A starter is an electric motor needed to turn over the engine to start it.
A starter consists of the very powerful DC electric motor and starter solenoid that is attached to the motor (see the picture).
A starter motor requires very high current to crank the engine, that's why it's connected to the battery with large cables (see lower diagram).
The negative (ground) cable connects "-" battery terminal to the engine block close to the starter.
The positive cable connects "+" battery terminal to the starter solenoid.
The starter solenoid works as an electric switch - when actuated, it closes the circuit and connects the starter motor to the battery. At the same time, it pushes the starter gear forward to mesh with the engine's flywheel.

How the starting system works:
When you turn the ignition key to the "Start" position, the battery voltage goes through the starter control circuit and activates the starter solenoid, which in turn energizes the starter motor. The starter motor cranks the engine.
A starter can only be operated when the automatic transmission shifter is in "Park" or "Neutral" position or if the car has a manual transmission, when the clutch pedal is depressed.
To accomplish this, there is a Neutral safety switch installed at the automatic transmission, (or at the clutch pedal).
When the automatic transmission is not in "Park" or "Neutral" (or when the clutch pedal is not depressed), the neutral safety switch is open and the starter relay disconnects the starter control circuit.

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A variety of NDT techniques are available for detection and characterisation of defects in welds. All NDT techniques are based on physical principles. Nearly every form of energy is used as probing medium in NDT. Likewise nearly every property of the materials to be inspected has been made the basis for some method or technique of NDT. In general, NDT methods involve subjecting the material (being examined) to some form of external energy source (X-rays, ultrasonic, thermal wave, electromagnetic fields etc.) and analysing the detected response signals (refracted energy, induced voltage and diffracted energy).

Inspection of welds

The beam of radiation must be directed to the middle of the section under examination and must be normal to the material surface at that point, except in special techniques where known defects are best revealed by a different alignment of the beam. The length of weld under examination for each exposure shall be such that the thickness of the material at the diagnostic extremities, measured in the direction of the incident beam, does not exceed the actual thickness at that point by more than 6%. The specimen to be inspected is placed between the source of radiation and the detecting device, usually the film in a light tight holder or cassette, and the radiation is allowed to penetrate the part for the required length of time to be adequately recorded.

The result is a two-dimensional projection of the part onto the film, producing a latent image of varying densities according to the amount of radiation reaching each area. It is known as a radiograph, as distinct from a photograph produced by light. Because film is cumulative in its response (the exposure increasing as it absorbs more radiation), relatively weak radiation can be detected by prolonging the exposure until the film can record an image that will be visible after development. The radiograph is examined as a negative, without printing as a positive as in photography. This is because, in printing, some of the detail is always lost and no useful purpose is served.

Before commencing a radiographic examination, it is always advisable to examine the component with one's own eyes, to eliminate any possible external defects. If the surface of a weld is too irregular, it may be desirable to grind it to obtain a smooth finish, but this is likely to be limited to those cases in which the surface irregularities (which will be visible on the radiograph) may make detecting internal defects difficult.

After this visual examination, the operator will have a clear idea of the possibilities of access to the two faces of the weld, which is important both for the setting up of the equipment and for the choice of the most appropriate technique.

Defects such as delaminations and planar cracks are difficult to detect using radiography, which is why penetrants are often used to enhance the contrast in the detection of such defects. Penetrants used include silver nitrate, zinc iodide, chloroform and diiodomethane. Choice of the penetrant is determined by the ease with which it can penetrate the cracks and also with which it can be removed. Diiodomethane has the advantages of high opacity, ease of penetration, and ease of removal because it evaporates relatively quickly. However, it can cause skin burns.

RADIOGRAPHY
As the X-ray absorption coefficient depends strongly on material density, radiography is particularly effective at detecting volumetric defects, which contain either extra mass or missing mass (such as slag inclusions or porosity). The benchmark for radiographic inspection of welds is still high-quality film radiography and good radiographic practice is now enshrined by a series of national standards, covering factors such as choice of voltage, film–source distances, intensifiers, image quality indicators, film density, film processing, etc. There have been a number of advances in radiography over the past 10–15 years including more reliable microfocus tubes, real-time radiography and the application of image processing techniques to sharpen the image and to increase the contrast. For better definition of defects and delectability of small defects like micro-cracks in thin components and complex geometries, high resolution micro-focal X radiography has an edge over the conventional radiography. One of the important applications of micro-focal radiography is evaluation of tube to tube sheet weld joints of PFBR steam generators (made by welding between pull out of tube sheet and the tube).

