Conference vmszoo::rc

    Try a fox .40. 
    
    md

    I would personally go with the top of the line OS or SuperTiger
    40s.  Do it right the first time, and you won't have to buy a new
    engine for your second plane.  I have had excellent luck with both
    OS and ST.  OS is easier to get parts for, but the ST starts like
    a champ every time.  (who needs electric starters!!)
    
    Cheers,
    jeff
    

I couldn't agree with Jeff more... I'd buy an O.S. or a Super Tiger
time and time again.  Frankly, I'd cough up the extra $$$ and get the
FSR, and yes, Tower's sells them.  An ABC isn't really necessary if 
you're just look'n for a sport engine, and it's been my experience that 
they [the ABC's] are a little more finicky.  Properly cared for, an O.S.
will give you years of trouble free service.  I went all summer
without dragging out my starter even once!

Good Luck,  

Brian 

    
    P.S.  Al, where the dick'ns is your plug for O.S.???? :-)

    I'll happily and eagerly endorse the previous comments expressing
    preference for O.S. engines.  As I've said several times in other
    notes, O.S. engines are worth every penny paid for them in terms
    of easy handling, power. reliability, longevity and just about any 
    other parameter one could mention.  Well treated and cared for, an 
    O.S. will deliver many, many years of trouble-free performance.
    
    I'll not dispute the favorable comments made on behalf of other
    engines and I'd be especially pleased if an American made engine
    threatened the monopoly held by foreign manufacturers but the plain
    and simple truth of the matter is that I continue to observe
    disgruntled modelers losing an entire flying session `cause they
    can't get their Fox, K&B or whatever engine to run.  Worse still
    is the fact that engine failure at the wrong time can be just as
    devastating as radio failure, frequently predicating the total loss
    of an airplane.
    
    Nope!  For my money, the extra coupla' bucks spent on an O.S are
    well worth the peace of mind their legendary reliability provides!
    
    End of plug...,adios,	Al

    Al, My FOX ran like a champ. Easy to start & tons of power. I didn't
    even have to touch the needles. Jut fuel, prime, apply juice to
    plug ,flip prop  and off I went. Also the service was just great
    when it broke & part are inexpensive compare to imports.
    
    end of my plug..
    
    

    I am partial to OS. 
    
    I now own a .40 FSR (has started all but twice by hand, I flooded
    it accidentally)
    
    Also, a .46 SF.
    
    And I just bought a YS .45, but have not started it yet.
    
    Chris

    Re: .-2, Marc,
    
    I'm truly glad to hear that you and others are having good luck
    with yer' Fox's.  I sincerely believe that competition from a domestic
    engine is needed and it is to that hope Fox is, at last, in a position
    to provide same.                   
    
    Back in my U-control days ["many" years ago], The only engines I
    ever owned were Fox's and the Fox .35 remains the standard by which
    all U-control stunt engines are judged.  Unfortunately, ol' Duke
    [Fox] went off the deep end with his R/C engines and they became
    the "joke" of the industry.  I sincerely hope he's got his s**t
    together at last but. after too many years of watching others fighting,
    cussing, even laughing at their Fox R/C engines, I'm afraid I'll
    have to be "shown" before I'll entertain running one.
    
    Maybe there's hope though, eh?  I honestly hope so.  Adios,	  Al

    re .-1: 
    
    Al, I think you should reconsider you opinion 'bout FOX engines.
    
    The RC product line in the .20 & .40 range has been totally revamped
    in  the past 2-3 years. Them are good solid pieces of machinery.
    
    md

Re: .4

< FSR, and yes, Tower's sells them.  An ABC isn't really necessary if 
< you're just look'n for a sport engine, and it's been my experience that 
< they [the ABC's] are a little more finicky.  Properly cared for, an O.S.

I have to disagree with you Brian, I think an ABC is preferable to a ringed 
motor. There is no operational difference between the two, the ABC if anything 
is easier to start because it will hold better compression.

The advantage of the ABC other than the little extra power is that it is more 
difficult to damage with a lean run as the engine will stop as it looses fit 
rather than keep running and seize. 

When running ABC engines it is better to use synthetic oil fuel rather than 
castor, that goes even for running in.

What ever engine you buy make sure you can get local spares support, during 
the life of the engine you are going to need it.

Q. Why not get the OS45, it is the same physical size and a bit more power.

John.

    
    	Has anyone read seen or heard anything about the new "Magnum"
    line of engines? From their adds they look ok. They are ABC and
    can be bought as a bushinged or baringed engine.
    
