Fred L

My Feedback: (2)

i got it at a flea market with engines, servos and batteries. came with 2-.75 GMS 2-strokers and landed kinda fast cause i had to keep the idle up so the engines would't die on me . saved up my beer cans and bought 2 saito 91's in hopes that the lower idle would produce a slower landing. if that don't work i'll cut in some flaps somewhere on it . both engines have been initially started on a test bench and one has been mounted . one more to go and a throttle connection relocation and it's off to the field to fly

Rudolph Hart

If you think the fuel tank level i9n relationship to the carby looks ok and have checked all the obvious things then i would wind the main needle out about five clicks and fly it.You can always land and lean it if you think it is;nt pulling the revs it used too.

SrTelemaster150

Since the TDC ignition sequence is 180/540* one of the cams should be timed 90 (cam degrees) from the other when the crank is held @ TDC on one cylinder, BDC for the other. I'm not sure why the difference is 105*. It may be due to a different (relative) tooth engagement @ 180 degrees of crank rotation?

I'm also a bit confused by the (PDF) manual instructions for the 182T as the text references the veiw from the rear while the illustrations show a frontal view & the illustration #s seem to be bassackwards. as referenced in the text.

If you think the uneven firing horizontal twins are confusing, they don't even publish the cam timing sequence for the 100 & 200Ti (inline 30* "V" twins) in the PDF manual.

These have counter-rotating cams lobes (the cam gears still rotate CW when viewed from the front, but since they are reversed front to rear, the lobes rotatation is actually reversed) due to the fact that the rear cylinder has the cam (gear) loctated facing the rear.

Fortunately, everthing I have seen indicates that these are even firing twins (both pistons hit TDC @ the same time) so it would be a simple matter of setting one (front) cylinder @ TDC via the dot & rotating the engine 360* to time the rear cylinder likewise.

The front cylinder of the 200Ti uses the same cam as the (left cylinder) 182T. The rear cylinder cam has an exclusive 200Ti part#. That does not make sense to me as the front cylinder should use the garden variaety cam lobe rotation.

Hobbsy

My Feedback: (102)

The cams are not symetrical, so if it rotated backwards it would have to be ground backwards.

w8ye

My Feedback: (16)

The rear cam from the 30 degree vee twins is used to run a single cylinder Saito in reverse

SrTelemaster150

Exactly.

SrTelemaster150

That would be great for a P-38 as you could then mimic the full scale counter-rotating engines. (if you could keep the counter-rotating pusher prop from lossening the prop nut)

I realize now why the front cylinder uses the 182 left cam. Both the front 200Ti & left 182T use a cylinder that has the intake & exhaust ports reversed.

That might also explain the 105* timing difference. for the left 182T cam marks.

fly boy 2

My Feedback: (1)

I have been told that if my low speed needle is too rich it will cause this to happen.  Have any of you heard of this?
Thank you

rowdyjoe

My Feedback: (9)

hello to the group.  haven,,t been able to log in due to site virus issue.  

AJsToyz

Dave,

Do you have a 1.25? If so what size props have you run on it with what ind of results? Really interested if you have run a Graupner 15x8 3 blade on anything and what other props you compared it to.

This is actually for my little Mintor but I know you have run a lot of props. I can run a 16x8 MA K series up around 8700 rpm's. Looking to load it up a little more. Maybe bring the rpm's down to about 7800-8200.

I was trying to search the forum but it won't let me search re:deleted.
Andy

N1EDM

My Feedback: (2)

Hi Hobbsy,

Just an update on my login issue (and others who have the same problem, I think). I still cannot log in from the email link. I have to come in from the Forums front page and it dumps me into the first post.

Has anyone been able to figure anything out about this? I've unsubscribed and resubscribed several times to no avail.

Thanks,

Bob

orthobird

My Feedback: (1)

hello, i need some help.  i need to explain in length what has happened.  please do not hesitate to ask questions if i confuse you.  i purchased a brand new saito fa 125 from horizon hobby 2 months ago.  i installed the engine into a revolver 70.  i did do the break in procedure described on this forum with 10 minutes at 2000 rpm, then 10 minutes at 3000 rpm, etc..., using my tach.  on the first flight, this plane flew real real fast.  i was using a 16 x 6 prop.  this plane had so much power, after 6 minutes on the maiden flight, the plane, all of a sudden lost control, and it crashed.  the rudder servo had plastic gears, and the plastic from top gear snapped at junction with servo horn.  the plane was totalled and engine suffered a bent crankshaft.  However, this was not discovered at first.  allow me to digress.  i bought the same airplane, again, gP revolver 70, and redid everything, but this time better.  Life A123 battery pack, JR 8711 servo for rudder with pull pull, voltage regulator, all MG servos for other surfaces.  two servos for elevators also.  right after completing installation, i also reinstalled the saito FA 125, there was, at the time, no obvious damage to carb, cylinder head, pushrod tubes, etc...  however, after i installed the spinner and the prop, i turned the prop and noticed that it was not spinning true, and at this point, i diagnosed the bent crankshaft.  now, i had to remove the engine from the brand new plane.  to remove the engine, i decided i would remove the carburator throttle lever, since the pushrod was attached to it, and this in turn was attached to servo in board.  I did not want to take so much appart, so i decided to remove the lever.   in doing so, i inadvertently began to turn the visible "screw", until i then realized, hey, wait a minute, this is the low speed needle, ouch, i then found the hex head screw which then removed the lever.  but now, i had removed the setting of the low speed needle.  so now, back to my dilemma.  since engine has been reassembled, i have flown plane about 10 times, however, it does not have anywhere near the same power and speed as it once had.  i am turning a 16 x 6 prop at 7500 rpm.  today, i flew plane twice.  after first flight, i decided to play with HSN, and i leaned it just slightly, using tach, i saw it was now turning 8200 rpm, i was excited.  the moment bird went up in air, i knew something was wrong.  plane was way underpowered, and within 7 minutes (once it overheated), the plane would stall if engine was at WOT, so i brought throttle to 1/5 power, and it stayed on enough to let me land the plane.  so i am asking all the saito brains, the ones with the most experience, what do you believe is the problem?  do you think i need to open the LSN some more, and hope to get the 9000 rpm back?  or do you think something else is wrong.  i am using 15% nitro fuel and it is brand new, just opened the bottle today.  i have also checked the valve clearance, and all fo the pushrods are fine, they are not bent.  also, the engine starts up immediately.

