w8ye

My Feedback: (16)

A guy came to the field with a OS 35FP in his Kadet Senior. It was a lengthly take off and he flew full throttle but fly it did.

Most of the old ones I've seen had old 60's or 61's on them. The newer ones had Saito 80's and 91's.

N1EDM

My Feedback: (2)

I just inherited a Great Planes Cub 40 (built from a kit) with a 77" wingspan.

Has anyone flown this on a Saito .56? I have a Saito .56 that I can put into this and would like to see what combination prop and engine (hopefully the .56 will fly it) that people are using.

Thanks for the heads-up. Looks like I had better start to order up some Cub wheels, huh?

Bob

w8ye

My Feedback: (16)

The Saito 56 will have plenty of power in the Cub unless someone built it terribly heavy.

I had a Saito 50 in a H9 80" Cub and it had all kinds of power. Flew around at half throttle most of the time. I sold the Cub to a guy who put a 46FX in it. The engine had so much power that the engine wasn't reliable running that slow. So he put a late model 40LA in the Cub. It seems just right.

One thing I've done on a slow flying plane is to use a 12 1/4 X 3 3/4 prop. The engine will rev up pretty good but I just use ful power for initial take off.

Wing-Ding

Well I maidened my Wm Super Chipmunk today powered by my rebuilt Saito FA-91S (new bearings, connecting rod, piston ring). Wow, what a difference from before! It ran smooth, idled nicely with good transition and NO TERRIBLE NOISES coming from the motor! I had a bit of a scare when I brought it in and saw a lot of oil on and around the cowl. But then I realized the nut holding the muffler pipe to the head had loosened. I retightened it and flew two more times. Great engine. Thanks for the great advice! BTW, the Super Chipmunk lands like a trainer with flaps deployed and just a bit of down elevator mixed in.

Marl

vince.b

My Feedback: (1)

My Saito 220 BK should be here next week. this is my first 4stroke ever. The plane it is going in is an H9 Sundowner.
Should be cool

w8ye

My Feedback: (16)

Marl,

Good job. Now we know where to send the Saitos to get them fixed?

Wing-Ding

Thanks, w8ye. Saito's are fun to work on. Who knows, maybe an opportunity to have fun and make a couple of bucks too?

Marl

N1EDM

My Feedback: (2)

Thanks, Jim... I have one of those props that I'll try. I'm also going to try a 11x8 and a 12x7, as those are two props recommended by Saito. Whaddaya think the power would be with either of those? The RPM's will be down, compared to the 12-1/4 x 3-3/4 but I'm wondering if there would be a power increase.

Thanks again for that note,

Bob

w8ye

My Feedback: (16)

Both of those props should pull close to the same rpm. They will both load the ole 56 pretty good. Don't know just what effect they will have compared to a 11-7 or 12-6?

show871

Have a saito 125 with problems. It flew great for 8 or so flights today with good settings.....then on my last flight decided to die after TO. on the ground it idles fine.....but at FT it rpms....and dies. will restart, then do the same thing. I checked my lines and tank, and everything seems to be fine.

It has 7-8 gallons though it

It did seem a little slow with a apc 16x6. 8400 rpm @ 5000ft

Ideas????????????

Thanks

871

Ken6PPC

The first thing I would do is check the valve clearances.

blw

My Feedback: (3)

871,

That may be a bit too much prop for the 1.25. Look for high 9k with an APC 15x6. You may need to richen the HS needle valve setting a couple of clicks. Just noticed where you are.....maybe low 9K with that prop.

Bob,

An APC 12x8 should give you around 10,500 RPM on the .56. I've used something like a 11x7 in the past, but the RPMs were really up there and it didn't perform as well. The .56 is a fairly powerful engine. Mine is on a Sig Kavlier which may be weighing around 5 lbs. It sounds like you will like the larger prop more with your Cub.

w8ye

My Feedback: (16)

For Ft Collins that rpm is not too bad.

Are your sure the temperature didn't get cooler later in the day? That will require you to enrichen the mixture to keep the engine running.

Edit: I see its cloudy there and there hasn't been much temperature drop

N1EDM

My Feedback: (2)

Jim and blw, thanks for your opinions. I hope to have the Cub in a basic flyable shape in a couple of weeks. I have an 11x9 and a 12x7 on order - they were props that were recommended by Saito. I also have some 12x6's that I can play with as well. I presume that you have the valves set pretty closely for best power. Mine are, I used the celophane cigarette wrapper trick that I learned elsewhere on this forum.

Thanks again for the opinions. Good advice,

Bob

Vinnie6

I had a problem with a loose exhaust header. Vibrating while loose actually stripped out the threads and cost me a new head. Ugh. I was told by the tech at Horizon to check the locknut on the exhaust header right after landing, while things are good and hot. If it is tightened then, it should stay. I took that advice and have not had any trouble since.

blw

My Feedback: (3)

Jim,

I meant low 9K with the 15x6. I thought the 16x6 sounded about right too for that altitude. I remember having to get carbs rejetted a long time ago for the Colorado Springs area when I lived there. The heat and altitude was tough on full scale flying.

TCrafty

Here's one for the Saito Cognoscenti. I have an Ultra R/C Giles 202 with a 180 Saito in it. I've flown it around a bunch but the 17X6 APC prop was pulling too fast. Just a couple of clicks and it was flying, forget anything over half throttle! I just replaced the prop with a 17X4W APC and fired it up for the first time tonight. When I run it up and bring it back to idle, it pops out the exhaust- a backfire. Prior experience tells me that this is from fuel in the exhaust stream firing after the compression event. That would dicatate that it needed to be leaned out as the lower-pitched prop is loading the engine less than the other. I did lean out the needles a little but it still has a little bit of a pop, not as bad as before. Does this mean I should go more or is this just not enough prop for this engine? I don't want to harm the engine but flying with that other prop was just too much. Should I drop pitch but go up to an 18 inch prop? I should say that the engine appears to run great except for this pop which occurs only when the throttle is opened and closed briskly. Suggestions are welcome. Thanks in advance.

w8ye

My Feedback: (16)

The low pitch 18" prop has 6" pitch?

Your engine may have a lean low speed causing it to backfire when you chop the throttle?

show871

Yea, Co is great

The strange thing is It flew great all day, and with the same settings, the dying at full throttle just started out of knowhere.

Is there something that can commonly go out, or come loose, or start an air leak, out of the blue????

I was at 2.25 out on the HS

871

w8ye

My Feedback: (16)

Needle settings vary from engine to engine.

What I was trying to say earlier, If the temperature drops a little, you are going to need to screw the needle valve out just a little. And vice-versa

show871

Is it reallly that sensitive to kill the motor from a 5 deg increase????? I guess that was why I was thinking it could be an air leak somewhere........just checked, all my engine bolts are tight. is there anything in the muffler that can fail that would cause a drop in fuel tank pressure????? I had my end cap come loose, then tightened the end bolt while hot that day.

thanks

871

Hobbsy

My Feedback: (102)

Show, lose the turns count and set the engine to run best each time you fly, counting turns is iffy even as a starting point from engine to engine on the same make.

w8ye

My Feedback: (16)

5 degrees Fahrenheit has made my engine go lean or rich many times.

When you run methanol (alcohol based) fuels you are faced with this phenomena. Gasoline is not so sensitive.

blw

My Feedback: (3)

You could have been borderline lean the whole time, and now it is showing up with the temp change.

p51delta

Hi Fellows!
What's the best APC prop for a FA 82. I want to try some 3D. The plane weighs just under 6 lbs. I had a YS.63 in it until now and it just wasn't quite enough. I hope it will hover now with the FA-82.
Thanks