w8ye

My Feedback: (16)

The scew above the throttle arm with the spring should be the "idle speed" adjusting screw

w8ye

My Feedback: (16)

The screw above the throttle arm with the spring should be the "idle speed" adjusting screw

w8ye

My Feedback: (16)

Here a picture from the rear of Kmot's very early model plain 120. Notice the air bleed carb. There were like three variations of these early carbs

parker

Here are some pics of my engine

w8ye

My Feedback: (16)

You definitely have the early model cam with the straight cam followers

Your carb is not the air bleed one but is somewhat older.

Which bearings your engine has would be a tale tell of the block?

I had one once that was all mixed up. It was an early engine with a late cylinder.

parker

The bearings are sealed in the front and open ball in the back, the bottom line here is the intake manifold if the 150 will fit I can rebuild the engine if not then I am out of luck. Parker

w8ye

My Feedback: (16)

The old plain 120 had a R6-2rs bearing in the front it had a .375" id .875" od .2812" thick
In the rear it had a 6902 bearing 15mm X 28mm X 7mm thick

The 120S had a R6000-2rs in the front that was 8mm X 26mm X 10mm
In the rear it had a 16003 bearing that was 17mm X 35mm X 8mm

parker

The front bearing is a 6000LU and the rear is a 6903 Parker

w8ye

My Feedback: (16)

I've been trying to look. The old original engine was had a brass sleeve inside that was chrome plated for a cylinder wall. You should be able to see brass at the bottom of the cylinder?

The 120S had the chrome directly onto the aluminum

The valve seats in the early one were brass whereas the 120S just had chromed aluminum valve seats

I cannot see enough of your intake manifold to compare it with the present one?

I also don't have any old examples around me to compare with.

Yours is a later model than the early model I had in the picture but it's not a late model engine either.

w8ye

My Feedback: (16)

A 6903 bearing has a 17mm ID X 30mm OD X 7mm thick

w8ye

My Feedback: (16)

I'm of the opinion that your engine is a later model of the plain 120 engine?

But there are things not adding up like the bearings are not the right numbers?

parker

I checked the bearings and the front is 8mm thick, 10mm id and 26mm od the rear is 7mm thisk 17 mm idand 30 mm od Parker

w8ye

My Feedback: (16)

I only have a 150 in front of me which should look much like the last of the 120S' made?

I was trying to look at the picture of your intake manifold and the position of the screw for the carb doesn't look right but it could be a distortion caused by the camera/

Looking at my 150 with the part of the intake manifold that goes in the cylinder head pointing away from me and looking down on the carb flange, the carb bolt holes are at a 45 degree angle compared with the direction of the part that goes in the cylinder head.

parker

I compaired these pics to the 150 that you sent me and the mounting holes arent the same also notice that I had the intake manifold mounted backwards in the first set of pics so I rotated it 180 Parker

w8ye

My Feedback: (16)

I see your bolt holes are not the same as the new one you would get from Horizon.

Your carb is mounted skewed. It also has a different bolt hole orientation from the current new carb

But, there's no reason why you cannot drill the holes in the correct place to make your carb straight across.

The only problem I can see with that is that one bolt will be up under the intake manifold elbow. You will need a shortened allen wrench to fit in the screw.

mred33

I used a plastic spinner for awhile on my 100, but never again. It back fired once and blew the spinner apart. I now use Tru-Turn spinners only and will never go back to plastic.

I tried the different props this weekend and it seems that the 15x6 with 30% Heli fuel works the best out of the three I tried. Very good vertical and plenty of speed without ripping the wings off. I had to order some Castor for my 15% fuel, so it looks like I won't get to use it until next weekend.

I have a question on rebuilt engines. A friend of mine put new bearings and a new ring along with a new rod in his 100. Should you re-run the break-in again like a sort of new engine, or just run a tank and go fly it? I am wondering mostly about the new ring and rod more then the bearings. Thanks for the help.
Ed

w8ye

My Feedback: (16)

Run a tank and go fly

A back fire can blow up a tru turn too. I've seen them spread out like a disk on a 100

nitrofevr

HI all im not new to rc just really late to rcu. I have 3 saitos, 1.25, .91s, .56. My 91 has about 40 gal. of fuel through it and my 56 has about 15. not yet ran the 1.25 but it looks good in the showtime 50 to me there is no other 4 stroke than saito. Could someone plz point me in the right direction for the most static thrust prop for my 1.25? not worried about speed but thats a byproduct i guess. And what would be a member #?

blw

My Feedback: (3)

I have a 1.25 and no idea of static thrust. All that changes once you get it moving in the air.

For you, the number is #558. Welcome aboard.

nitrofevr

thank you blw. but static thrust is very relivent for hovering....but you can make a brick hover with thr right engine just want the brick to hover the best it can

parker

I want to clean my Saito 120. I heard that you can put the parts in a crockpot with antifreez?

w8ye

My Feedback: (16)

You cannot boil the antifreeze. It can just be hot

boogermancan

i have a 60 twist witha saito 125 swinging a 17x6 apc prop its real happy and idles real well below 2000 it gets to kicking below 1750 max tune is around 8700 rpm i turned it down to 8200 i like things a little fat side the 17 inch props putts plenty air across the wings for controll when hovering the motor is not a snapy spool up with it but it idles so good . it flys at 1/4 throttle and hovers at less than half throttle
but this is imho only ..... and now for news on the tango i got last week

w8ye

My Feedback: (16)

A fellow I fly with has a Twist 60 with a Saito 125. He was running a 15-8. He really likes it. Had it for two years now.

parker

Thanks, I thought that this might have been a joke but now I will try it also thank you for all of the info on my saito 120