Capt Lou

Guys:

I'm building a Sig Astro Hog Bipe. I will power it with a Saito. My question is should I power it with a FA-82 or FA-91? The 82 is about 4 ounces lighter than 91. What other considerations do you see between the engines that I should consider. I presently have a.91 on a Sig Four Star and the plane performs well. Any advice is greatly appreciated.

w8ye

My Feedback: (16)

They have about the same power. I figure the 82 will give you more flexibility in the future with other models?

RWP

My Feedback: (2)

I have a new Saito .82 on a profile and have a lot of vibration. Not sure if it is the engine or plane. This is my first Profile so maybe the plane is the problem. I have tried balancing a couple of APC 14X4W props and I don't seem to be able to get them perfect. Anybody else have trouble balancing APC 14X4W props? I'm going to try a wood prop next to see if vibration is better. Do .82's vibrate more than other Saito's? This is my first .82.

Michaelh

My Feedback: (4)

.82's are smooth. even inverted a little bump here and there. Your probably side mounted so you shouldnt be having any issues. The 14x4W balances just like any other prop.

Maybe some of the pro's can back me up but I notice a smotther idle setting the gap on the loose side. It could just be my mind playing tricks on me though.[sm=bananahead.gif]

BobMaine

Some say .82s and 1.00 vibrate more because they are bored out smaller engines, I dunno for sure. My .82 vibrated some, still does a little. Some of the vibration can be tuned out by adjusting the needle valves, there are lots of Saito tuning guides on the net, do a Google search. Some vibration may require new bearings if it doesn't go away I have been told. And some Saito's never run smooth esp. on light weight profiles. I'm still trying to get my 1.00 smoothed out, not looking good...

Tom Jones

My Feedback: (4)

Capt.Lou, I've got a 100 Saito on my Hog bipe and it is just wonderful. Plenty of power, fly mostly at 1/2 throttle, lots left just in case. Balances well also. Tom

Shubova

My Feedback: (9)

Hey Saito People,
I just bought a Saito 125 for a new plane I'm building. I have another one in a Seagull Extra 260 and it runs great. I bought it from a club member that I trust. I asked why it didn't have the venture (cone thing) on top of the carb. He said it came that way and it doesn't look like its been broken off.
The other one I run has it. Does anyone know why one would have it and another doesn't?
I'm going to the Saito web site right now to investage but wanted to see if any of you would know why its that way.
Thanks,
Shubova
[8D]

balsaeater

I think the term is Trumpet like the music instrument Trumpet

I think I read somewhere that this part is critical to correct running

Is it possible your friend was stiffed from the sales source who might have taken it off to sell as a spare part or similar round about story

Balsaeater

shzam

I have run the engine with the cowl on and off and i am turning a 14x8 apc prop. burning wildcat 15% nitro

jamesrxx951

hello all i'm a proud owner of 3 saito's and i love them all. great running engines. i am looking for some advise on my 150. it is mounted in a aeroworks yak 90 120 and it flys it great with a zoar 16/8 prop. if it is running level and i go straight up it will go almost out of sight. that thing really climbs. but in a hover well atleast the best i can do when i punch the gas it just bogs. no pull out power at all. i installed a new fuel tank and lines. made i a 3 line system so the feed to the carb is only about 5-6". i think the hs needle is around 2 1/2 out and not sure what low is but it has good smoke and transistions great. i was thinking of using a pump and seeing if that works better. by the way it is the stock exhaust. i would love some advise.

w8ye

My Feedback: (16)

You need to find a prop with a little more diameter and a lot less pitch

sodbuster 1

Have you tired running the engine without the heavy hub and nut just to rule them out?
You're putting a decent amount of weight out on the very tip of that engine shaft. Anything slightly out that far out on the shaft more than likely is going to magnify itself at higher RPM as your engine seems to be doing.
But I definitely agree with W8Ye.Profile planes inherintly seem to magnify vibration, as most Pro's will tell you just from the foaming fuel tanks on them

balsaeater

You dont say what fuel you use and what nitro content

I don't know how heavy or light is a ZOAR make of props that you use

often changing from heavy weight APC to lighter weight zinger can solve these issues as a example

A low nitro content fuel will bog more easily as nitro adds grunt at low end power to get past the bogging point
if you do use high nitro a 2.5 turn sounds very low for high nitro but more correct for low nitro like 5%
i would expect 3 to 5 turns for 20% nitro fuels nearly the double compared to zero nitro fuels


If you are budget consious and want to stay in low nitro other solutions can exist

Changing exhasts with four strokes is less likely to give any useful extra grunt at low end and will often give more power at top end but in marginal cases might make the difference

