Some of the modern motorcycles use apparently archaic, low-tech air-cooled engines. Yet all these motorcycles are more desirable for it. From the single-cylinder Tiger Boxer 250 RS or small 250cc V-twin Lifan Custom V250 to the big V-twin air-cooled Ducati's and Harley's. So lets talk about air-cooled advantages...

You like simplicity, as if offering the first words of a life story. A air-cooled motorcycle weights less compared to a motorcycle with a liquid-cooled engine. You have to admit. All that liquid-coolant is a heavy old lump, isn't it? Throw in radiators, hosing and the liquid-coolant itself and you're looking at 5 to 10 kilogram more depending on the engine size. - so there's not much in it. And of course air-cooled has a lower maintenance...

The myth that air-cooled engines don meet modern emission standards is just not true. Air-Cooled engines do really well on emission, they warm up and become efficient much more quickly. Most modern air-cooled engines are just a micron away, while still breathing by a carburetor, from meeting previous emission standards, though they need a catalytic converter for the current Thai emission standard.

On the left-hand side of your motorcycle, the need for the gear lever to meet the foot at just the right position is very important because the device works in two directions. Your foot has to go smoothly under the lever to lift it and just as easily it has to flow over the top of it to shift down. Correct gear lever positioning can also be affected by the type of footwear you choose to ride in.

In a recent encounter I was asked to cut and weld the gear and brake levers to suit a rider who was unhappy with the position of the controls on their new mount. It was while watching the rider's action that the reason for their discomfort became obvious. The pair of new boots that had been purchased at the same time as the motorcycle had a rather large heel on them, which was restricting how far the rider's foot could be moved forward, therefore making the lever action uncomfortable. What price fashion? Is the footwear more important than the mechanical action? What would you change?

The point is that you must feel comfortable and I have seen many examples, usually on older motorcycles, where there has been a need to resort to the hacksaw and welder to achieve a reasonable lever action.

Sure, you could have your motorcycle garage or local motorcycle shop swap your motorcycle chain for you, but then you'd miss myriad chances to get greasy and pinch off a few hundred Thai baht. Assuming you're still interested, here's the easy way to break and replace your motorcycle chain.

Yes, naturally, there are tools. We use Motion Pro's Chain Breaker tools, because it's versatile, rugged and, well, we have one. These days, the chain manufacturers are trying to get owners and service establishments away from clip-style master links in favor or riveted links in the belief that riveted items are stronger and more durable.

You've got the get the old chain off first. The vast majority of modern motorcycles come with endless O-ring chains, and this type of chain requires removal of a roller pin to get the chain off the motorcycle.

Find an unobstructed run of the motorcycle chain and set the chain tool in place. Sometimes it's even easier to bust a link on the rear sprocket. For clarity, we're using the pin extended from the mandrel where it contacts the pin; you will want to wind the head right up against the side plate, and wind the center pin in from there. Some motorcycle chains may require grinding of the pin head beforehand, but the mighty Motion Pro Chain Breaker tool had its way with our #525 motorcycle chain with no problem.

This Suzuki GSX-R1000 fender eliminator kit was kindly supplied by Cheap Cycle Parts and you get pretty much everything you need for the job – apart from the tools obviously. Before you go ripping off your original fender and number plate brackets, just remember that they're there for a reason... they prevent all the dirt and stones from flicking up and damaging your undertail, plus reduce the rain from spraying up your back off the rear tire.

Now that we have that out of the way, the first job you need to do is remove the original fender. The Suzuki GSX-R1000 fender is very simple. There are only four bolts holding it on and it only has two small wires for the number plate light because the indicators are in the seat unit.

After removing the original Suzuki GSX-R1000 fender, place the new fender eliminator bracket up against the holes to make sure it fits. With that done, disconnect any wires.

If you say 'turbo' everybody gets that grin on his face, but do they know how it really works? A turbocharger is a simple mechanical device that uses a compressor to force more air into the engine. The more air in, the more power you get out. It's a mechanical version of a forced airbox, like all sportsbikes now come with.

A turbo has two turbines in the motorcycle's exhaust system. As the exhaust gases escape the engine at speed, they turn these turbines, which in turn drive a compressor. This compresses the air and feeds it into the engine, making more power.

The neat thing is that the faster the engine revs, the faster the exhaust gases will spin the turbines, creating more compressed air and more power. It's almost self-perpetuating.

