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Your Reviewer

My Credentials
So who's doing this reviewing then?

Well I've been building and flying or driving radio controlled models for over 40 years and during that time I like to think I've built up a reasonable amount of knowledge.

I'm also a qualified electronics engineer who has worked in radio frequency, analog, digital systems and software for more than three decades. In fact I designed and built my first RC set back in 1969.

For the past nine years I've also been involved in the design and manufacture of some rather sophisticated engine technology and UAV flight control systems.

So, chances are I've been there, done that and have a huge pile of tee shirts to prove it.

Right now I'm heavily into 3D flying and enjoy all aspects of the RC hobby. I may be old but I don't feel it.

In the Pipeline

Here's just a little bit of what's to come on this site...

RC explained: Demystifying terms such as PCM, PPM dual conversion, single conversion, full-range etc., this feature will explain it all.

Cheap Chinese Engines: Just how good are those cheap Chinese glow and gas engines that sell for half the price of their "brand-name" equivalent? I put several to the test.

Build your own radio gear?: Back in the old days, building your own RC gear was not uncommon and now the arrival of 2.4GHz has made it practical again.


Model engine lubricants


oils for glow engines

Most people don't give much thought to the type, brand or quantity of oil that goes into their model engines, they simply buy their fuel from the local hobby shop and leave the chemistry, physics and science to someone else.

That approach works just fine, but if you want to get the maximum life and optimum performance out of your engine, you might want to learn a little more about the oils that go into that fuel.

What does the oil do?

The oil used in model glowplug engines actually does a lot of things.

Although (as you would expect) its main job is to lubricate the moving parts and reduce wear, it also has several other jobs.

One of those other jobs is to protect the steel components from rusting when the engine is not running, a task that is not as simple as you might think.

This is because the primary component of model fuel is methanol, an alcohol that just loves to absorb water from the atmosphere and, as we know, water+steel=rust.

Another problem is that most fuels contain nitromethane, a chemical that can produce corrosive (acidic) byproducts when it's burnt. This means that the oil in your fuel not only has to prevent any metal-to-metal contact, it also has to ensure that neither the acids nor the water that form inside the engine are able to reach the steel bearings and crankshaft.

Unfortunately, some synthetic oils are not very good at protecting the steel parts of our engines from the risk of rust and corrosion. This means the manufacturer has to add special anti-corrosion agents and these are not always effective (more on this later).

How much oil is enough?

Many people probably wonder why it is that their 2-stroke lawnmower, weed-whacker or chainsaw can get by with just a tiny amount of oil in its fuel. Indeed, most 2-stroke gasoline engines need no more than 4% (25:1) and many are happy with 2% (50:1). So why is it that our glow engines are normally fed on a fuel that has between 17% and 20% oil?

Well there are several reasons for that...

Firstly, most gasoline engines are built differently to glow motors. The main area of difference are the bearings used on the connecting rod. In a 2-stroke gas motor, needle-roller bearings are used rather than the much simpler bushings found in our model engines.

Needle-roller bearings need very little oil to keep them working but a bushing needs far more. That's because the bushing relies on having enough oil to form a layer thick and strong enough to stop the two metal surfaces from touching.

Secondly, gasoline itself has a small amount of lubricating ability, but methanol has virtually none. This means that gasoline effectively has a small degree of oiliness built into it, which reduces the amount of oil you have to add.

Another reason that's seldom appreciated for the hi-oil ratios we run in model engines is simply because that's the way it's always been. Back in the early days of model engine design and production, metals, machining and design simply weren't as good as they are today. Nor were the oils we used.

This meant that very high oil ratios (20%) were always recommended to provide a suitable safety-margin against engine damage.

But things are different today.

Now we have CNC-controlled machinery, far more exotic alloys and plating processes, and oils that offer vastly improved protection and lubrication.

Yet many manufacturers still recommend 20% oil and most commercial fuels contain at least 17% (at least in the USA).

However, given the advances in both engineering and oil technology, it is now possible in some cases to run as little as 10% oil without compromising the life or performance of an engine.

So why do manufacturers still recommend such high oil contents?

Well only a few advanced synthetic oils are good enough to allow a lower oil percentage to be safely used and since the engine manufacturer has no control over the oil, they play it safe and assume you're using an inferior brand.

Our club has been running its engines on just 12% of a hi-quality oil for nearly 18 months and there has not been a single lubrication-related problem in that time.

What we have noticed is that our engines run cooler, we get longer flight times for a given tank size, a lower and more reliable idle, easier starting (especially in winter), less exhaust residue on our models and several hundred RPMs more power than when used with higher percentages of lower-quality oil.

In fact, it's been our experience that when a lower percentage of a very hi-quality oil is used, it's like adding an extra 5% nitromethane, so that a 5% fuel performs like a 10% one. With nitro prices currently going through the roof and availability becoming an issue, that's a great way to save money without sacrificing performance.

So what makes a good oil and what are the choices? Read on...

On to part 2

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The Blog

Updated: 20 Sep 2012
Here's a blog that will keep you informed just what's going on behind the scenes at RC Model Reviews and also tells you a little more about myself.

How compatible are 2.4GHz RC systems?

23 Mar 2010
How come there's no compatibility between different brands of transmitters and receivers? Why can't you use a cheap Chinese receiver with your Futaba FASST radio?

How to get a product reviewed here

4 Mar 2010
Since this has become a very frequently asked question, I've posted this simple guide to getting your product, or a product you're thinking of buying reviewed here at RCModelReviews

How servos work

Useful information on what's inside your servos and how they work.

The Good Oil

Important facts you should know about the oils that are used in our model engine fuels.

Heads-Up: 2.4GHz RC systems tested

How well do five different 2.4GHz systems stack up when hit by interference? The answers are here, with more to come.

Review: Bushnell's $80 Speed Gun

Yes it does work on model airplanes but there are some limitations involved with this bargain-basement radar speed gun.

Review: TowerPro MG995 servo

These are possibly the world's worst servos, find out exactly why you should avoid these boat-anchors at any cost.

Review: SK90


It's cheap but can it really stack up against other glow engines in the .90 market? Find out in this review.

Review: iMax 9X 2.4GHz radio

How does this cheap 9-channel 2.4GHz radio system perform when compared to big-name systems that can cost two or three times as much? Have the Chinese finally developed a real contender with the iMax 9X?

2.4GHz Explained

Does all this 2.4GHz stuff have your head spinning? 2.4GHz

I've done my best to demystify the whole subject so if you feel like a bit of learning, this is the stuff for you!

Fix That Engine!

How can you tell when your engine needs new bearings? Who has the best prices and service on replacements? Just how do you change them? Get all that information and watch a great video tutorial anyone can follow.

Chinese Servos - How do they stack up?


The Chinese are now churning out a huge number of very reasonably priced no-name servos. But are they any good?

Baffled by batteries?

Batteries Nicad, NiMH, Li-Ion, LiPoly, LiFePO4, A123... the range of different battery types has never been greater. So how do they differ and what type should you be using?

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