    	As far as the discussion of what is better I like a number of
    engines. What I have found is that a manufacture may have one of
    two excellent engines within his line of engines. There are many
    choises. I like OS, HB, OPS, Enya and Como/Supertiger. All of my
    engines seem to run great. I do however thing that there are merits
    to using ringed engines over ABC constructions in some applications.
    As an example in a chopper I have seen two ABC engines destroyed.
    One for running hot and the other for digesting some dirt. A chopper
    is a dirty enviornment and as such does subject an engine to more
    dust. For my money Ringed engines are ment for High temp,dirty and
    or beginners enviornments. Once you get used to these engines then
    you can go for an ABC. If your looking for brut performance there
    is only one choise. ABC.
    
    						Tom

    
    I have been using a ENYA SS40, buget priced engine, for about a
    year with no problems. The engine has suffered 3 quite nasty crashes,
    not its fault, and just keeps going.
    
    I considered the FSR ABC and all that, and decided that I would
    start with cheep simple engine until I got some experience. I have
    seen OS40FP work just as well as my ENYA but cannot comment on the
    crash resistance as the owner is a better pilot than I am.
    
    Both are very simple to run, electric starter wot's one of them,
    and for a trainer I wonder what benefit you get for the extra
    technology and subsequent cost.
    
    					Gook Luck
    
    					Mel Proudfoot

    John,
    	I agree with .22 except about prop weight having any positive
    effect on pre-ignition.  Prop loading surely does, but this is mostly
    pitch and diameter.  The faster the engine turns (and the less it's
    loaded) the less time there is for early ignition.  Loading it down
    with a big prop accentuates the problem by slowing down the engine
    and increasing the combustion pressures and temperatures.  
    	I do have a question since I have never run my 4-stroke yet.
    Several people have told me that they run their engines with extra
    head gaskets to reduce detonation.  The OS manual says nothing about
    head gaskets, but I know that Enya ships a gasket with some of their
    4-strokes.  Most people I know that have an Enya 4-stroke run with
    this in place.  Should I try and find a gasket that fits my OS1.2?
    
    Charlie
    

    re .23
    Charlie,
    For what it's worth, I have been running an OS FS120 since May 1986
    without ever having any detonation or kickback problems. The fuel
    is my own mix (sorry John Chadd!) of 5% castor, 5% glo-glyde, using
    a plastic 16 x 6 (relax, I changed to wood recently for safety
    reasons).
    My motor is the early model which I believe has a lower compression
    ratio than the later MkII and the Enya. Hence, an extra gasket does
    not seem warranted.
    
   After I spent the running in period learning about four strokes,
    I have not had any trouble starting or running this motor. If it
    doesn't start in less than 20 seconds, I'm doing something wrong,
    usually not enough choking.
    I'm very pleased, good luck with yours.
    
    Tony
    

    Tony,
    	Thanks for the good luck wish.  Are you running no nitro in
    your fuel?  Do you use a tach to set it up?  I should have mine
    running by early July.  I have my Sportster 90 ready for finish
    sanding and covering, but I am going on vacation next week, so i'll
    be getting ready this week and gone next week.  
    
    Charlie
    

    Charlie,
    I did run in the FS120 with 5% nitro as that was the only four stroke
    fuel I could get at the time. Since then (about four litres, I think),
    I have not used nitro at all. In fact, it is so expensive in Australia,
    that I use just 5% synthetic, 5% castor for both two and four strokes.
    
    I have never used a tacho, but may get serious one of these days.
    Most of my flying is in slow sport biplanes, and I seem to be able
    to tune well enough by ear.
    
    Regards
    Tony
    
  

Charlie,

I am not saying the heavy prop is a positive effect, in fact it is just the
opposite. Pre-ignition (detonation) is detrimental to the life of an engine, it
exerts excessive and unnecessary strain on the engine components. 

You are absolutely correct about extra engine load increasing the temperature,
however the combustion pressure is a function of the RPM or more specifically
the the duration of the combustion stroke, the amount of mixture burned, and to
be absolutely correct the initial temperature of that mixture and the air
density. 

Extra gaskets will increase the combustion chamber volume and improve needle 
margin. It will most probably eliminate the detonation. It is well worth a 
try.

As for Tony mixing his own fuel..... shame on you. The mixture of 5% Castor 5% 
Glo Glyde is a good one, I would personally cut down on the castor or even 
eliminate it for the benefit of a cleaner engine and model.

John

    I have read and seen lots about props coming off 4-strokes, and
    solutions like pinning the shaft.
    
    What about a lock nut of some type? It would seem that a lock nut
    would allow the prop to loosen and spin but without coming off.
    Am I missing something?
    
    Bill

Bill its a good thought unfortunately its not workable. It has been tried and 
the problems have been found to be:-

	o If you use Nylock Nuts, the nuts with nylon inserts; it is next to 
	  impossible to tighten them. There is no way to stop the crank shaft 
	  rotating while you tighten the nut.

	o If you use a second nut the shaft tends to be too short. It also 
	  prevents you from using screw on spinners.

