Simon Jones

Bill

Sounds like your on the same wave length, soo many toys, so little time (not to mention Domestic Credit. Light and rear engined is far from the sterotype.

Like you say back to RC. I take it from what you said about castor it's any form of pure castor oil. I guess it doesn't need to be filtered if from the pharmacy. Is there anything that we ned to look out for lie purity ratings or the like.

I got some 5% wildcat for my 160 today and I inted to add some castor as per your suggestion.

sj.

rajul

My Feedback: (58)

I see some folks claiming no gumming and carbon build-up in using fuel with castor/synth mix, while some claim to have that problem. What gives ?

William Robison

My Feedback: (3)

Simon:

What I'd like to have as a toy is a 750cc Moretti, with the twin cam engine, and the two Weber 35 DCO carbs. Wild machine, I got to play with one for a short time some 40 years ago.

Almost any source of castor oil is OK, just be sure it is pure. Some laxative castors will have other things added, so if you go to the chemist's shop be careful. I've never seen any that needed to be filtered, beyong the fuel filter in the airplane. You do have a filter there, don'tyou?

Bill.

William Robison

My Feedback: (3)

Rajul:

With the castor at 18% to 22% you will get some residue, but keeping the castor percentage down around 3% tp 5% and the balance synthetic you still have the protection, and I've never had a problem with residue or varnish.

Bill.

rajul

My Feedback: (58)

Bill, how often do you clean up the valves, if not at all ?

JCOKEEFE

My Feedback: (2)

[8D]I have both Saito and OS(4S) engines. In my opinion, both are on a par with
each other. It's a matter of personal choice. Both brands are of high quality and will
last a long time, if not abused. My only disappointment with OS 4S engines is that
they do not, for some reason, manufacture a single cylinder 4S larger than a 1.20.

William Robison

My Feedback: (3)

Rajul:

Generally I don't pull the engine down unless something else has let go. By using a hardwood stick you can go in through the ports and scrape the stems if there's any build up, the valve can be turned with a pair of needle nosed pliers on the spring cap, allowing you to get it scraped all around.

I had a problem with a four year old FA-80 that turned out to be a broken valve spring, by the time I found that I had the engine stripped. I'm working up a posting for Saito overhaul, using that engine as the subject. I'm replacing a lot of parts I would normally have reused, reasons will be explained in the posting.

But just for a valve spring, as I stated earlier, I'd just hold the valve up and change the spring without taking anything off except the rocker arm.

And how often? Check them once a year, part of my annual on all the 4c powered planes.

Bill.

rajul

My Feedback: (58)

I'm certainly looking forward to your article !

Razor-RCU

My Feedback: (50)

IMHO:

1. YS
2. Saito
3. OS

William Robison

My Feedback: (3)

Rajul:

Here are two pictures from it, the first is the broken valve spring that started the whole chain of events, the second shows the damage to the camshaft from the valve float.

Bill.

rajul

My Feedback: (58)

Hi Bill, the camshaft and gear look oxidised ?

William Robison

My Feedback: (3)

Rajul:

Normal appearance from new - case hardened.

Did you notice the depression hammered into the cam?

Bill.

Sprink

Simon Jones,

Thanks for the info on Wildcat, I have sent an email to Liskaerd Models, I'll see what they say.

Simon Jones

Bill I'm affraid I have to admit to ignorance on the 750cc toy you mentioned, possibly a wrong side of the pond thing (and maybe the fact that I wasn't born when you last played with one). It is great to hear that the american stero type of big cubes with zero handling is not being susbscribed to by everyone over there. I'm affraid that my experience of enginr tinkering (so far) has been limited, with my favourites being the VW air cooled and the Rover V8 (which I think you might know as a Buick 215). I'd love to grt back to the Rover V8 and start playing with NOS one day, especially as I like them in Land Rovers.

I picked up some pure virgin castor oil today and I'll be adding 3oz to my gallon od 5% wildcat as the posts seem to suggest as the best mix. I should have a carb back tomorrow or Thursday so I'll let you know how it goes on my Idle post.

Sprink, your welcome. I hope Gareth and Tracy look after you.

sj.

rc-sport

My Feedback: (12)

I have 5 Saito's , yesterday I added my 6th (FA-100) and I haven't had a bit of problems. My first Saito was and old and beaten 80 that I got dirt cheap, I sent it in for a once over and its been a strong performer for 2 years now. I picked up the 100 yestreday, not sure if I like the new muffler though. A couple of guys at the field have YS engines and they spent alot of time fiddle farting with them. I start my engine, set the mix and fly. I'll stick with Saito thank you.

William Robison

My Feedback: (3)

SJ:

I go back a long way with Rover, my graduation present in 1958 was a model 105, replaced later with a 3 litre, then a 2000TC, and finally a 3500. And don't forget the Triumph TR-8 and the Morgan +8. If you are familiar with the Meyer-Drake/Offenhauser engines, the Moretti 750 was a miniature version - a shrunken Indy roadster widened enough for two (small) seats. Current toy is another alloy V-8, an AMG 500SE from the boys in Stuttgart.

