Nickel and nickel-alloy weld metals do not flow and spread like steel weld metal. The operator must direct the flow of the puddle so the weld metal wets the joint sidewalls and the joint is filled appropriately. This is sometimes accomplished by weaving the electrode slightly. The amount of
weave will depend on such factors as joint design, welding position, and type of electrodes. A straight drag (stringer) bead deposited without weaving may be used for single-bead work, or in close quarters on thick sections such as in the bottom of a deep groove. However, a weave bead is generally desirable. When the weave progression is used, it should not be wider than three times the electrode core diameter. Regardless of whether the welder uses weaving or the straight stringer technique, all weld beads should be deposited such that they exhibit the recommended slightly convex surface contour.


When used properly, SMC flux covered welding electrodes should exhibit a smooth arc and no pronounced spatter. When excessive spatter occurs, it is generally an indication that the arc is too long, amperage is too high, polarity is not reversed, or that the electrode has absorbed moisture. Excessive spatter can also be caused by magnetic arc below.

When the welder is ready to break the arc, it should first be shortened slightly and the travel speed increased to reduce the puddle size. This practice reduces the possibility of crater cracking and oxidation, eliminates the rolled leading edge of the crater, and prepares the way for the restrike.

The manner in which the restrike is made will significantly influence the soundness of the weld. A
reverse or “T” restrike is recommended. The arc should be struck at the leading edge of the crater and carried back to the extreme rear of the crater at a normal drag-bead speed. The direction is then reversed, weaving started, and the weld continued. This restrike method has several advantages. It establishes the correct arc length away from the unwelded joint so any porosity resulting from the strike will not be introduced into the weld. The first drops of quenched or rapidly cooled weld metal are deposited where they will be remelted, thus, minimizing porosity.

Another commonly used restrike technique is to strike the arc on the existing bead In this manner, the weld metal likely to be porous can be readily removed by grinding. The restrike is made 1/2 to 1 in. (13 to 25 mm) behind the crater on top of the previous pass, and the restrike area is later ground level with the rest of the bead. This technique is often used for applications requiring that welds meet stringent radiographic inspection standards. It is also noteworthy that it is much easier for welders with lesser levels of skill to produce high quality welds than they can using the “T” restrike technique.

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The modern car industry is run by some of the best brains in the world. These people are constantly getting feedback from the consumers and this helps them refine their products over time. They also fund some of best researchers who continuously come up with ideas and innovations. This again means that cars get better and better. Therefore as a buyer one finds the highest levels of performance, looks and passenger comfort. Which is great but there is one problem. It is rare that the same car model comes out on top in terms of all three, looks, comfort and performance.

So when you are choosing a car you need to make a decision as to, on which front will you settle for the less than best option. Will you choose a car that doesn't quite look the best or doesn't have the most comfortable ride or doesn't have the best in class performance.

One option is you can choose the best looking car if style is very important to you and settle for a lesser performance. Unless you can come up with an innovation yourself you will have to make a compromise. So what is the solution?

The answer is simple. You can come up with an innovation yourself. Choose a car that performs the best and use the latest body kits to make it look stylish. You will find that car body kits can breathe excitement into an other wise dull car. Therefore you will be able to get the car performance you want and you will get more than great looks. Because with body kits you will be able to not only improve the looks of your car but you will be able to personalize them as well. Your car will reflect your personality and taste.

Body kits are quite light and will not affect the performance of your car much. If you choose carbon fiber composite based body kits they are very light and hardly affect the performance at all. You can choose from a wide range of body kits online and give your car a stylish cutting edge look. You can find the latest body kits at http://www.ilovebodykits.com

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Sparkplugs:
Types
You may of noticed that there are hundreds of types, sizes and brands of spark plugs on the market. But out of that huge selection, only a handful will work with the motorcycle engine you own. Also different brands (NGK, Bosch, DENSO, Champion, Esc) will work better on different types of engines.

As a general rule of thumb, use the sparkplug your manufacturer recommends for your motorcycle (same brand and part number). Unfortunately some spark plugs are very specific to a type of engine and make only for that engine such as the NGK ME8 for $34.23 per sparkplug, compared to the "normal" price of $2-4 per sparkplug.

Reading a spark plug correctly: (clickable chart)
There are two different main ways to read a spark plug. #1. The first way is to just unscrew it out of the engine and take a look at the end of it, matching the chart below. #2. The second way is the same as #1 except you go for a really hard high revving ride on the bike, pull over and then unscrew each plug to read them. (Just make sure to use gloves as they will be very hot).

A spark plug can easily and quickly tell you the condition of an engine (good or poor), how it is running (rich or lean) and how much it will cost to fix it.


CARBON DEPOSITS
Symptoms: Dry sooty deposits indicate a rich mixture or weak ignition. Causes misfiring, hard shifting and hesitation.

Recommendations: Check for a clogged air element, high float level, sticky choke and worn ignition points. Use a spark plug with a longer core nose for greater anti-fouling protection.

OIL DEPOSITS
Symptoms: Oily coating caused by poor oil control. Oil is leaking past worn valve guides or piston rings into the combustion chamber. Causes hard starting, misfiring and hesitation.

Recommendations: Correct the mechanical condition with necessary repairs and install new plugs.

TOO HOT
Symptoms: Blistered, white insulator, eroded electrode and absence of deposits. Results in shortened plug life.

