Flyer95

My Feedback: (1)

Some update, I had some troubles with low idle on my Saito220 mounted inverted. I could see that when the glowbattery was remove it would slow down too much and eventually die. But I could not lean the idle mixture anymore.
My guess was that the compression is too low to accept the 20-30% nitro fuels. So I simply dismantled the engine and milled 0.5mm of the crankcase where the cylinder is bolted to. Now it runs great at idle without loading up and it is still smooth. My fuel is 10% nitro and 15% oil syntetic/castor blend.

Rudolph Hart

My 220 arrives shortly and will be inverting it.Did the removal of case material affect high end rpm performance and if so how? are you running an onboard glo driver yet?

Flyer95

My Feedback: (1)

I could not notice any major changes at high rpm but the modification did improve the idle by about 500rpm lower than before. No, I have never used an onboard glowdriver.

Flyer95

My Feedback: (1)

I was out running my OS200fs and Saito220 and got some real rpm after landing each plane.
APC18x6w and fuel containing 15% oil syntic/castor blend and 10% nitro for both engines.
Saito220 8600rpm
OS200 8100
So the different is about 500rpm which is noticeable in flight and vertical performance. The OS runs much more quiet but the Saito unloads better in flights. Both engines are very reliable and uses little fuel about 0,25-0,3 litre per/8min flight.
The 15% oil seems to be plenty for the OS200. Probably because of the recirculating crankcase oil? Does anyone have an idea about how much more oil the engine gets because of the recirculating system?

GarySS

My Feedback: (13)

It's not a very large vent hole, but when it comes off while on the test stand it sure creates a big mess!!!!!!!.

mk1spitfire

i've been offered a fs200, I plan on putting it in a sundowner

worth getting?

Flyer95

My Feedback: (1)

both yes and no. Yes because the engine is very well made, very good fueldraw and reliable, have loads of torque and very quiet almost like an electric motor. No because mine dont like to rev higher that 8000rpm or it sounds like it is preigniting. I actually dont know the reason for this yet.
With a highpitch prop. like the APC 16x12 it might give the speed you need for the sundowner.

mk1spitfire

humm interesting. i notice the 120ax puts out the same power as fs200 and lighter. I wonder if that would be a better bet, lighter too.?

Rudolph Hart

You've answered that question re your comments.This is a comparison between two fourstrokes mate

Flyer95

My Feedback: (1)

I dont know which one would be faster? If you prop the OS200 for about 7500rpm static it runs great airborne. The 120ax needs a smaller prop like the APC14x12 and turns about 9000rpm from the memory.

Have been out running these engines some more. I have come up to the conclusion that these engines have very high torque that can be used for better performance with a larger prop. So now I run a APC 18x8w on the OS200 and APC 19x8w on the Saito220. Both engines turned 7400rpm richened down for 8-10min flights. Vertical performance and speed is very good for the 70" Edge540 and Yak54.

Jimbo750

I have0S 200 (non pump) in my H9 Funtana X100. with a 18 x 6 it hovers on one third throttle. Best thing is very low mess. Much less oil than my Saitos. I will buy a second one.

Flyer95

My Feedback: (1)

I also went back to the apc 18x6w for both these engines as it seems to be the "best" overall prop for these engines as it pulls nice and is durable for the chicken stick starts. I could not get low idle on my stock OS200 which is inverted in a 70" Edge 540. Would load up when removing the battery so i removed the headgasket and also raised the compression in a CNC-milling machine at my work. Now it holds up the heat much better at idle. Its a pity both these engines seem to have low compression stock. I also tried a Sonic Tronic 4-stroke plugs instead of the OS-F and it seems to be slightly better at idle.

Do you have yours inverted in the X100 and how is the idle? What fuel do you use?

Ken Cz

I have an OS 200 mounted 20deg. off true inverted and it runs great at idle with a Sullivan On-baord glow driver. Using the APC 18x6W and Powermaster 15% nitro- 20% Syn. Patternfuel - on a 25% Magic Hands Yak from Troy Built Models. Plenty of power for this bird!

Ken

Flyer95

My Feedback: (1)

I like the OS200 because it is lightweighted and runs very quiet. 
Last week I had to change the bearings in my Saito220 because the stock ones had som radial play. When changing bearing i found that original bearings had one ball less than the one i was putting in. Thats probably why they get radial play efter only 3-4 gallons been thru the engine. Performance went up after the bearing change. 

mm

hello all,

well, my os 200 with pump after 4 gallons with 10 % nitro cool power and os type f, doesn't well idle...i'm a little disapointed..it isn't like my yamada 140 limited...

Stéphane

scoobiedoo

I have gone though two rear bearings the original one had 10 balls the second one was a stainless steel which was sealed I removed the seals and had 11 balls in it,
Waiting for a new one to turn up SKF type will be interesting to see how many balls this one has and if its sealed or open, and how lone it lasts!
I still think the rear bearing size on this engine is to small, I believe it’s the Saito 180 size and that they should have gone up a size.
You can soon tell when the bearing going as the power drops of and it sounds like the tappets are rattling.
Also I can only get a good low tick over with an on board glow supply no matter how hard I try, my OS 200 no glow supply required you can see the prop lazily plopping over miles better than the 220.
I must NOT TWEEK THE MAIN NEEDLE WHEN IT’S A WARM DAY I must richer it if anything must try harder. LOL

Rudolph Hart

Are you using after run oil?

scoobiedoo

yes i do, never had any problems in the last 40 years with bearings packing up.

Hobbsy

My Feedback: (102)

Here is a shot of my Saito 2.20's idle with a Just Engines Jen-C/Biela 20x6 @ 1,835 rpm. The plug is a Fox Miracle Plug. If a Saito won't idle slow the LS needle is too rich. It would idle at about 1,750 with the larger carb. Also showing difference in weight between stock muffler and the TurboHeader. This all moot since the OS 2.00 and the Saito 2.20 are neither one in production.

scoobiedoo

My idle needle is 1.8 mm from the face of the plastic throttle arm to the head of the brass idle screw head if I screw it in another 1/8 of an inch if that the engine will stop so it cannot be to rich on the bottom end, it is fitted with an OS four stroke plug. Duraglo contains 9% E.D.L. (synthetic oil) and 6% castor oil plus 10% nitro
Also tried QwikFire An 18% oil content (13% EDL and 5% Castor) with 10% ( see my models) done a couple of twins in the 70/80s

I will run it rich so not to wreck the rear bearing

Hobbsy

My Feedback: (102)

No need to worry about the rear bearing, there is this much oil in the crankcase at all times regardless of how the needles are set.

leonardor

Hi Hobbsy,
did you noticed a remarkable increase in power using the large bore carb on the saito 220? Is it worth the investment or is mostly beneficial for the pressurized fuel system (pump)?

Hobbsy

My Feedback: (102)

About 200 rpm, the Saito pump system was a Mickey Mouse setup in my opinion and after years of being cautioned to never restrict the vent, you're supposed to restrict the vent to pressurize the tank. I opted for an IronBay regulator and check valved muffler pressure. This made for a clean, linear mid range. I sold that engine to C&H Ignitions.