stroke .25 engine to 100" 1.20 four stroke engine and six other in between size glo Cubs, some four stroke some two stroke. I thought I had a pretty good idea of how to power any size Cub but I'am not sure on this one.......it's a new Phoenix Super Cub ARF. The specs are 90.5" wing span (my tape measure says 91"), 11-12 lbs RTF, 57.9" long, full wing not clipped, wing area 78.7 dm2, and Phoenix calls for a 1.20 two stroke or a 1.50 four stroke! To me that sounds like way more engine than any Cub this size and weight would need for safe normal scale flying. I do fly off grass so I don't want a marginal power set up that struggles to get thru the grass on takeoff but a 1.50 four stroke??? Come on, that set up wouldn't need any runway for take off, just stand it on it's tail, rev her up and go vertical! Not Cub like at all. This airframe is very close in size and weight to a G.P. 60 size kit built J-3 Cub and G.P. calls for a 60-90 two stroke or a 70-90- four stroke. My gut feeling is a 90 four stroke would fly this Phoenix Super Cub quite well. In my "in stock" engine inventory I have the following choices...two stroke OS 61 FX, or Super Tiger 91, four stroke OS 91 Surpass, or older OS 1.20 non surpass. Which engine would you pick, or none of the above and do you agree that Phoenix has overstated the engine requirements for this plane? Thoughts and comments welcomed.

hairy46

My Feedback: (1)

It would depend on what altitude you fly, I fly at all most 7thousand so I do tend to over power here, the 150 would be my first look, but the 120 if I had one would be a choice, here I would not go under the 120, the little 40 planes always get a 55 because the 40s here just is not enough. I would mention the altitude you plan to fly from and those guys can give you a better choice, I would rather have a bit more and back off, then not have the power when needed.

52larry52

My Feedback: (1)

hairy46, Thanks for your input. The fields I fly at range between 500 and 1,000 feet above sea level so altitude is not an factor for me. I have all of the engines I mentioned but I have not run the older OS 1.20 yet. It lacked an exhaust system when I acquired it, I have since found and purchased one, and would test run the engine on a test stand before committing to installing that engine. The OS 91 Surpass is new and has been test run (Nice runner of course!). I actually have a Saito 1.50 in my engine stash but I have another larger plane in mind for that engine (a 98" Cessna Bird Dog) and feel it would be "wasted" on this Cub. If feasible, I would prefer to use something I have and not have to buy yet another engine. Maybe I should get that 1.20 on the test stand this week and see how it runs (and IF it runs). Thanks for your thoughts.

John_M_

Hey Larry, we have a guy at our field with a Saito 1.80 in a H9 1/4 scale Tiger Moth... its got more than enough power for scale flying, but it sure does sound nice with the "throttle" cut back to 33%... half throttle is the most he really needs, but the extra power is some nice insurance... he let me fly it around a bit and its very manageable, and doesn't feel that over powered... I would go with the 1.20 for sure... you can always play with your prop selections as well.


John M,

FlyerInOKC

My Feedback: (6)

I lean toward the OS 91 Surpass four stroke I think it would do everything you want and more.

acdii

Personally a Saito FA-100 would be perfect for it, but since you have a 91, I would try that one first. Check the case of the 91 and 1.20 and see how much there is a difference in size to see if you could install the 1.20 if the 91 isn't enough without having to make a bunch of mods. Maybe use a GP motor mount that can be adjusted.

rafeeki

My Feedback: (11)

If your OS 120 is a 4 stroke I would go with it.
Rafeek

p3arljam

My Feedback: (5)

Can anyone tell me on the Great Planes 60 Cub why the firewall is recessed in the fuselage ? With my Saito 100 mounted all the way forward on my mount i am still going to have to add about 1 1/4" of plywood spacer behind the mount in order to get the drive washer to the proper length?Are all Cub firewalls like this?

acdii

Nope, just the Great Planes. My friend has the GP ARF, his is recessed as well, so I know what you are talking about. I don't know what mount you are using, but he has a SIG mount for his OS 70 and it fits perfectly.

