charlie1960

http://www.horizonhobby.com/Products...rodID=SAI10023

but as luck would have it, OUT OF STOCK....[:@]

There is a guy that straightens bent cranks, in Georgia i think.
I'll have to contact my friend and see who what where and when.
He had a crank straightened on a 125 i sent to him.
Was very pleased with the result.

He goes by JimmyHoffa in RCU.

earlwb

You could try the guy in this thread here, he straightens crankshafts for people. Flyboy_Dave.
http://www.rcuniverse.com/forum/m_69...tm.htm#9840965

charlie1960

Have you guys seen a Saito run with out pressure to the tank??
Last week end i took my Bolt out for a spin, the Exhaust pipe broke off against the head.
Didnt notice this right off, untill a close flyby.

had made several circuts around the pattern, saw something flapping in the wind, and on a
slow close flyby could see the muffler swinging in the breeze. throttle up without hesitation.
I made two more circles digesting this. I set up to land,called out a possible dead stick
and landed and taxied back to the pit. the engine never missed a lick.
I did notice it would sputter at WOT, but at 3/4 and below ran flawless.

Now. The day wasnt over. I had my son bring me a flexible exaust pipe i purchased some time ago.
I installed it after cutting it off to approx. 4 inches, Man what a sound. not loud, just different.
wound up richening the HSN a half turn, and the rpms and power showed quite an increase.
On the second flight, this springy pipe broke off too. its was very lively with vibration.
BUT, i didnt see THIS untill i had landed after a several minute flight.

And if anyone is familiar with the skybolt arf, you know how far back the tank sets.
I had no idea the little engine would draw fuel like that. Would not have beleived this if i hadnt seen it myself.
A couple guys shook their heads, said that shouldnt have happened.

So now, i am in pursuit of the perfect ultimate straight exaustpipe hedder

hsukaria

It seems to me that Saitos are prone to broken muffler/head threads. I guy at our club had the same problems. Do you suppose it is a design flaw?

retransit

My Feedback: (18)

At last count, I have 14 Saitos. None have ever had their exhaust threads come out or had their mufflers break. The only time I had a problem was when I crashed, and that was only the valve cover and a cast motor mount.

Bob

charlie1960

its only 4 yrs old.
i guess something needed to happen.
i suspect prolonged vibration set up metal fatigue.
it broke cleanly right against the jam nut.
wasnt hard to remove at all.

was merely facinated that the engine continued to run and ran well.

w8ye

My Feedback: (16)

A guy had broken several muffler headers on his Saito 62 GK on a Slow poke whereas we had tried to help him in the forums. Finally, he resorted to selling the engine in the RCU Market Place. I bought this engine from the RCU Market Place over three years ago.

The engine sat in the shipping box for about 9 months but I finally got it out and mounted it on a Ultra Stick 40. I installed a APC 13 X 6 prop and away I went. I didn't even have to adjust the needle valves. I've been flying it for over two years now and it has well over 100 flights. I've failed to find any problem with the engine. It still has the same muffler and header that came on the engine. needless to say, I've used this engine more than any of my other Saitos in this time.

Only thing I can figure is that the guy had used an aluminum spinner without cutting out the slots to clear the prop. The spinner was all bent from the pressure. This must have been out of balance? I have the spinner that he sent with the engine but feared using it.

retransit

My Feedback: (18)

Vibration is the culprit in a lot of problems, including lean running on bubbled fuel. As far as the spinner is concerned w8ye, you probably hit it on the head.

Bob

w8ye

My Feedback: (16)

There was another person in the forums with a Saito 125GK that vibrated terribly and made a double noise.

 He eventually talked me into running it to see what I thought.

He had bought the engine used. I found that the previous owner had used a APC 17 X 4W prop. The hub on this prop is too thin to use on a Saito 125 without using a spinner backplate between the prop and drive hub. On this engine, the prop was not actually secured by the prop nut because of the step up in the size of the crankshaft, the front washer was stopping against the step and not the prop.

The prop drive hub was worn smooth on the face that is supposed to contact the prop. The prop washer was all worn on the face against the prop.

I told the owner to replace the parts and use a 16 X 6 prop. I never heard any more from him.

retransit

My Feedback: (18)

w8ye, we seem to be going in the same direction.

Last week I mounted a 20 X 6-10 prop on an Byron RV-4 with an O.S. 3.2 four cylinder (original prop from the seller). As I cranked down the prop nut it snapped. The prop hub, being the width of a 6 inch pitch prop, bottomed out on the spinner backplate, causing a fracture of the internal nut that screws on the prop shaft. I replaced the piece and went with a straight 20 X 10 Xoar prop which is considerably thicker.

Bob

w8ye

My Feedback: (16)

Me and 6-10 pitch props never got along anyway.

At least you were aware of what was happening and took corrective action.

I think a 10 pitch prop is right for a RV-4.

