tande

My Feedback: (48)

Well....Put my new YS70 in my old "Venus 40" & got a couple dozen flights in today....Guys, this one is a "Keeper"...Starts/idles/transitions perfect & then "Hauls" at full/throttle...Talk about "User/Friendly" I don't know how it could be any better....I sure hope the new 115 is as good...FWIW

petec

My Feedback: (58)

I'm jealous. I called Richard at YS the other day about getting a 70 and he told me the first shipment is already sold out and the next one is on it's way from Japan.

nonstoprc

My Feedback: (90)

what prop are you using? Any RPM numbers?

tande

My Feedback: (48)

Started with a 12x7 APC & now a 12x8....I will get RPM no's for ya....(I was having to much fun to take time for a "Read" )

tande

My Feedback: (48)

petec...I think you'll agree it is worth the wait [:@]

tande

My Feedback: (48)

Hey Guys....Just a couple RPM #'s for ya (& it's there "Right/Now" )...APC 12x8=11400/11500...13x7=11300/11400...These are "Manual" recomended sizes...Details...
Fromeco TNC tach
Performance Specialties muffler
25% nitro
75*F./80% humidity, Michigan weather [&o] & now today 7/14/10....APC 13x8=10800....85*F

airraptor

My Feedback: (66)

those numbers seem to be stronger than OS 91FS. what does it weight?

tande

My Feedback: (48)

From "Central Hobbies" site....488g w/muffler....

ChrisAttebery

My Feedback: (15)

That's stronger than the Saito 82 too. I was getting 10500 with a MAS 14x6 S2 on 30%.

faulknej

My Feedback: (9)

Hey Pete, Hobbybarn shows them in stock for $309.

ferio

My Feedback: (8)

Those are impressive RPMs on the new YS70. I think you got a winner here.

Guillermito

On the web I found two photos of the YS 70FZS, which is what is sold?

tande

My Feedback: (48)

The one with the reg. attached to the carb...

akaram

Hi,

I got a YS-FZ70s for my VQ-MIG3. Been in the hobby for more than 20 years now and this is my 1st 4-stroke engine.
I am amazed at the power and torque it produces, with an APC 12x8 and WildCat Heli 30% fuel I am getting 11500 - 11700.

What I didnt like about the engine is the need to retune it every weekend and the amount of vibration it produces.
With my 2-stroke OS engines, after finishing break in, I find the sweet spot and never touch the needle again for the lifetime of the model, as with this YS I have had more than 30 flights to date and every weekend, after having found an excellent setting for the low and high needles the previous week, I run the engine to find it lean or rich and again have to set the needles, is this normal with 4-stroke engines and YS engines in particular ? moreover, turning the high needle does not produce immediate and gradual rpm change for small turns like 3 or 4 clicks so tuning it is somewhat sluggish.

The other issue is vibration, on the 1st day after 5 flights I came home, had a look at the fuel tank and found it badly scoured by vibration at every place where it touches the plywood formers ! I install my tanks in all my 2-stroke models the same way and never had any problems with tanks being scoured even after 300 flights !!!
I have owned his model for only 2 months now and have already disassembled the cowling 4 times to date to find fuel tubing badly scoured almost pierced at places where it comes in contact with anything !!!

The great power I am getting is offset by those high maintennce requirements.

Please let me know if this is normal especially the tuning thing

tande

My Feedback: (48)

Well, FWIW, first/off...Welcome to the "YS World"!....Assuming your prop/spinner are balanced correctly, the vibration could be normal, (you did say this is your first 4/stroke engine), "Most" of us use a vibration dampening engine mount of some type...I have a dozen YS's & ALL are mounted on "Hyde/Soft/Mounts"...As for "Chasing the tune" I have two of the 70's & don't find that to be the case...Only when changing fuel blends (and that includes "Brands") or significant weather changes...Some simple questions, your fuel tank is holding pressure?...You are using a YS or OS 4/stroke glow/plug?...Oh yes, & thanks for posting about your YS 70...
Ed

akaram

THanks for your reply Tande, My prop and spinner are perfect so the vibration is normal I guess, I am using the normal engine mount, will consider changing it to a vibration dampning mount, will check now what central hobbies have.
As for "chasing the tune", the tank holds pressure perfectly, sometimes I forget to release the pressure immediately after the flight and after 1 hour I find the tank still pressurized. As for the glow lug it is an OS type F

tande

My Feedback: (48)

Sounds normal, especially with high nitro % (broadens the tuning range)....From this end, it sounds like you are doing things right...Hopefully a little more run/time will settle things down...These little guys are "Beasts" (for their size) and maybe somewhat fussy...But well worth it, IMHO, for their performance..
Ed

akaram

Yes definitely worth it ! As I said the power is amazing ! I and 5 of my friends have got bitten by the WWII bug thus we are all flying 50 sized warbirds, I have the YS, the rest fly OS, chinese ASP and Saito four strokes. We fly in formation most of the time, when I hit full throttle the rest are history, I have almost double the speed and unlimited vertical whereas the rest almost stall after 1 vertical roll
But now I am trying to figure out whether I should really go and buy a hyde antivibration mount or I can live with the vibration as it is ! It is $50 at Central Hobbies for the 70, not cheap at all for a mount !!!

tande

My Feedback: (48)

Yup!...But they do last forever (well, almost) and can be moved from one airframe to another....In all my years of using them, I've yet had to replace one...Also, I've never heard a SERIOUS argument against reducing airframe vibration! [sm=wink_smile.gif]