NJD

My Feedback: (14)

Does anyone know anything about this engine?
I can't wait to try one.

http://www.os-engines.co.jp/english/...70ultimate.htm

1.2 HP @ 11,000 RPM
455 G Weight - lighter than Saito 72!

NJD

Chuckr53-RCU

My Feedback: (40)

I sent an email to the OS Engines importer Hobbico asking when they would begin importing the OS FS-70 Ultimate, and here's the reply:

Thank you for your recent e-mail.

Unfortunately we do not have access to that information. However, I
have forwarded your suggestion to the appropriate product managers for
future consideration. Thank you for your time and interest! Please feel
free to offer any additional product suggestions directly to the
product managers by using the "product suggestion" form on our web site.

Again, thank you for your time and interest.

DID YOU KNOW that our web pages now all contain FAQs? (Frequently asked
questions) Please drop by and take a look! We hope you'll find the
information helpful and valuable to you.

Sincerely,
John G.
Product Support Technician

w8ye

My Feedback: (16)

It appears to have a pump and a regulator type carb?

Jim

Chuckr53-RCU

My Feedback: (40)

What's surprising to me is that it has the pump and it's power and weight are very close to that of the unpumped Saito 72.

The pdf file refers to a "slide valve design" carburetor..."a first for a 4 stroke engine". Do you know what a slide valve design is?

ShempHoward

My Feedback: (3)

If you have read any of the 3 magazine tests run last year on the Saito 72 when it first came out you would have seen that all three testers made mention that the the 72 ran 200-400 RPMs slower than the 70 Supass/70 Surpass II on a variety of props. I suspect if you used 30% Nitro on the Saito then it would catch up and perhaps overtake the 70 Surpass running on 15%.
Nitro. Higher Nitro on the Surpass made no difference in RPM gain. The new 70 Ultimate might even be comparable to a YS 63? Apparently we can look forward to a new line up of "Ultimate" 4 strokes from OS. The long overdue 140 would be nice.

Spike373

My Feedback: (1)

Has anyone seen these available yet? Date? ---Mike

Sprink

Sent an email to OS when I first read this email. No reply as yet.

Nothing on Tower Hobbies yet either. They tend to be among the first in my experiance. Probably years before it gets to the UK where I am.

The article above says it is the first of a new range. Wonder what will be second. If they make a lightweigh 120, that will be a killer.

Shortman

My Feedback: (21)

That will be a sweet motor! I had the original OS 70 Surpass right before they discontinued them and made the II series. Great running motor and very reliable and user friendly.

Flypaper 2

Slide valve carb has a plate that slides across the venturi. Mikuni has been making them for a number of years for high performance snow machines. The square piece sticking out encloses the slide.

coolbob140

they use slide carbs a lot in the model cars..
they provide quicker throttle response than a rotary carb

RobertC

My Feedback: (157)

Bax ("local" Hobby Services rep) posted an estimated date and price in another thread... check here:

http://www.rcuniverse.com/showthread...ht=70+ultimate]

ShempHoward

My Feedback: (3)

If it has pump on it you can be certain it won't be cheap. I'm guessing a street price of $270-290. If thats the case you might as well get a YS 63 or spend a little more and get the YS 110.

Spike373

My Feedback: (1)

Those prices put it out of my league! I will put a Hacker in it first. The ys is looking real good. -----Mike

kobago

Hi all
I think that OS70ultimate is really good.
This engine doesn't have a super charger, and it is simple structure.
Therefore, it is sturdy.
It has the power which is the same as YS63, and weight is a little light, and a price is a little low, too.

PatternFlyer

My Feedback: (182)

Kobago,

Any news on YS FZ63-S? Linerless.

YS says it is lighter than current 63FZ.

If the price of 70 Ultimate is right around the current price of YS 63 from Central hobbies, I will probably get one, but after hearing actual testing result.

kobago

Hi guy.
I read that news on a home page of YS, too.
It is said that it is lighter by 10g than the FZ63 engine old type.
The purchase price of the old YS FZ63 engine is 240 dollars in Japan. (1 dollar=120 en)
Then, OS70ultimate is 233 dollars.

