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 P1,400 ($34.23) per sparkplug, compared to the "normal" price of P100 to P200 ($2-4) per sparkplug.
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