N1EDM

My Feedback: (2)

When you put in the new Crankshaft, did you disassemble the engine completely or just disassemble what was needed? My reason for asking is that I'm wondering if you happened to take off the rocker arm covers? If so, did you notice if the pushrods were nested in the rocker arm properly? Did you re-adjust the valves? You should barely feel any play at TDC, but you should definitely feel them rock a little bit.

Just my $.02

Bob

orthobird

My Feedback: (1)

hi, thanks, yes, i did all that, and when i reassembled, i did re do the valve clearance.

Rudolph Hart

I'm not an expert,you may be a tooth out on the cam timing,but most likely from your description above your needles arn't set properly.Go back to the factory settings and start again it only takes a few minutes,good luck.

SrTelemaster150

I agree. I suspect that the LSN is so rich that the HSN setting won't compensate.

orthobird

My Feedback: (1)

Hi, thank you for advice, i will check this today. one question, however, if the timing was off by one tooth, could the engine still rev up to 8200 rpm?

alan0899

G'day All,
Does anyone have any good or bad reports on the Saito FG21, I'm thinking I might sell my FA125 & get a FG21 for my Phoenix Spacewalker.
Any comments would be welcome.

Cheers.

Hobbsy

My Feedback: (102)

The High Speed needle operates in a fixed/unmovable seat, its setting cannot effect the Low Speed needle. The Low Speed can effect the HS needle if you get the LS needle too lean, When the LS needle is too lean you won't be able to richen the HS needle because too much of the, "cats eye" is covered by the LS sleeve. Its important to set the HS needle first.

Hobbsy

My Feedback: (102)

I know that those are Saito engines but there is a lot of discussion on them in the Gas Engines forum.

orthobird

My Feedback: (1)

great, thanks,, that is what i thought, maybe too lean on LSN. i also noted when plane flew, there was very little smoke trail, usually, with nitro, if it is rich, it will leave a faint smoke trail. great, i will fix it and update you. hopefully i can get back the 9000 rpm

orthobird

My Feedback: (1)

i have an fg 36 and i love it. what a engine, and it sounds great! never had issues with it, starts up easliy, and the best part is that the fuel is so cheap and no oil mess. however, beware of cowl anf the engine carb intake. some of the gas engines with rear entry carbs have problems when you do not have adequate air circulation. i did have this problem when the engine was installed in a super decathlon. however, there is a guy, tinkerman tim, on youtube, he has saito fg 21 on a p51 blue nose, and he had to build an air intake specific for this plane/engine commbo, once he did that, engine worked great.

blw

My Feedback: (3)

You got that part right! Most people crank the the HS needle around until they see a thick trail of smoke and then they are ready to fly. I never go by smoke on a Saito for tuning.

Hobbsy is suggesting that you peak your HS to absolute peak and leave it there. Don't lean it any. Tune the ls. After every couple of adjustments on the ls, go peak the hs again. Repeat as necessary. When the ls is set, then peak the hs again and lean it a few hundred rpms. Remember, it may take a couple of trips around the field with you listening closely to the engine to get it exactly right. If your tuning is right on the button on the ground, it may lean out a fraction while in the air. Just land, tweek, and listen again. Like the man on TV says, "Set it, and forget it."

orthobird

My Feedback: (1)

tunrs out the LSNwas too lean.
i was able to turn it out 2 1/2 turns, and now it sounds better. max rpm is 8400 with a 16 x 6 evolution prop.
i am getting a 16 x 6 apc prop from tower hobbies, should be here soon, then i will re do test and flight. the apc 16 x 6 was the orginial prop used on the maiden of the revolver #1 (maiden flight)

orthobird

My Feedback: (1)

tunrs out the LSNwas too lean.
i was able to turn it out 2 1/2 turns, and now it sounds better. max rpm is 8400 with a 16 x 6 evolution prop.
i am getting a 16 x 6 apc prop from tower hobbies, should be here soon, then i will re do test and flight. the apc 16 x 6 was the orginial prop used on the maiden of the revolver #1 (maiden flight)