I still believe the best solution is to stop the kick back and reduce if not 
eliminate the occurrence of throwing props.

Sorry 

John.

    I have no 4-stroke experience myself, but in following the
    safety column in the AMA magazine for a few years, there
    have been several discussions about it.
    
    Pinning the prop is considered dangerous because it requires
    drilling a hole in the prop hub which will weaken it. Since
    the motor already has a tendency to kick, it might just break
    the prop instead of kicking it off.
    
    As far as lock nuts, just take out the glow plug and jam a screwdriver
    down the hole. This will lock the piston and keep the crank from
    turning. :�)  -- (supposed to be a tongue-in-cheek-sideways, whoever
                      started those stupid little pictures anyway?)
    
    
    Dave

    The new OS 1.2 Surpass comes with a second lock nut for the prop
    that goes on after the prop nut.  It is supposed to allow the prop
    nut to loosen but not come off if the engine tries to spit the prop.
    I haven't run mine yet, so I have no experience with how effective
    this will be.  It does make putting a spinner on more difficult.
    
    Charlie
    

    I've had some experience with four strokes both my own (O.S. FS-40
    and FS-48 Surpass) as well as some others in the club.  Prop throwing
    is caused primarily by engine detonation this usually happens when
    the engine is run too lean.  Solution, always use a tach during
    engine break-in don't try to tune by ear.  In fact you can hear
    the detonation occuring and it had me fooled that I was getting
    additional rpms.  Sacrifice a little performance by running the
    engine slightly rich, if the plane and engine are well matched you
    won't realize the difference anyway.
    
    Assuming the worst keep in mind safety - always tweak the needle
    valve from behind the engine not to the side, stay out of the prop
    arc.  If working alone, start the engine at idle then move behind
    the plane and don't point the spinner at anyone!  Also wear eye
    protection, I've been hit by a flying prop nut and I wouldn't want
    to take it in the eye.
    
    Scott

    Does anybody know if Super Tiger makes a marine type cooling head
    for their S3000 engine??  A friend is in need of more cooling
    capability in his Eindecker.
    
    Thanks,
    jeff
    

    Jeff,
    
    I don't think so but I sure wouldn't put any money on it.  All I
    know is I've never seen a thin on marine heads or other accessories
    for the big 2000/2500/3000 Super Tigre engines.    

      |
      | |      00	 Adios,      Al
    |_|_|      ( >o
      |    Z__(O_\_	(The Desert Rat)

    al, would a ch ignition help temp much on the st3000.
    
    davis diesel makes a head for these engines tho i wont
    recomend that.

Jeff,

I would not recommend using a liquid cooling system for the ST3000 engine for 
the following reasons.

	1. Extra weight of the head and the coolant.
	2. Extra complexity of construction. (radiator, header tank and pump)
	3. complexity of operation. (putting coolant in at the start of the day 
	   and removing it at the end of the day)

The engine should with correct air ducting be adequately cooled. Your friend 
should also remember it is as important to ensure hot air can escape from the 
cowl as well as cold air getting in to the cowl.

John

    Kevin,
    
    The only CH spark ignition set-up I ever saw was on Chuck's ST-2500
    in his Platt P-51.  I can't honestly say whether it affected
    temperature or not as this ship never had a heating problem to start
    with so we paid no temperature to this parameter.  It _did_ seem
    to have a very positive effect on performance, starting and idling
    in particular...there may've been a slight increase in top rpm but
    I'm not sure of that anymore - 's been a little while back.
    
    Are you having a temperature/heating problem with the Jug?  That'd
    really surprise me what with the engine essentially hanging out
    in the breeze as it does.  One thing; you should baffle the front
    of the cowl such that the air is only allowed to pass over the cylinder
    head and adequate air exit area should be provided at the rear of 
    the cowl.  This baffle makes a splendid base upon which to mount
    yer' dummy engine cylinders so it's functional to boot!  

      |
      | |      00	 Adios,      Al
    |_|_|      ( >o
      |    Z__(O_\_	(The Desert Rat)

    Wait a minute,
    
    You've got a (note correct spelling, Kay) "WEBRA" Bully in the Jug.
    What are we talking about regarding the ST-3000?  In _any_ event,
    I'd avoid the Davis diesel conversion...I've yet to see one that
    performs up to glo-standards, let alone exceeding said performance
    as is claimed.  Fact is, we saw a guy lose a very nice P-51 in Coloado
    Springs due to the lack-luster performance of his diesel-converted
    ST-75...Hell! the glo .75'd a pulled the wings off the bird but
    it struggled into the air, snapped and crashed due to being
    underpowered.    

      |
      | |      00	 Adios,      Al
    |_|_|      ( >o
      |    Z__(O_\_	(The Desert Rat)

    yes, al, i'm using a bully in the baker jug.  i was just trying
    to help out jeffs friend of a few replies ago.  i had remembered
    your raving of the c+h ignition from a while ago...
    