Changing props to lower pitch helps reduce bogging issues so maybe a 16*6

however diamater 16 inch is close to max for a 150 and 17 might be too much certianly my 180 is maxed at APC 18 *6 W a heavy prop slow to spool up and lots of 180 are using 16*8

three bladed props can solve some of these issues

possibly going to a 14* 8 in three blades might work or even a 15*8
( best to look to drop pitch to 6 if your plane can handle the drop in speeds and extra fuel consumption so three bladed 14*8 or drop to bigger 15*6 )

roughly a three bladed 15* 8 is equal to two bladed 16*8

in two bladed version the APC WIDE blades can be interesting
problem is the APC 14*4 W and APC 18*6 W are the only sizes I know of

If there is a 15*6W then that might do the job or even a 16*4 W or 16*6 W might also work if such an animal exists

Most modelers just throw nitro at the problem going from 10% to 20% will often cure these problems

If 80% of your flying is done at 1/3 gas you wont notice the extra consumption so much possibly by 10% to less than 20% so a ten minute tank might drop to ~8 minutes running

If most flying is at full gas then expect the run time for the same tank to drop by a whopping to 1/3rd so from 10 minutes to more like ~6 minutes

However staying with low nitro and going to bigger diameter prop with less pitch will bump up fuel used by ~10% plus but it will be cheaper low nitro fuel

Most good hover type props are very low pitch reliitve to diamater
examples are 14*4 or 18*6 which are less than the 1/2 square types such as 14*7 or 18*9
deep pitch often cuases bogging from the air swirl around prop slipping of the deep pitch props and creating huge drag even though engine is working perfectly the sudden massive extra load from stalled blades or semi stalled can bog the engine
..........if its a very heavy prop
......or too deep a pitch prop
.......or low nitro fuel
....... or very heavy airframe
..... or hot engine from lack of cooling in hover mode
.......or fuel starved or semi fuel starved
........or underpowered for the job
......or working at very high altidudes
.... or bad fuels


Hope some solution works for you

I myself prefer to throw low end grunt tractor power BHP and low nitro at the problem so a 90 to120 class plane will get a Saito 180 and and a 120 to 180 class plane will get a Saito 220 all running on zero or 5% nitro fuels
I generaly reach for the biggest diamater prop with the smallest pitch and fly around mostly on 1/3 gas and fuel cost and consumption isn't to bad for example less than 1 onz per minute with the 180 saito

Ralf

BobMaine

It isn't a Higley heavy hub, just the lightweight aluminum spinner one. It's some kind of harmonic vibration thing, it only does it at 5000 rpm + or - a few hundred. And the tank does foam like the first pour after the beer keg is opened. Right in the hover rpm area too, the whole plane shakes and the Monokote really drums. If we had a few more like that we could start an RC band.

Some people are putting metal or carbon fiber engine mounting rails on their profiles helps a little I hear.

I wonder what goes wrong in the manufacturing process that causes a few Saitos to shake badly right out of the box and most to be fine.

I've ordered a set of bearings, if that doesn't fix it I'll have it "put down" maybe do it myself with my 9 mm....

Hobbsy

My Feedback: (102)

There isn't anything wrong at all, it is simply tortional impulses acting on a thin profile fuse that fleses easily, there's no great mystery. You may have to find a way to stiffen the fuse or put a two a stroke on it and even the two stroke will shake it but down closer to idle. A heavier engine or a heavier prop my dampen the impulses some but they will not go away.

the pope

I like the mother on crack answer better It might just be me but I think it sounds a bit more scientific. Now wheres my bong? cheers the pope and happy hallucinations.

Hobbsy

My Feedback: (102)

Harvey, I only seem to have the instructions for the older .40 with the rocker arm covers, let me know if that will help.

Michaelh

My Feedback: (4)

APC's production list. Dont use Zingers or Zoars they load the engine. They are light but that can be a setback at times.
http://www.apcprop.com/cgi-bin/store...c=6a&product=+
I feel a 16x4 would be too small BTW

Hobbsy

My Feedback: (102)

Bob, here is my kombat 60 with a Laser .70 on it and the very same phenomena occurs at about 4,500. You think it will shake the wing off.

beaver180

My Feedback: (10)

SAITO 150S BEARINGS

Hi there all,

I have a Saito 150 S that requires new bearings.... can anyone please tell me there sizes and/or the part numbers off the bearings???

I have to go to local specialist bearing shop to get replacements quickly.

Thanks for you help in advance, Paul

w8ye

My Feedback: (16)

Front bearing MR6000 -2RS 10mm-26mm-8mm

Rear Bearing MR16003 17mm-35mm-8m

beaver180

My Feedback: (10)

Dang your awesome! Didn't expect such a fast reply.... many thanks!

The front bearing has a seal on both sides, is this right??

Cheers, Paul

shzam

hobbsy, why would a saito 100 lose compression after running a half of tank of fuel through it. I am running 15% wildcat with a 14x8 apc prop

blw

My Feedback: (3)

shzam,

Are you checking compression with the throttle closed?

A1

My Feedback: (2)

I'm wanting to purchase a new Satio. Without going thru the 466 pages. What are the pros and cons between a 120 and the 125?
Thanks.............