Recommendations: Check for the correct plug heat range, over-advanced ignition timing, lean fuel mixture, intake manifold vacuum leaks and sticking valves. Check the coolant level and make sure the radiator is not clogged.

PREIGNITION
Symptoms: Melted electrodes. Insulators are white, but may be dirty due to misfiring of flying debris in the combustion chamber. Can lead to engine damage.

Recommendation: Check for the correct plug heat range, over-advanced ignition timing, lean fuel mixture, clogged cooling system and lack of lubrication.

HIGH SPEED GLAZING
Symptoms: Insulator has yellowish, glazed appearance. Indicate that combustion chamber temperatures have risen suddenly during hard acceleration. Normal deposits melt to form a conductive coating. Causes misfiring at high speeds.

Recommendation: Install new plugs. Consider using a colder plug if driving habits warrant.

GAP BRIDGING
Symptoms: Combustion deposits lodge between the electrodes. Heavy deposits accumulate and bridge the electrode gap. The plug ceases to fire… resulting in a dead cylinder.

Recommendation: Locate the faulty plug and remove the deposits from between the electrodes.

NORMAL
Symptoms: Brown to grayish-tan color and slight electrode wear. Correct heat range for engine and operating conditions.

Recommendations: When new spark plugs are installed replace with plugs of the same heat range.

ASH DEPOSITS
Symptoms: Light brown deposits encrusted on the side or center electrodes or both. Derived from oil and/or fuel additives. Excessive amounts may mask the spark, causing misfiring and hesitation during acceleration.

Recommendation: If excessive deposits accumulate over a short time or low mileage, install new valve guide seals to prevent seepage or oil into the combustion chambers. Also try changing gasoline brands.

WORN
Symptoms: Rounded electrodes with a small amount of deposits on the firing end. Normal color. Causes hard starting in damp or cold weather and poor fuel economy.

Recommendation: Replace with new plugs of the same heat range.

DETONATION
Symptoms: Insulators may be cracked or chipped, improper gap setting techniques can also result in a fractured insulator tip. Can lead to piston damage.

Recommendation: Make sure the fuel antiknock values meet engine requirements. Use care when setting the gaps on new plugs. Avoid lugging the engine.

SPLASHED DEPOSITS
Symptoms: After long periods of misfiring, deposits can loosen when normal combustion temperature is restored by an overdue tune-up. At high speeds, deposits flake off the piston and are thrown against the hot insulator, causing misfiring.

Recommendations: Replace the plugs with new ones or clean and reinstall the originals.

MECHANICAL DAMAGE
Symptoms: May be caused by a foreign object in the combustion chamber or the piston striking an incorrect reach (too long) plug. Causes a dead cylinder and could result in piston damage.

Recommendation: remove the foreign object from the engine and/or install the correct reach plug.

Sparkplug Caps:

Tip: Don't use decorative or spark arching type sparkplugs.

There are many different styles and types of sparkplug caps. Try to use the sparkplug cap that best matches the angle between the spark plug wire and spark plug itself. No matter what shape the spark plug cap is, is will perform the same.

Try to avoid "decorate" or spark arching type spark plug caps as they will LOWER the power to the sparkplug and you will have a weaker spark on stock systems.


Sparkplug Gap
Tip: If you use the exact same sparkplug as your motorcycle manufacturer recommends the sparkplug should be (99%) properly gapped to the correct size. Checking a gap only takes seconds to do.

Always check that the spark plug gap is compatible with the engine manufacturers specification. A gap that is too small means that the spark duration will be very quick and the spark will be thin and weak. The consequences of this may be bad starting and high exhaust emission levels. This will result in an increase in fuel consumption. If the gap is set too large, the ignition system will not be able to cope with the demands and a misfire situation will occur. Some wide gap spark plugs have a longer ground electrode to accommodate a wide gap setting. These must be used where specified, as opening up a standard plug to a wider gap setting may result in the electrodes not running parallel to each other. This could result in abnormal and premature electrode wear.

Hot and Cold Sparkplugs
Tip: It is better to fix the problem than to change the sparkplug to patch it up.

Why Hot and Cold Sparkplugs? Using a hotter or colder sparkplug can be just the fix to an engine problem. Very basely, if your motorcycle engine
is running hot then try using a colder plug, if it is running hot try a colder plug.

NGK diagram showing insulator and heat range

Hot Plug
- has a longer insulator nose length
- less heat is absorbed by the plug and transferred to the cooling system
- the plug runs at a higher temperature
- the plug is more prone to pre-ignition (if greater than 850 degrees C)
- NGK BP5ES is hotter than a BP7ES plug.
- An overheated plug will be white with brown spots.

Cold Plug
- has a shorter insulator nose length
- more heat is absorbed by the plug and transferred to the cooling system
- the plug runs at a lower temperature
- the plug is more prone to fouling (if less than 500 degrees C)
- NGK BP7ES is cooler than a BP5ES plug.
- A fouled plug will be black and sooty.

Influences to spark plug temperature
Any of the following situations can increase spark plug temperature:
-Lean air/fuel mixtures
-Increasing compression
-Forced induction (Supercharging, turbocharging or Nitrous)
-Camshaft change
-Advancing ignition timing
-Higher engine speed
-Higher engine load
-Lower air temperature (more dense air resulting in leaner air/fuel mixture)
-Lower humidity (more dense air resulting in leaner air/fuel mixture)

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