RaceCity

What was wrong with the old .70? I have collected a total of three of them since the surpass series first came out in the 80's and they ALL run as new. (Castor based fuel BTW)

Never paled next to a Saito .72 either. Around 9.7 - 10K at WFO with a 13-7 APC, 10% fuel and a nice rich needle setting.

I think the new "ultimate" .70 is nice, but it's a lot of eye candy too.

My $.02

PatternFlyer

My Feedback: (182)

RaceCity,

Nothing wrong with Current OS 70.
It is a great engine.

Here is what I think.

OS probably is trying to compete with YS.
When OS 52 showed up, YS produced 53FZ which had considerable more power, but with more weight.

I used YS 53FZ in place of OS 52 because of power output.
Many people in Japan also used 53FZ in place of OS 52.
Japanese fly lots of small size pattern planes compared to US.

When 63FZ came out with more power that could outrun the OS 70, many people also went to YS 63FZ.

Lots of people used YS 63 in place of 70.
Since displacement is larger than 63, I believe OS decided to lower weight for competition purpose to compete with YS 63FZ.

With current 1 year warranty and many people having trouble correctly running the YS engines, I think 70 Ultimate will be a hit with 2 year warranty, better quality control, and equivalent power output.

I run YS 4-stroke only in my Pattern planes, including the 63 in EZ Topline, BeatOn, HideAway etc. All these small EZ planes were built around OS 52.

Time will tell the outcome.

RaceCity

'Mornin PF....

I understand that there's nothing wrong with the "old" .70...like I said, I've owned them for 15 years.

Good points on WHY the new edition is forthcoming as well.

Still....we both know why 99% of the people in this country will buy them....and it's NOT for competition.

"Mine's bigger than yours!" Comes to mind instantly. <GGG>

Oh well...I'll stick with the old ones.

Regards,

Race

ShempHoward

My Feedback: (3)

One problem with your theory is that the OS 52 was around long before the YS 53 ever showed up.

Steve Campbell2

>

That's what he said; read it again.

And I agree that this new 70 Surpass is, in all probability, in response to the YS 63.

I just wonder how big it (the new 70) is. The YS 63 is no larger than a 46 FX two stroke. And it is a monster, power-wise, with the appropriate fuel and prop.

Too bad they are so temperamental...

Steve

futaba1024

Hi
I believe the OS70 ultimate is based on the 52 size case, however at 1.2hp it is still way off the pace of a YS63 which makes in the region of 1.5hp.

RaceCity

...and my POS ASP .61 makes 2.1hp. Yeah....right.

I'm not sold on HP figures in model engines. "at what rpm? with what prop?"

Am I the only one that gets the feeling that these HP figures are arrived at by mad scientists on some other planet?

If a motor can "do the job".....that's the spec I'm interested in.

Happy Independence Day All!!!!

'Race

futaba1024

Racecity
Using thrustcalc HP, it would appear that the manufactures hp figures are generally achievable on 4stroke motors where as the numbers quoted for 2strokes using real world prop set ups are not. A few examples:-
4strokes
Saito56 Quoted .95hp actual 1.08hp 12x6 @10700
YS63 " 1.5hp " 1.41hp 13x4 @12000
OS52 " .9 hp " .91 12x6 @10100
2strokes
OS46fx " 1.6hp " 1.05 10x7 @12800
OS91fx " 2.8 " 2.25 14x6 @11100
irv 53 " 1.8 " 1.38 12.25X3.75 @13200

Cheers.

RaceCity

You're correct...I meant that comment in a "general sense".

4C's DO achieve their power in a range where the modeler can actually "access" it....unlike many 2C engines who's peak HP is developed at an RPM that would require a painfully small (and equally worthless) prop to achieve.

My original point was....the OS .70 'Ultimate" is cool...but it remains "eye candy" IMO. It's a philosophical issue with me....

Spend all that extra money for some blue anodize and a couple tweaks? Not me.

Save an ounce of weight? I build my own stuff...I can save a POUND of weight for free...Use the regular .70 and outperform you in every respect.

So....

PS: Can't wait to visit UK again....excellent!