How about a compromise on the castor? Add 4 ounces instead of three. That will still leave the nitro at 4.85%, and bring the total oil up to 20.48% with 3.03% castor in the fuel. That's assuming the Wildcat starts at 18% synthetic.

Bill.

yard-dart

My Feedback: (35)

The never-ending debate of YS being better than Saito, will be like I said, never ending. Just because YS came out with an alteration by adding a supercharger/airchaimber/whatever to their engines, giving it more power, some people have began to worship these engines. YS is simply a status symbol. Sure, they are great running, powerful engines 'when running right'. For the average Joe like me, who wants to go to the airfield, crank up and fly, Saito is, by far, the most dependable, reliable, simple, easy- to use, powerful engine in it's class. YS is not in it's class! Supercharged, Hellooo! Saito doesn't need a supercharger. They are perfect just like they are! Dollars compared to dependability......Saito is, by far, the better deal and better engine.

Simon Jones

Bill I know the TR8 qite well and the Morgan (whatdo you think about the new Aero 8). The TR7 was my dream car as a boy until I found out what the TR8 was and then that became my favourite. Never played with an AMG but they look like a laugh from the stats. What's it like for carting models about? I've got to be boing what with having a young family (and no never ending supply of cash) so I've got an Audi A6 Quattro Avant. It's good for karting around large models, even ifit tends to foam the fuel a bit. Best to date is 6 planes, a heli and all the other parafinalia.

I was thinking 3oz of castor from an earlier calc, but if you say 4 oz is better that's good enough for me, and yes the wild cat is starting with 18% synthetic. The suggetsion is the 5% nitro is really at the top of the range for the MVVS with the timing apparently set for fuels in the 0-5% range.

Now I know that this is a bit of a tangent for his thread but the above bings me onto another possible point of interest in the, what fuel to use, question.

Are all model engines timed for a specific nitro content?

If so does this mean that we are not gaining any real performance increase with some engines by increasing the nitro, and possibly more worrying could we actuallybe having a detrimental effect on performance or damaging our engines with the high content fuels?

On one of my fun flys with a magnum 36 and pipe I've used everything up to 30% nitro, I'm now moving back to using fuels in the 5-10% range as this actually flies the model better, particularly when you are trying to hover etc.

sj.

William Robison

My Feedback: (3)

Simon:

Not familiar at all with the Aero 8 model, but the AMG requires care when carrying a wing in the front leaning against the seat. Careless application of the throttle makes it fly without being attached to the fuselage, and damage happens when it stops against the rear window. Tends to crush the tips. Haw.

But the power does have a price. On a good day it gives me 8 miles per gallon of fuel, or in European measure that's almost 30 litres per 100 kilometers. US gallon, of course. an Imperial gallon is 9.6 miles.

Most European model engines are set up for no nitro, or up to 5% at most, and even that 5% is probably a waste. This is for two reasons, and I think the second is due to the first - 1) the high price of nitromethane on the continent, and 2) the FAI specifying zero nitro for international competitions where maximum engine performance is required.

In the rest of the world nitromethane is a lot less expensive, for example US$45/gallon here. And since the nitro gives a definite performance increase when the engine is set for it, US and Asian engines are generally set to give maximum power at 25% to 30% nitro. These can be adjusted to be efficient on zero to five nitro, just as the European engines can be set for higher nitro. And some engines, the little Norvels for example, have adjusting the compression as part of the instructions supplied with them.

What it comes down to is that if you want absolute max power, play with the engine and fuel. For normal sport flying I don't think it's worth the effort. I fly with 15% Omega as my standard fuel, using the same fuel in everything except the little Cox engines - they aren't happy at less than 25%.

Just my thoughts and opinion.

Bill.

radray

I have a 10 y/o YS 1.20 SC I fly almost every weekend, at least 1500 flights (Magnum #1, OS-F, APC 15x13n or 15x12), almost never touch the needles. Very dependable, reliable and powerful engines.

captinjohn

That sure is a lot of flying...1500 flights...what plane do you have it on? Thanks Capt,n

rajul

My Feedback: (58)

MPX, what parts did you need to change in the ys 1.20 over the 10 years of use ?

radray

It started out in a USA Star, then went into a Dr. Jeckyll, and for the last 5 or so years has been in a Zimpro FAI Viper (the Hyde mount was also changed out about the same time as the Viper). Early on the magnesium piston was changed to Al, and I use Leak Free gaskets, and I have the rear bearings changed every couple years. Mike McCormick has performed the last couple services and he said the engine looked great on the inside.

rajul

My Feedback: (58)

Hi MPX, did the pump membrane give you any problems ?

coomarlin

My Feedback: (1)

If Saito is Mercedes, YS is Porsche, and OS is BMW, what does that make Magnum and TT 4 strokes? Renault and Peugeot.............