The most significant recent development in radiography has been the real-time radiography. Real time radiography or fluoroscopy differs from conventional radiography in that the X ray image is observed on a fluorescent screen rather than recorded on a film. Fluoroscopy has the advantages of high speed and low cost of inspection. Present day real time systems use image intensifiers, video camera and monitor. The principal advantages of real-time radiography are that it is well suited to automation and the images of the component under inspection are available directly without time delays due to film exposure and processing. Furthermore, as the images are provided in digital form, image processing and automatic defect interpretation softwares can be readily incorporated into the inspection system. On-line monitoring of welding is another possibility by real time radiography. Direct examination of the welds in real time saves films and time and is found to be cost effective in the long run [5]. The use of microfocal units in conjunction with image intensifying system greatly enhances the versatility and sensitivity of the real time radiography, by way of zooming or projection magnification.

With the advent of image processing systems, the sensitivity that can be achieved is comparable to film sensitivity. The stored or digitized X-ray image can be subjected to image processing and enhancement techniques such as contrast stretching, edge enhancement, special filtering, differentiation, averaging, and pattern recognition for enhanced detection of defects and also for obtaining quantitative information. The versatility of image processing is that this can be performed in real time as well as on film images. Figures 1(a) and 1(b) show typical radiograph of a weld joint. Figure 1(a) gives the raw image wherein penetrameter wires are not clearly seen. After contrast stretching and image enhancement (Fig. 1(b)), the lack of penetration can be seen and the wire penetrameters can be identified thereby increasing the sensitivity.

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Total Motorcycle's 10 Step Guide to Winterizing your motorcycle

Storing your bike for winter

Well, it's that time of year again! Soon the snow will be falling and the motorcycles will be tucked away for the winter

And each spring your dealer's phone will ring off the wall with customers who did not store the ol' bike properly and now wonder why it won't run.

Some preparation now will ensure that you are out riding in the spring instead of waiting in the dealer's lineup.


1. Location - where are you going to put it?

One solution may be to ask your dealer if he offers a storage program. This is ideal because he will often prep, store, and have the bike ready to ride when you are ready again. If you decide to store it yourself, you will need a place that is dry and out of harm's way.

When possible. Chose a location away from windows. The ultraviolet light can fade paint and plastic parts. Direct sunlight can raise the ambient temperature of the storage area which will promote condensation when the sun goes down, so cover plain glass with some sort of opaque material. Also, cover your bike with a specially designed bike cover not a sheet or a tarp. Why? Because a sheet absorbs moisture and hold it against metal surfaces and then rust forms. Also, damp fabric will breed mildew and this may attack the seat material. A tarp prevents moisture from getting in but it also prevents it from getting out. Moisture trapped will condense on the bike and then the rust monster is back!

A specially designed motorcycle cover is made of a mildew resistant material. The material is slightly porous, so it can breathe.

2. Change The Oil

Tip: Just like cars a colder winter grade oil will allow your bike to start easier in colder weather. If your motorcycle runs ok with a cold winter grade oil (5w30) then changing the oil to this grade will help startup and running in spring.

Even if the oil is not due for a change, byproducts of combustion produce acids in the oil which will harm the inner metal surfaces. Warm the engine to its normal operating temperature, as warm oil drains much faster and more completely.

While you are at it, why not change the filter too? Add fresh motorcycle grade oil. Remember to dispose of the drained oil and old filter in a responsible manner. What to do with the old oil? Recycle it. Most stores you have purchased the oil from will take it back free of change to be recycled.


3. Add Fuel Stabilizer And Drain Carbs

Tip: You only need to drain the carbs if your motorcycle will be stored more than 4 months. Otherwise just add fuel stabilizer to the gas tank, run the bike for 10 minutes so it mixes and gets into the carbs.

Fill the tank with fresh fuel, but do not overfill. The correct level is when the fuel just touches the bottom of the filler neck. This gives enough room for the fuel to expand without overflowing the tank when temperature rises.

Shut off the fuel petcock and drain the carburetors and the fuel lines. Add winterizing fuel conditioner to prevent the fuel from going stale, and help prevent moisture accumulation. Stale fuel occurs when aromatics (the lighter additives) evaporate leaving a thicker, sour smelling liquid. If left long enough, it will turn into a gum, plugging the jets and passages inside your carbs!



