Deadeye

Hi everybody, glad to be a part of this forum.

I started flying about a month ago, soloed in one day, and have now flown my LT-40 about 20 hours (2 gallons fuel). Usually all by myself (small town, great flying field)

Anyway, I've got the flying down pat, along with take offs and landings. Since the weather is turning cold in MT, I decided to try my hand at building. I bought a partially assembled Great Planes Sportster 60. I have been working on it for a while, and am ready to start the fuse. I found a new Saito FA 100 on Ebay, picked it up for $218 including S&H. My questions are as follows:

1) The engine may be a bit gutsy for a 60 size (60-90 4 stroke rec), but I haven't a clue how to break it in properly. It's a really gorgeous engine, and I want it to last a long time, so proper break in is a must.

2) The plans call for some modifications for a 4-stroke. Things like moving the firewall back for the extra 4 stroke length. Once it is modified for a four stroke, can I ever put a 2 stroke 60 size in her? Are their adjutable mounts made that can use a 2 or a 4 stroke? Or am I just a wishful thinker? I was hoping to try a Top Flite Cessna that Saito engine would fit in nicely (scale), if I do, I'd probably like to stick a 60 2 stroke in the Sportster.

Thanks for your time,
Randy

MinnFlyer

My Feedback: (4)

I don't use Saito engines, so I won't give any break-in details, but as far as the rest of your Q's:

that engine WILL be a little gutsy for that plane, just remember that the throttle has many positions, USE THEM! That plane will fly very nicely at 1/2 throttle, and 3/4 will let you do just about anything.

As far as moving the firewall back, Yes, once it is moved back, you can still put a .60 up front, you'll just have a little extra room. And as far as the mount goes, more than likely, you'll have to replace it. Now would be a good time to make sure that you can access the back of the firewall later to remove, and reinstall the blind nuts for the mount, because the new one (according to Murphy's Law) won't line up with the old holes.

Deadeye

Thanks MinnFlyer,

I'll go ahead with the 4-stroke mods, making sure I can still access the back of the firewall.

$ircra$halot

Hey Deadeye: Good to see another Saito, they are sweetheart engines. I have a Saito 91 that started life in a Goldberg tiger 2 and worked great, this is a 40 size plane. My 91 recommends you break it in way rich, as in 5-turns open and do not run above 4000 rpm for the first 10 minutes. Mine did seem to take a long time to break in, seems it was over 2 gallons, don't quote me, but once it did there was no stopping it. It now lives in a tiger 60 and I still can find no complaints. I'm not sure on this but you will probably wan't to use about a 14x6 or bigger prop on it, that's what I am using on the 91 so you may wan't to go even bigger. I have also had this engine on a super sportster, and like the tiger 2 instead of moving the firewall back I mounted the elevator and rudder servos back in the tail to compensate for weight. Although it looked kind of funny because the engine stuck out the front of the plane about 2". You may be able to find more on Saito's web site. Happy flying Garry

jettstarblue

Big engine for that plane, you can throttle back, but that isn't always the answer, as this reduces RPM, as well as power. (5000 RPM is 5000RPM no matter how many H.P. your making)

Best to save that eng. for your other project. You move the firewall back to make room for the carb on a fourstroke, but also to keep the C.G. in range.
Break in as per the instructions.



Jetts

$ircra$halot

My experience with abc, 2-stroke engines is to run them just slightly rich during break in, these engines rely on the engine getting to a normal operating temp. to properly seat the piston to sleeve, this cannot happen if they are to rich. I have always been told, and read, if you run them to rich they do not seat properly. My preference is to run larger engines on my planes mainly because I live at 6000 feet altitude and I like extra power for vertical, and I must admit I have used the extra power to get me out of trouble before. Although prop clearance can be an issue. Also if running a bigger engine take the pre-cautions to prevent control surface flutter I.E. seal hinge gaps, and use servos with more holding power. Having the servos in the rear helps with flutter
as well utilizing shorter push rods. I do not move my firewall back because if I do decide to go back to a 2-stroke, I do not want to add unusable weight to balance. I would rather move radio equip. or battery. Mentally, I find it easier to patch the holes where the servos were, than to ad weight. just another opinion. Sorry not to good with computers yet, I'm only 46 Garry

MikeL

My Feedback: (3)

That's a great way to ruin a new ABC-type engine. Blubbering rich 4-cycling with a 2-stroke prevents the engine from reaching it's proper operating temperature quickly enough, and because of the nature of the piston fit puts tremendous stress on the engine causing premature wear and possible failure. Nice advice.

Deadeye, follow Saito's break-in instructions. Don't worry about having 10% more displacement than the kit recommends. That engine will suit the plane just fine, and you'll enjoy the heck out of the combo.

jettstarblue

SORRY
SORRY
Sorry, I got the two procedures mixed up, (like that hasn't happened before!) Perhaps I (or anyone who really needs advice on engines) needs to go to the real source of GOOD info- Clarence Lee of RCM and K.B. engine fame.- did I mention I was a dyslexic?
Whatever your proceedure for breaking(in) engines, I have broken(in) and run, and STILL HAVE most of the following- a K&B Sportster- .28, .45, .65, An Irvine .40 ABC, Two .60 Super Tigres, (ringed) a .61 ST ABC, Two .40 ST, an O.S. LA .40, an O.S. FP .40, an O.S. .40/with a Davis diesel head, a .25 O.S FP, a Mars .15 Diesel, .049 Norvel, .40 Enya, A couple of Blackhead McCoy's from the '60's, Maybe a dozen Cox products, and, finally, a TT .52 FOURSTROKE.
I HAVE ALWAYS USED 10% FUEL, WITH CASTOR ADDED TO BRING THE OIL LEVEL TO 24%, with the exception of the diesels, AND, the Cox/Norvel clan.
I have NEVER worn out any of these, and yes, they are all or have all been run A LOT! ( I have all the time in the world, and am blessed with being able to live what most modelers would concider the "dream life")- A drunk driver ran into me, disabled me and, as a result made me very wealthy. I don't recommend getting rich this way, but I did. Enough said.
Guess I'll never make "Senior Member" this way!
Have fun and, fly for life.

Jetts