Black horse Stuka engine

[Ian Mat]

I managed to nab a bit of a bargain on ebay last night and am the proud owner of a Black Horse Stuka, which looks immaculate. All it needs is an engine and I have a choice of 2 to put in it... First choice is a new ASP 91 four stroke, which the manual reckons is the minimum size. The second choice is a second hand YS 140L four stroke, which is bigger than the maximum recommended 120, but will easily fit under the cowl and weighs about the same as the ASP 91.

What do you experts reckon?

[Ian Mat]

Should have probably mentioned, it's the 1820mm wingspan version.

[Ian Mat]

Should have probably mentioned, it's the 1920mm wingspan version.

Edited By Ian Mathews on 10/02/2015 21:06:18

[..]

I think it will struggle with a 91 Ian.

[Phil Francis]

Seen three of these at our flying site, it won't fly with a 91 fs.

[Ian Mat]

Guess it's looking like the 140 then... Thanks guys

[Jon H]

the 91 would give a scale performance but nothing more. the 140 might pull the wings off

[Ian Mat]

Can there be that much difference between a 140 and a 120?

[YakMad]

There is a big difference in power between a correctly tuned YS running on the recommened fuel and a 120, I would suggest you bench run the YS before you decide to fit it in the model as they can be difficult to tune and it will give you some idea of the power from the engine, as far as I can remember I think the YS can turn up to a 17x8 or 17x10 prop, a 120 will only turn about a 15x6 to 15x8.

[Bob Cotsford]

those props put the YS in other manufacturers 180 category!

[Ian Mat]

Thanks guys, I'm starting to realise that the YS was a mistake. I had heard that they were good engines and I got this one quite cheaply. I think I might have to sell it on and buy a SC/ASP 120 which is what most people and the manufacturers are recommending.

It will be a while before I'm flying this model, I need way more practice on the foamy warbirds and my WOT 4, before I would even consider flying the Stuka.

[Jon H]

YS engines are:

Good quality
VERY powerful
very reliable when set correctly.

They are also:

A faff to set up if you don't know how
Very fussy on fuel/props and sensitive to dirt/debris.
If crossed they will spit their prop in your face and will kick hard enough to shatter cast aluminium spinners.
prone to fuel tank leaks as they run a highly pressurised fuel system.

A friend of mine has bought a number of them as you have and its taken him a good year to really get to grips with their operation. They run well now but are always a faff and are not flick and forget engines that just work. If you don't mind learning the ropes and chewing up 20% nitro fuel then go for it as they are fantastically powerful, if you want an easy life then I personally would suggest something else. I could be wrong so please correct me, but you seem to be not that experienced with engines and as such I would not recommend it for you.

The SC/ASP engines are cheap and work just fine for what they are. You could also consider OS 110-120, Saito 115 or 125 or Laser 100,120 or 150.

 

Regarding the Stuka, the instructions from Blackhorse/ripmax make mention of the fact that it tipstalls. For them to write this in their sales blurb basically means its got a serious bite if mistreated. I would strongly suggest you become very proficient on another heavy engine powered warbird before you even attempt to fly the stuka. It will be a world apart from anything foamy as (by comparison) it will feel like a flying brick with much higher landing speeds.

Edited By Jon Harper on 11/02/2015 09:39:32

Edited By Jon Harper on 11/02/2015 09:41:33

[Ian Mat]

Jon, you are correct, I'm not that experienced, not with large warbirds, or 4 stroke engines! I have had plenty of hours mucking around with cheap 2 strokes about 20 years ago, but they were in helis.

I have read similar reports about the tip stall on the Stuka, due to the taper of the wings, although the dihedral of the wings makes it fairly stable. Anyhow, I'm nowhere near the level required to fly it yet, I have stalled my 1200mm P51 a couple of times (the second time fatally), so as you say, I definitely need a lot more stick time. That Stuka is a big model and could do some real harm in the wrong hands (i.e. mine!).

I have decided to go for an ASP 120, Hobbyking are selling them for £135 and I will bench run it lots, to run it in and get used to the tuning etc. SO I will have to sell on the YS and write that purchase off as a rash mistake!

[..]

That's sensible Ian , get yourself a cheap powered low wing plane before you fly the Stuka . Something with flaps would be good. I've seen 2 Stukas tip stall so you need to refine your slow speed flying.

[Ian Mat]

Justin,

I'm currently flying a Wot 4 electric and starting to enjoy chucking it around. I also enjoy attempting to fly an electric P51 with retracts and flaps. My IC Wot 4 should maiden this weekend, so when I can fly all of those properly I might consider the Stuka... maybe!

Edited By Ian Mathews on 11/02/2015 11:21:48

[..]

Good luck.

[Jon H]

For £135 you cant go wrong with the ASP. I do however suggest you adopt a slightly different running in procedure than the one normally recommended. As it is quite convoluted to explain it might be best to do over PM, unless there is other interest here.

Also, a prolonged bench run will not achieve much and you could put the engine in another model to as to gain experience with bigger and heavier models. You will also have a tried and trusted engine to put in the stuka at the end of it all as well as greater experience.

Edited By Jon Harper on 11/02/2015 13:30:59

[Ian Mat]

Jon, I would appreciate any words of wisdom! I have never even run a 4 stroke and would like to start in the best possible way!

[Jon H]

No problem. I fly many warbirds of 70-80 inches and very much enjoy them. Anyone who tells you a scale model is hard to fly is talking rubbish. They are not hard, they just require different skills in certain areas and are less forgiving when outside of their performance envelope.

I know for a fact (because I tested it and because of videos I have seen) that my 80'' La7 will tipstall very violently if pushed too far, but as long as you don't go too far it behaves impeccably and will in fact land very slowly even though its almost 20lbs.

All it takes is a few minutes getting to know the limits of the model, and then slowly over many flights you work up to those limits so that you end up flying the model up to 90% of its capability all the time with a 10% margin for safety.

As for the engine run in procedure. I will write that out when I have more time.

[Engine Doctor]

Posted by Ian Mathews on 10/02/2015 22:32:09:

Can there be that much difference between a 140 and a 120?

Oh yes ! A YS 140 is much more powerful than any of the other make 120's on the market. But you do have a throttle . One thing to watch out for if you fit the YS 140 is the ground clearance neded for the prop . I fitted one in a Flair leo and then realised that I could not fit a prop bigger than 14 inch dia. I ended up with a 14 x 14 apc which it spun easily .. The YS is a great engine but prop choice is critical to stop it over revving if there is limited ground clearance.

Oh yes and as said in other post they are very much not fit and forget and  like 20% nitro. 

Edited By Engine Doctor on 12/02/2015 13:42:51

[Ian Mat]

The YS was a bargain by all accounts, because it had no exhaust system. A quick call to Just Engines solved that problem, so now it's complete. I think I will give it a good oiling, wrap it up and save it for later.

I have purchased an ASP 120 FS for the Stuka, which is the recommended engine and makes sense to install, but even then I won't be flying it until the end of this summer, at the earliest! I intend to bench run the ASP to ensure that it is completely reliable and help me to learn the nuances of 4 strokes.

Thanks for all the great advice though guys, this forum is a wealth of information!