[Discussion] Technical - Spark Plugs

[ghost04]

mine is right from the start...only the ignition is good. plug is clean as new when i took out.

[FUbike]

mine is right from the start...only the ignition is good. plug is clean as new when i took out.

 

how come everyone have no problems like mi? i really wana get OWS again but 25bucks very ex lei...and if it happens again, how? die lo....

[biting_point]

i like it too, gave alot of power! but rpm getting lower and bike dies easily den realising it's the plugs tat burnt up. did urs burnt to super super black? seriously i never seen plugs burnt till so black b4...

 

there's many factors causing the foul plug.. have you tuned and adjust air/fuel mixture after you changed the plugs?? i always see my mech adjust them after changing the plugs, even he just takes them out to check..

the last bike i saw was a blackbird..

 

other factors like plug cap, etc..

 

how you highlight your plug issues to your bikeshop? i personally know and chatted with the OWS distributor, they are very confident abt their products.. not to say your plug turned into BLACK BLACK!!

[SMR]

i used ows b4 and the feeling was good at first but something happened. cos i was riding the exhuast came out popping sound and the bike dies when i stop at traffics. Try starting again and dies again if i dun blow.. and i went to HKL to check and was the ows he told mi... it was totally burned and black..never seen that before... wondering izit i whacked too much? i'm not saying the plugs are to be blamed....

 

Bro, your bike just need some tuning... The problem is not with OWS spark plug, it's because your carburettor wasn't tuned properly...

[hit.man]

The spark plug won't become foul on its own. Its due to many factors. Like many others mentioned.. could be tuning/carb prob. Get that sorted out and your plug s should work fine...

[skazuz]

i'm using the ah boy ngk spark plus 30000km lioa no prob leh..still werking fine..

 

now the reviews for ows like very cialat i also scared leh wanna change to ows..

 

cheers

skazuz

[FUbike]

i'm using the ah boy ngk spark plus 30000km lioa no prob leh..still werking fine..

 

now the reviews for ows like very cialat i also scared leh wanna change to ows..

 

cheers

skazuz

 

bro, dun worry...i DIDNT say OWS not good, i go tuning soon and OWS is a good plug... after tuning i'll still using OWS.... like they say maybe didnt tune.... sorry OWS!!

[FUbike]

Bro, your bike just need some tuning... The problem is not with OWS spark plug, it's because your carburettor wasn't tuned properly...

 

sure! i'm going for tuning....

[biting_point]

seriously, i think these negative comments dun do justice to the plugs..

 

anyway, the $100 pomo is still on.. where got iridium plugs plus engine oil and oil filter at $100 one? give it a try in your next oil change, and post your comments here..

[FUbike]

seriously, i think these negative comments dun do justice to the plugs..

 

anyway, the $100 pomo is still on.. where got iridium plugs plus engine oil and oil filter at $100 one? give it a try in your next oil change, and post your comments here..

 

yup!!! at Unique....been there:P

[edmundino]

Well, firstly, you guys gotta understand what the different type of plugs available. Hot, Normal or Cold plugs (No.8,9,10 or 27,29,31). Decipher the tell tale signs from you plugs. Example = Engine running Lean, Proper or Rich (White burned, Brown burned or Dark Soot burned). A good experience mechanics will tell you what are the possible tunning (Air/Fuel Ratio) by looking at the used plugs.

 

I've been using the the OWS Iridium plugs for quite a while and I feel they're very good compare to the 2 other major competitor brand. Here is some guide for you to understand. Very very long. Hope it clear your doubts. (This article is taken from NGK's website):

 

SPARK PLUG BASICS:

The spark plug has two primary functions:

• Ignite air/fuel mixture
  
• Transfer heat from the combustion chamber

Spark plugs carry electrical energy and turn fuel into working energy. A sufficient amount of voltage must be supplied by the ignition system to spark across the spark plug's gap. This is called "Electrical Performance."

The temperature of the spark plug's firing end must be kept low enough to prevent pre-ignition, but high enough to prevent fouling. This is called "Thermal Performance", and is determined by the heat range selected.

It's important to remember spark plugs do not create heat, they only remove heat. The spark plug works as a heat exchanger

by pulling unwanted thermal energy away from the combustion chamber, and transferring the heat to the engine's cooling

system. The heat range is defined as a plug's ability to dissipate heat.

The rate of heat transfer is determined by:

• The insulator nose length Gas volume around the insulator nose
  
• The materials/construction of the center electrode and porcelain insulator

A spark plug's heat range has no relationship to the actual voltage transferred through the spark plug. Rather, the heat range is a measure of the spark plug's ability to remove heat from the combustion chamber. The heat range measurement is determined by several factors; the length of the ceramic center insulator nose and its' ability to absorb and transfer combustion heat, the material composition of the insulator and center electrode material.

