w8ye

My Feedback: (16)

If you still have the plastic back plate, you also want to change to the aluminum back plate and carb mounting screws from a Saito 91 or you will continue to have trouble.

mike early

I found this post in 2006:
http://www.rcuniverse.com/forum/fb.asp?m=4528671
We cannot really call it new, I guess...

If the upgrade was made before 2006, and the engine was bought 3 years ago, can we assume the engine came with the "upgrade"?

FNQFLYER

Gee a guy goes awa for a few days and catching up on the postings becomes a real chore.  But all good stuff. A few comments
1/ I always use an electric starter on ALL my engines, a finger broken in three places and 2 fingers with prop cuts about 2 inches long have yet again educated me re the virtues of keeping fingers out of props (A saito 65 was the culprit)
2/ Using electric starters on LeRoys revenge (Cox 049) is interesting cause the motor once fired up spins faster than the starter
3/ At the O/T Nationals next year in OZ (at Cootamundra in October Old Fart) I expect to see a great increase in Saitos on the field, there is a lot of interest in the 56 / 62 combinations and 65's have become scarce so more valuable
4/ Lastly in discussing 4 strokes no body talks about YS, the 53 and 63 (no longer produced) were great engines so much so that rumours our of Japan would indicate that Saito is looking to fill that void.  If so I for one would be in "hog heaven"
More later guys, got to get back to test bed model I am building.  Rainy season is trying to get here so must get the project finished ASAP  

blw

My Feedback: (3)

Mike,

If you have to use the plastic backplate there are a few things that decrease or eliminate the problem. First, use flat washers under the screws to spread the load. The plastic compresses and deforms quite a bit. Next, use thread locker in the crankcase screw threads. And, put a good bead of rtv under and around the metal washer at the manifold intake.

Mine ran great with those 'fixes'.

Ernie Misner

High temp, red RTV would probably be best.

FNQFLYER

High temp (red ) RTV or SQ 32 (also known as Hylomar) is also good.  The later was developed by Rolls Royce as a case sealent for the Dart engine compressor to turbine split.  Aslo very good on fuel lines (disolves in any known fuel that we use) and I used it on head gaskets (and rocker cover gaskets) on heaps of cars over the years.

tarcure

Thank you all for the input. Simply fantastic. I am going to order the metal back plate tomorrow. But, a few questions remain.
1. Does the carb upgrade kit help? What's different from stock?
2. Do I need a gasket with the metal plate?
3. Previous post says to replace carb screws with those from a 92 - why?

Again, thank you all.

Cougar429

My Feedback: (3)

blw, your recommendation for Loctite on any fasteners into metal components is good, but I have a couple of concerns when the casting is alloy.

First is to use a low strength as anything more aggressive is not necessary and can tend to damage the threads upon removal. On that note, unless the threads are cleaned out with a tap before reinstallation the remaining old Loctite can cause more problems.

Secondly, Loctite and plastic do not mix, so unless there is some way to prevent the two coming together during installation, the disadvantages may outweigh using it in the first place.

I have been rebuilding and resurrecting engines for a LONG time now and rarely ever find the need for thread lock. I only had the exhaust adapter come loose once on my 91, and once I shaved a wrench to provide better access when tightening it never happened again.

On that note, one thing I found with engines I grab was that in some cases it was thought Loctite a substitute for worn or partially stripped threads. This is not a good, long-term solution. In those cases I would look at moving to the next larger fastener, even if standard size. If done properly it would return the fastener to full strength.

blw

My Feedback: (3)

Some Saitos ship with a thread lock of some kind. 2 new style plastic backplates deformed quickly for me. The screws loosened in mere minutes every time. I cleaned the screws and threads and swabbed the crankcase threads with epoxy, and let it dry. That ended problems for good. I know what you mean about resorting to other ways first. I rarely use anything.

Ernie Misner

I don't think there is a gasket for the Saito backplates. You may get some oil slowly weeping out in some areas after you use lots of ARO but it doesn't hurt anything. The crankcase is vented anyway which wouldn't be good at all on a 2-stroke. Note that your 2 carb screws will have to be a different type from what is used on the plastic back plate, a metric thread like was mentioned earlier.

the pope

1.I think the carb screws. 2. yes and u can make your own if you want or use high temp silicon ( i havent done this but think it would be o.k as long as the back plate dosent hit on anything eg the conrod . Perhaps a gaskit would be best now that I think of it .) . 3. The original screws have a thread that screws into plastic instead of metal threads . Cheers the pope

the pope

Hi Ernie the 82b has a gasket on the backplate but not the a version . No gasket on the jugs . Cheers the pope

mike early

Did we agree that the Carb Upgrade Kit is for engines made more than 7 years ago?

mike early

I am getting ready to change bearings on a Saito 100Twin that has been sitting for a few years.
I have changed lots of bearings on single cylinder Saitos.