So why aren't turbo-charger's more common on motorcycles? While most cars, and all diesels, are turning towards turbos, the popularity of motorcycle turbos never recovered after the high profile failures of the early '80s.

Petrol is the principal fuel for spark ignition engines. It is a hydrocarbon fuel blended to balance the requirements of engines – acceptable performance with fuel economy and low emissions. The fuel must provide easy starting capabilities within a wide range of temperatures, allowing the engine to warm up quickly, accelerate smoothly, while burning cleanly without leaving abrasive residues of fouling gums.

Therefore, petrol must be volatile to enable a combustible mixture with air. The stoichiometric air/fuel ratio is 14.7:1, higher than many other fuels because its percentage by weight of oxygen is zero. For comparison, the stoichiometric ratio for methanol is 6.4:1 while its oxygen content is 49.9 percent.

Erratic combustion causes engine damage and increased emissions. This circumstance can be avoided by a fuel with an octane rating sufficiently high so as to permit it to burn smoothly without knocking. To achieve maximum power, an engine must run on the edge of the lean condition – just short of detonation. Knock testing determines the octane rating of a fuel.

To measure octane numbers, the fuel industry developed in the early '30s a single cylinder, variable compression ratio knock test engine, often referred to as a CFR engine. This type of engine was manufactured by the Waukesha Engine Company, and is still in use today.

In our second part of tuning a carburetor, we look more closely at the Jet Needle and the Lean and rich condition.

Tuning the Jet Needle

Maybe a definition is in order before we go any further. The jet needle is that straight, needle-looking thing that you see in the throat of the carburetor when the slide rises in the carburetor bore. The jet needle controls fuel flow from just above idle to about three-quarter throttle. Essentially, the jet needle rises and lowers in the needle jet portion of the emulsion tube, which is a predetermined diameter, and the taper on the needle regulates the fuel flow during partial throttle operation.

It is unlikely that you need to change the jet needle from the one supplied. In the unlikely case that you do, you should be aware of how it works and how to tell if the one you have is too large (leaner) or too small (richer) for your particular engine setup. The initial straight portion of the jet needle affects the mixture from idle to approximately quarter throttle, at which point the needle's tapered portion takes over.

How often do you do 250km/h, or more? Obviously here at Motorcycle Thailand, we all hit this speed most mornings on our commute through downtown Bangkok, hahaha. Okay lets keep it serious, the last time one of use was doing 250km/h is some time back and was surely not something we do daily...

But even we would admit that maximum speed is generally less useful than acceleration. Lowering the gearing on your motorcycle can make a massive difference to the performance, particularly on many modern sportsbikes, which tend to have revvier, top-end-biased delivery.

When you motorcycle goes down in the water, whatever it is a, rice field, river or just to deep flooding of some streets during the monsoon. Depending on how deep in the water you could have a serious problem, if not acting quick. The first thing is to hit the kill switch and then remove the motorcycle from the water as soon as possible. This may need the help of fellow riders or sidewalk locals.

As soon as you are out of the water with your motorcycle, work quickly to remove the spark plugs and turn the engine over several times to remove water from the engine. Use WD40 to spray into the cylinders and dry off the spark plugs. Then douse your starter motor, alternator and any other electrical components with WD40. This will often involve removing your fuel-tank, so learn how to do this. Depending on the amount of water and time spent under water, you will likely need to change your oils.

There are so many different types of systems for operating the rear brake that it would be impossible to address them all, but most are variations on two themes. Theme one is the drum brake, while theme two is the hydraulic disc brake.

Your typical drum brake may have an old-fashioned design, but there's a lot to be said for its simplicity, economy and effectiveness. Nowadays, drum brakes are most commonly used on smaller road and trail motorcycles, but they're also found on some cruisers models.

The drum brake is activated by cable or rod from the foot lever and will usually have an adjuster at the brake end. An important consideration to bear in mind when adjusting a food-activated brake is that, just like the hand lever type, there needs to be a degree of freeplay to ensure the does not bind on.

Drum brakes are affected by heat and this tends to make the brake components expand, so it worth remembering that the freeplay should still be there when the brake is hot – just don't burn your fingers when you check. And as with a hand lever, the activation of the brake pedal should be a natural act – your foot should be able to move on and off the pedal with the least amount of input. You should also have good leverage on the pedal.