Heat rating and heat flow path of NGK Spark Plugs

 

 

http://www.ngksparkplugs.com/tech_support/spark_plugs/image/chartheatratingflowpath-2.gif

 

 

The insulator nose length is the distance from the firing tip of the insulator to the point where insulator meets the metal shell. Since the insulator tip is the hottest part of the spark plug, the tip temperature is a primary factor in pre-ignition and fouling. Whether the spark plugs are fitted in a lawnmower, boat, or a race car, the spark plug tip temperature must remain between 500C-850°C. If the tip temperature is lower than 500°C, the insulator area surrounding the center electrode will not be hot enough to burn off carbon and combustion chamber deposits. These accumulated deposits can result in spark plug fouling leading to misfire. If the tip temperature is higher than 850°C the spark plug will overheat which may cause the ceramic around the center electrode to blister and the electrodes to melt. This may lead to pre-ignition/detonation and expensive engine damage. In identical spark plug types, the difference from one heat range to the next is the ability to remove approximately 70°C to 100°C from the combustion chamber. A projected style spark plug firing tip temperature is increased by 10°C to 20°C.

 

Tip Temperature and Firing End Appearance

http://www.ngksparkplugs.com/tech_support/spark_plugs/image/charttempfiringend.gif

 

 

 

The firing end appearance also depends on the spark plugs tip temperature. There are three basic diagnostic criteria for spark plugs: good, fouled and overheated. The borderline between the fouling and optimum operating regions (500&def;C) is called the spark plug self-cleaning temperature. The temperature at this point is where the accumulated carbon and combustion deposits are burned off.

Keep in mind the insulator nose length is a determining factor in the heat range of a spark plug, the longer the insulator nose, the less heat is absorbed, and the further the heat must travel into the cylinder head water jackets. This means the plug has a higher internal temperature, and is said to be a hot plug. A hot spark plug maintains a higher internal operating temperature to burn off oil and carbon deposits, and has no relationship to spark quality or intensity.

Conversely, a cold spark plug has a shorter insulator nose and absorbs more combustion chamber heat. This heat travels a shorter distance, and allows the plug to operate at a lower internal temperature. A colder heat range is necessary when the engine is modified for performance, subjected to heavy loads, or is run at a high rpm for a significant period of time. Colder spark plugs remove heat quicker, reducing the chance of pre-ignition/detonation. Failure to use a cooler heat range in a modified application can lead to spark plug failure and severe engine damage.

 

Below is a list of external influences on a spark plug's operating temperature. The following symptoms or conditions may have an effect on the actual temperature of the spark plug. The spark plug cannot create these conditions, but it must be able to cope with the levels of heat...if not, the performance will suffer and engine damage can occur.

Air/Fuel Mixtures seriously affect engine performance and spark plug operating temperatures.

• Rich air/fuel mixtures cause tip temperature to drop, causing fouling and poor driveability Lean air/fuel mixtures cause plug tip and cylinder temperature to increase, resulting in pre-ignition, detonation, and possibly serious spark plug and engine damage
  
• It is important to read spark plugs many times during the tuning process to achieve the optimum air/ fuel mixture

Higher Compression Ratios/Forced Induction will elevate spark plug tip and in-cylinder temperatures

• Compression can be increased by performing any one of the following modifications:
   
  a) reducing combustion chamber volume (i.e.: domed pistons, smaller chamber heads, mill ing heads, etc.)
   
  b) adding forced induction (Nitrous, Turbocharging or Supercharging)
   
  c) camshaft change
  
• As compression increases, a colder heat range plug, higher fuel octane, and careful attention to ignition timing and air/fuel ratios are necessary. Failure to select a colder spark plug can lead to spark plug/engine damage

Advancing Ignition Timing

• Advancing ignition timing by 10° causes tip temperature to increase by approx. 70°-100° C

Engine Speed and Load

• Increases in firing-end temperature are proportional to engine speed and load. When traveling at a consistent high rate of speed, or carrying/pushing very heavy loads, a colder heat range spark plug should be installed

Ambient Air Temperature

• As air temperature falls, air density/air volume becomes greater, resulting in leaner air/fuel mixtures. This creates higher cylinder pressures/temperatures and causes an increase in the spark plug's tip temperature. So, fuel delivery should be increased.
  
• As temperature increases, air density decreases, as does intake volume, fuel delivery should be decreased

Humidity

• As humidity increases, air intake volume decreases Result is lower combustion pressures and temperatures, causing a decrease in the spark plug's temperature and a reduction in available power.
  
• Air/fuel mixture should be leaner, depending upon ambient temperature.