Any tips or things to look out for on my first twin surgery?

Hobbsy

My Feedback: (102)

Saito gents, I am thinking of doing a comparo between the Saito .62 and a new Saito .65, both are just past broken in. There is a difference in the recommended props, the .62s recommended prop is a 13x6 APC at 9,900 and the .65s recommended prop is an 11x7.75", no specified rpm. As to whether this is worth doing is up in the air. Maybe somone is interested how well the .62 replaces the .65. I'm gonna find out with stock exhaust and with a TurboHeader.

Quikturn

My Feedback: (12)

Hobbsy,

I would be interested in what you find out in terms of power. I have a Saito 65 on a Kyosho P-40. I like it very much but it is a heavier design. My understanding is the 62 has the same power but much lighter.

Charley

My Feedback: (2)

The .62 is more oversquare (higher bore/stroke ratio) than the .65 so you'd expect it to produce its max HP at higher RPM, hence less pitch for some applications. Doesn't look like one is a direct replacement for the other. Here's a Saito small-medium engine manual, containing all the dope: http://www.horizonhobby.com/pdf/SAIT...der_Manual.pdf

CR

Hobbsy

My Feedback: (102)

OK, I should have predicted these results, that way folks would think I am a deviner of sorts.

Fuel for both engines===WildCat 15% Premium Extra
Prop for both============= APC 13x6


Saito .65/stock muffler, rpm====9,800, rpm/TurboHeader==10,000
Saito .62/stock muffler, rpm====9,780, rpm/TurboHeader===9,990

My assumption is that Horizon got their 9,900 rpm for the .62 using 30% fuel, that seems to be their standard.

The .65 wore an Enya A-3 plug
The .62 wore a Fox Miracle

jeffie8696

Any word on parts availablity? I see several parts Ineed are backordered, maybe problems at the factory? They did have a major event in that country after all.

w8ye

My Feedback: (16)

You need to get on the band wagon with those back ordered parts.

Horizon doesn't figure their economic order quantities realistically.

You could possibly see the part remain on back order through several cycles.

For people who are on the back order list get their parts in the sequence purchased. Often the supply is depleated before all the back orders are filled.

w8ye

My Feedback: (16)

The Saito 62 is my favorite engine. I run a 13 X 6 APC prop.

I have two Golden Knights. One is still new in box. The one I use all the time was purchased in the RCU market place from a gentleman who could not keep the exhaust pipe from breaking. I put it on a plane and didn't do anything to it - not even adjust the needle valve. Low and behold, the next spring, I got trash in the needle valve and had to remove the needle to flush the system. But for the next three years, it has been trouble free,

The 62 is the largest of the small block engines that evolved in the 40, 45, 50, 56, & 62 sizes. However, the 62 has the bigger rear bearing from the 72 and the bigger cam that is in the 65 through 125 engines.

The 62 reaches a good compromise between power and fuel economy. It fits in the 40 size planes and makes them really perform.

Hobbsy

My Feedback: (102)

The .62 will idle slower than the .65, that could be attributed to the fact that the .65 still has the pre-upgrade spraybar in it.

Quikturn

My Feedback: (12)

I upgraded my 65 with the new spraybar but haven't noticed a lower idle. It only has about 1 gallon through it however.

jeffie8696

My 62 is going on the front of my Epade, Ihave a pair of skis ordered . Itook off the Magnum 52 RFS which pulled it along pretty well. So far Ihave a 45, 50 and 62 to play with. Too bad my 45 broke one of the valve adjusters yesterday and cant get the parts.

mike early

I have read through a few 100T threads on RCU posted over several years.
Am trying to reach a consensus on the Air Pump Assembly and its value.

Seems some people have had a lot of problems with the 100T and lubrication...

I have the Air Pump Assembly on this 100T. I am getting ready to order bearings was wondering if I should order a new cam cover to remove the Air Pump altogether.

W8ye, I read where you stated that the Saito Twin manual is incorrect on the cam timing of the 100T. Have they fixed it over the years?