4. Lube the cylinder(s)

Tip: You only need to do this if your motorcycle will be stored a very long time (6 months or more)

Because gasoline is an excellent solvent and the oil scraper ring has done its job, most of the oil from the cylinder walls have been removed since the last time the engine was run. If the cylinder wall is left unprotected for a long period of time, it will rust and cause premature piston and ring wear.

Remove the spark plugs and pour a tablespoon (5 cc) of clean engine oil or spray fogging oil into each cylinder. Be sure to switch off the fuel before you crank the engine or else you may refill the drained carbs! Also, ground the ignition leads to prevent sparks igniting any fuel residue. Turn the engine over several revolutions to spread the oil around and then reinstall the plugs. Refitting the plugs before cranking the engine could result in a hydraulic lock if too much oil was used in the cylinder.



5. Battery Storage

The battery must be removed from the motorcycle when it is in storage. Motorcycles often have a small current drain even when the ignition is switched off (dark current), and a discharged battery will sulfate and no longer be able to sustain a charge.

A conventional battery should be checked for electrolyte level. Add distilled water to any of the cells that are low and then charge the battery.

Battery charging should be performed at least every two weeks using a charger that has an output of 10% of the battery ampere hour rating. For example if the battery has an AH rating of 12 (e.g. 12N12A-4A-1 where the 12A is 12 amp hours), then the charge rate of that battery should not exceed 1.2 amps. A higher charge will cause the battery to overheat. Charge the battery away from open flame or sparks as the gas (hydrogen) given off a battery can be explosive. Elevate the battery and keep it from freezing. Exercise the proper caution appropriate to caustic substances.



6. Surface Preparation

Waxing and polishing the motorcycle might seem like a waste of time since you are putting it away and no one will see it. But applying wax is a very important part of storing a motorcycle.Wax will act as a barrier against rust and moisture.

Don't forget to spray any other metal surfaces (such as the frame or engine) will a very light spray of WD-40. This will keep these areas shiny and protect from corrosion as well.



7. Exhaust and Mufflers

Exhausts/Mufflers are known to rust fast when they are not used. So making sure they are properly stored for the winter on your bike will save them from an early rusty death. Spray a light oil (such as WD40) into the muffler ends and drain holes. Lightly stick a plastic bag (shopping bag is fine) into the end of each muffler hole (to keep moisture from getting inside the exhaust). Then cover each muffler with another plastic bag to keep outside moisture off.



8. Tires

Check both front and rear tires with your air pressure gauge. Make sure each tire is properly inflated to the maximum recommend pressure. As it gets colder, air condenses in your tire so it is important to pump them up as to keep your tires healthy. Rubber is a flexible material and does not like to freeze (it cracks when it freezes). Placing 1/4"-1/2" piece of cardboard or wood board under each tire will help keep the rubber raised up from a freezing floor.

DO NOT use a tire dressing on tires (such as Armor-All or tire cleaning foam) as this will make the tires hard and slippery.



9. Service all fluids

If the brake or clutch fluids haven't been changed in the last two years or 18,000 km (11,000 miles), do it now. The fluids used In these system are "hygroscopic" which means that they absorb moisture. The contaminated fluid will cause corrosion inside the systems which may give problems when the motorcycle is used next spring. Be sure to use the correct fluids and note the warnings and instructions in the service manual. If you don't have the experience to service these systems, contact your dealer, he will be happy to assist you.

If your motorcycle is liquid cooled, the coolant requires changing every two years or 24,000 kms (15,000 miles). Make sure that the engine is cool enough to rest your hand on it before draining the system and please dispose of the coolant responsibly. Coolant/antifreeze is available from your dealer and has been developed to provide the correct protection for your motorcycle engine. Mixed 50/50 with distilled water will ensure a clean system for the next two years or 24,000 kms (15,000 miles).



10. Cover it.

Now you can cover the bike with the cycle cover and look forward to the first warm day of spring.



Back On The Road

Before you head out onto the highway, there are a couple of things to do. First, remove the cover and put it where you can find it again. Talking of finding things, locate the (charged) battery and reinstall it connecting the positive (+) cable (red) before the (-) negative and covering the terminals with the plastic covers. Recheck all fluid levels and turn on the fuel. Check for anything wrong on the motorcycle (cracked tires, broken parts/plastic, leaking oil). Set the tire pressures back to riding specs and you are ready to fire up.

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