Barometric Pressure/Altitude

• Also affects the spark plug's tip temperature The higher the altitude, the lower cylinder pressure becomes. As the cylinder temperature decreases, so does the plugs tip temperature Many mechanics attempt to "chase" tuning by changing spark plug heat ranges
  
• The real answer is to adjust air/fuel mixtures by rejetting in an effort to put more air back into the engine

Types of Abnormal Combustion

Pre-ignition

• Defined as: ignition of the air/fuel mixture before the pre-set ignition timing mark Caused by hot spots in the combustion chamber...can be caused
  (or amplified) by over advanced timing, too hot a spark plug, low octane fuel, lean air/fuel mixture, too high compression, or insufficient engine cooling A change to a higher octane fuel, a colder plug, richer fuel mixture,
  or lower compression may be in order You may also need to retard ignition timing, and check vehicle's cooling system
  
• Pre-ignition usually leads to detonation; pre-ignition an detonation are two separate events

Detonation

• The spark plug's worst enemy! (Besides fouling) Can break insulators or break off ground electrodes Pre-ignition most often leads to detonation Plug tip temperatures can spike to over 3000°F during the combustion process (in a racing engine) Most frequently caused by hot spots in the combustion chamber.
  Hot spots will allow the air/fuel mixture to pre-ignite. As the piston is being forced upward by mechanical action of the connecting rod, the pre-ignited explosion will try to force the piston downward. If the piston can't go up (because of the force of the premature explosion) and it can't go down (because of the upward mo-tion of the connecting rod), the piston will rattle from side to side. The resulting shock wave causes an audible pinging sound. This is detonation. Most of the damage than an engine sustains when "detonating" is from excessive heat
  
• The spark plug is damaged by both the elevated temperatures and the accompanying shock wave, or concussion

Misfires

• A spark plug is said to have misfired when enough voltage has not been delivered to light off all fuel present in the combustion chamber at the proper moment of the power stroke (a few degrees before top dead center) A spark plug can deliver a weak spark (or no spark at all) for a variety of reasons...defective coil, too much compression with incorrect
  plug gap, dry fouled or wet fouled spark plugs, insufficient ignition timing, etc. Slight misfires can cause a loss of performance for obvious reasons (if fuel is not lit, no energy is be-ing created)
  
• Severe misfires will cause poor fuel economy, poor driveability, and can lead to engine damage

Fouling

• Will occur when spark plug tip temperature is insufficient to burn off carbon, fuel, oil or other deposits Will cause spark to leach to metal shell...no spark across plug gap will cause a misfire Wet-fouled spark plugs must be changed...spark plugs will not fire Dry-fouled spark plugs can sometimes be cleaned by bringing engine up to operating temperature
  
• Before changing fouled spark plugs, be sure to eliminate root
  cause of fouling

[biting_point]

very very detailed..

[buttbutt8]

For norm ngk plug how long before we must change??? 10000km??

[JbAtRaCeR]

i think the gap can't be adjusted

 

Which gap?...the electrode and tip?...If that is,it can be adjusted,but you will need the tool and correct measurement(gap)..But nowdays no one wants to adjust. Why?..Its better to change new ones since they are cheap.You will also save time and money if those plugs suddenly fail..

[rykros]

very detailed abt spark plugs... any one noes if ngk-platinum is good??

[LordDevil]

very detailed abt spark plugs... any one noes if ngk-platinum is good??

g power is gd.

[buttbutt8]

For norm ngk plug how long before we must change??? 10000km??

 

sometimes it's not because ppl want to open a new thread, its just that old threads are sometimes too junky and messy and when u ask a qns, no one bothers to answer. Also, how to go thru 10 pages of infomation for one simple ans??

[mighty_mouse]

Have anyone tried using Splitfire spark plug before ???

Any comments to share.

Where can I get it and how much for 4 pcs?

Thanks

[warrior.c.o.n.p]

i think standard ngk spark plugs will b suitable 4 s4...

[Ghandhayutham]

Hey guys, about spark plugs, I riding a version S, one of the red "caps" cant go in all the way and i already tighten the spark plug maximum,(anymore I have to use alot alot alot of force...)

 

Anybody experience this b4 on their bikes? Anybody else's red cap's cannot go in all the way, as in the top is not flush with the hole you put the spark plug into...

[rykros]

din screw in the spark plug properly perhaps? open it up n check the thread... or wrong spark plug model?? dun juz see the model from the box, but on the plugs itself... hope tat helps...

[TheBeng]

din screw in the spark plug properly perhaps? open it up n check the thread... or wrong spark plug model?? dun juz see the model from the box, but on the plugs itself... hope tat helps...

 

bro, 3 of the plugs go in all the way, only one of the plugs its not going in all the way... all the same model... it was like this befoe I change the plugs too, just wondering if its something to worry about..

[rykros]

ohh okie... hmmm... im not sure abt tat bro.... never seen or heard sth lidat b4... but it doesnt cause any problems to u or the bike b4 rite? then it shldn't be a problem den... but b4 u changed the plugs, did u compare tat odd spark plug wif the rest?? anything different? if there is u better go do sth abt your spark plug seating fast... i recommend bikeworz at shun li industrial at bedok reservoir...

[TheBeng]

hrmm... I didnt notice... maybe Ill ride for a while then change again, this time I'll try to look out for any difference.. thanks bro...

[TheBeng]

I know whats the problem already. Theres cement glue down the hole where the spark plug goes, and becos of that the spark plug socket cannot get a good grip around the nut, so cannot go in all the way. I use hammer and knocked the socket in, then turn the socket, then knock, then turn now its sticking out a bit only... cant seem to get it in anymore.

 

@!$!@ shop sold me the bike with cement glue @$@ places.