Firemandave

My Feedback: (1)

Hello Dave here!

  I'm new to R/C U and a new Saito owner. I just bought a 91 to replace a GMS engine on my Black Horse Model T-28 Trojan  and was reading its not going to be a fuel and go engine. Can you long time owners give me some pointers.  Thx!

hsukaria

All this info about props touching the spinner and being loose behind the prop nut is very helpful to me since all my other engines are smaller. My first jumbo engine is this 1.8 Saito I just bought used. I can see where the muffler could break from all the excessive vibes.
Thanks

w8ye

My Feedback: (16)

There's nothing unusual about the Saito 91. Just prop it right and don't get it too lean and you will be happy.

The Saito 91 is sort of the Chevy small block of the 91's. It is smaller and lighter. It likes a 14 X 7 prop.

Beej

Hi Dave,

Welcome! There are many more experienced people here than me but I'll add a reply. Unlike, say, an OS 46 AX it's not a question of running a few slightly rich tanks through it out of the box which some do (but I always carefully follow the manusfacturers break in instructions anyway.) For the Saito though it's really simple. Before first start you might want to remove the rocker covers and drip a little light oil down onto the pushrods, squirt a little oil into the crank via the nipple and turn it over by hand to make sure it's well lubricated before first start. You really need a tach for the break in. Follow the Saito instructions carefully - that is, first run v.rich at no more than 4000rpm (use the throttle). You will burn through 500ml of fuel in just minutes at this stage. Let the engine cool and take it up in increments of 1000 rpm for each run from then on, first by using the throttle (keeping in rich) and then when throttle is wide open, by leaning it out. After you have approached peak rpm (use recommended prop sizes) back it off by 300rpm and dont run it leaner than that. So, that's it. When you have 4 - 8 litres through it is well and truly good to give you may years of fantastic running, although many see improvements accruing beyond that. You may want to check the valve clearance at the end of break in (it's easy) and after that - leave them alone unless you suddenly get problems. Setting the idle is deceptive - unlike 2S engines the Saito can transition really strongly even at a stupidly rich setting (which is the factory default) - follow the instructions - set the high end, lean it a 1/4 turn at a time until engine quits upon rapid transition from idle, then back it out in 1/8 turns until it's smooth. Unless you do this you may find that your Saito will drink more fuel than the space shuttle! I try to break in on a stand, just for convenience and to really annoy the neighbours. Anyway, hope this has been helpful. These pages have all of this information throughout, and it's a great forum. I found the following website an fantastic "one stop shop" for all of the above!

http://saito-engines.info/index.html



happy flying

Beej

Beej

p.s. sorry - a bit ambiguous there - when setting idle, I obviously mean turn the low end adjustment 1/4 - 1/8 turns! Leave the high end alone. If you are breaking it in on your airframe as you get the low speed mixture near optimal you will see the idle rpm rise a bit - just add a few clicks of throttle trim and keep going.

Beej

lopflyers

My Feedback: (12)

Helpppppp. This morning I tried starting my Saito 62 and it didnt start. I changed the glow plug and now while it starts it smokes.
I turn it off inmediatelty.Can the wrong plug make it smoke? Can there be something else wrong? Is an F plug good?

earlwb

Sounds to me like it was flooded, and that killed the glow plug. Then when you put in a new glow plug, it was burning off the excess fuel and oil that had accumulated.
F plug is OK. It probably just needs to be run a while to get it to clear up.

lopflyers

My Feedback: (12)

The thing is that I took a plug from my box that was not in the package so Im not sure if it is an F or not.
If it is not, can the wrong size plug make it smoke? I dont think but I am new in the hobby.

w8ye

My Feedback: (16)

Most four stroke plugs have distinctive look - notice the protrusion at the bottom?

triumphman49

My Feedback: (149)

Hey All . . . you too W8YE , Wonder if I'd get by using a 10 - 12 oz tank with a FA60T in a Smith Mini? . . . . Or if I'd really need to go larger? Would expect moderate aeorbatics with plenty of mid range flying and about 12 min or so flights. Many Thanx

Mike Brennan
Club Saito #723
T-Man49 in Al

w8ye

My Feedback: (16)

I think you will be in fine shape

triumphman49

My Feedback: (149)

Sounds great W8YE, fuse has slowly come together, working on wire next - gear, cabanes, etc. Thinking about cg & placement of all goodies & such. Need tail feathers done so I can better estimate. Again Many Thanx

Mike Brennan
Club Saito #723

clytle374

I've got a 100 going under a cowl. I need some sort of extension, what do I do with the high speed needle so I can get to it?

Thanks
Cory

w8ye

My Feedback: (16)

There's a hole in the center of the needle valve to stick a piece of pushrod wire in. There is a set screw to hold it. Bend an ell on the end of the wire.

You can also attach a small wheel collar on the end.