FlyerInOKC

My Feedback: (6)

It's called a box style firewall. I actually built that type of firewall for my SIG 1/5 Cub to allow a Saito .80 to fit without extending the nose and ruining the profile. With the engine I chose the carburetor is on the back side of the engine and wouldn't fit in the area provided. This is a common firewall design when you have a short nosed airplane like a WWI Fokker when you want to make it as scale as possible.

You may want to find a two piece engine mount (like a SIGEM003) or and adjustable firewall (Great Planes GPMG1091) with longer beams for mounting the engine.

I_Fly

The recessed firewall is common on cubs this size. I'm not sure why but it could be a way of simplifying or reducing the size of the cowl while still allowing room for the engine. It sounds like your engine mounts may be too short. They come in different sizes. Possibly you need the next size up? The FA100 is not a small engine so I'm surprised to here that you have this issue. Many have mounted smaller engines into these planes and they are designed for a .60 two stroke. Probably smaller than the Saito you are trying to use.

Good luck with whatever solution you choose.

SrTelemaster150

The FA-115 is smaller than the FA-100 in physical size & footprint.

SrTelemaster150

The FA-115 has the same footprint as the FA-80

Mark@ny

My fathers 1/4scale clipped wing cub flew well with an OS 1.60 Gemini twin. But for something your size I would think the 1.20 would be plenty the 90 4stroke probably even more scalelike. I would rather have the extra ponies and keep it throttled back. I guess they recommend even bigger for sailplane towing and for guys doing 3-d. (I have no idea why) or maybe it really needs the power on to keep it in the air instead of floating along. We have all had a flying brick at sometime.
The following is from sig for their 1/5 cub
Clipped Wing Cub
Wingspan 84.5 in 2146 mm 68.3 in 1735 mm
Wing Area 947 sq in 61.1 dmē 752 inē 48.5 dmē
Fuselage Length 55.3 in 1403 mm 55.3 in 1403 mm
Flying Weight 7 lb 3200 g 7 lb 3200 g
Radio Required 4-Channel with 5 Servos (not included)
Engine Required
(not included) 2-Stroke .40 - .45 (6.5 - 7.5 cc)
4-Stroke .45 - .60 (7.5 - 10.7 cc)

Good luck

Mark@ny

Is the Phoenix 1/5scale cub all up weight is close to 13-15lbs like it says? The 1/5 sig is more like 7-8 that could be why they recommend the bigger engine.

52larry52

My Feedback: (1)

Thanks to all who responded to my request for help in selecting an engine for my Phoenix Super Cub. Yes, the OS 1.20 is a four stroke. It is an older design from the late 80's to early 90's and is physically a much larger engine than the newer OS .91 surpass and would not be a direct interchange. The crankcase width and nose length are quite different. The OS 1.20 size would be a direct interchange with the Saito 1.50 but the Saito is not going into this Cub as I bought it for the Bird Dog, so it's out of the mix except for size reference. I do have a coupe of large GP adjustable engine mounts so drilling one for the OS .91 and the other for the OS 1.20 is doable. I would leave the cowl off and uncut if I were to try both of the OS four strokes so no problem there. I was unable to work in the shop today but I did go down there a short time ago to follow up on some of the ideas and questions presented in your responses and found that the OS 1.20 now seems to have no compression. I know it did when I put it away 3+ years ago but not now ! Tomorrow I will spend the day in the shop, disassemble the 1.20 as needed to find the problem, run it if I can, and narrow down the engine choice field. The 1.20 may turn out to be a "boat anchor" (model boat of course ). I let you know what I find. I'am hoping it is just "crap" on a valve head and not sealing but I'am not always that lucky .

SrTelemaster150

No it won't work, it has already been tried, it is too wide. You need the 60-120 SIZE. FA-120/150/180 are big blocks. The F-A-100/125 are oddball sizes & fit the smaller medium block size mount.

http://www3.towerhobbies.com/cgi-bin...&I=LXJ773&P=ML

Cub Man

My Feedback: (50)

I know the goldburg cub fire wall also sets back in a little. To me this makes a much stronger setup.