    yeah, the davis diesel heads give you "more power" in comparison
    of a comparably displaced (old technology too probably) 4-stroke
    maybe.
    they're definately not up to 2-stroke power capability.  i found that
    out for myself.
           
    as another suggestion for jeff, i found out with my bully that is
    needs lots of fuel at high speed.  the inside diameter of all fuel
    line must be quite fat.  dont forget the fuel line/tubing/klunk
    in the tank!  if fuel line is too restrictive, engine runs lean
    at high speed regardless of needle valve setting.  this might be
    the real cause of overheating.
    
    the documentation that came with the bully even stated that using
    normally lubricated fuel can cause lean runs due to extra viscosity.
    they recomend "thinning" regular glow fuel with straight methanol
    (if i remember correctly) to reduce oil content.  big engines turn
    fewer rpm's and need less oil in fuel.  what fuel do they recomend
    for that engine.  i'm using special "bully/tartan" fuel from circus.
    
    for my bully i'm gonna go up to a bigger fuel diameter yet.
    
    hope this helps.
    kevin

    I'm not sure where to put this question, but this seemed like a good
    place.
    
    I'm considering one of two engines for the CG Sky Tiger: either an 
    OS .46 SF, or an OS .50 FSR.  The power specs for these two engines are
    very close, being 1.43 bhp and 1.45 bhp respectively, but the price
    difference doesn't seem to justify the .50 over the .46.  Can someone
    help me understand why OS markets two such similar engines, and what
    decision criteria go into choosing one over the other?
    
    Thanks,
    Joe  

    Joe, 
    
    The FSR series of O.S. engines were/are the top of the line with
    schneurle porting, double ball-bearing suspended crank, top-of-the-
    line carb, etc. etc.  I don't know exactly what the differences are but
    the SF and FP series are aimed more at the sport flyer market, the FP
    having busing, rather than ball-bearing supported cranks.  Someone like
    a Tom T. or a John Chadd may be able to be a little more specific for
    ya'.
    
						 __
				|      |        / |\	   	       
      	         \|/		|______|__(o/--/  | \	   	       
      | |        00	       <|  ~~~  ____ 04 ---- | --------------------
    |_|_|        (O>o		|\)____/___|\_____|_/	   Adios amigos, Al
      |     \__(O_\_	        |	  |___/	 o	   (The Desert Rat)

    The SF series is the better, smoother and more powerful replacement for
    the FSR line. They contain all of the old FSR goodies, plus
    enhancements. I own both a .40 and .46 SF. They are quiet, powerful,
    and very smooth running.
    
    
    							Dave
    

    I agree with Dave.  The FS series is at least as good as the FSR
    series.  The 46SF is much newer than the 50FSR.  THe difference in 
    displacement between a 46 and a 50 is not much!  The SF's have baffled
    mufflers which really cut down the noise.  I'd go with the 46.
    
    Charlie
    

    
    I'd like to "throw" in my 2 pennies worth.
    
    First, I believe the O.S. FSR is better (and more powerful) then
    the SF.  Exactly what makes it better is beyond my knowledge.  (
    I  wish 'they' had taught me things like this in college but NO
    it was all the "important things."  Anyway, I have used both engines
    on a 40 size SIG.  I had a 46SF and 50FSR and the difference was
    unmistakable.  Speed and vertical performance was much better on
    the FSR.  
    
    Of interest:  I just recovered from a swamp my 40SF.  It was in
    an Airtronics Jetfire 40 that went down due to transmitter failure.
    The plane lost elevator and promptly proceeded to follow the law
    of gravity.  It landed in a swamp that was created by a lake
    being over its limit.  (The lake has since gone done and water
    has receded.)  Upon recovery the engine was found to be full of
    water, dirt everywhere and overall in bad shape.  Nothing was broken
    other then two of the cooling fins on the cylinder head.
    
    After cleaning with WD40, kersosene and a wire brush I put the
    engine in a home-made "teststand" and started it up.  It took
    a few tries but within tens mins. of fooling around with it the
    thing started.  That's a good engine!!!
    
    I plan on putting it in a recently purchased, and new on the market,
    SIG Midstar 40.
    
    In my opinion nothing comes close, for the money, to an O.S.
    
    Rich

Quick question:


When I got my Magnum .45 Pro (in Utah last summer),
they also had the Royal .45 for the same price.

I looked at both and they looked to be exactly the
same engine in 99% of all respects except of course
the name on the side (that difference not included
in the 99%).  Even the accessory bag was the same!

I chose the magnum because the booklet was better.

Anyway, the question:
Are these really the same engine?  Made in the same
factory in Tawain?  (Both have the same stamp Made
in tawain on them).

Chad