NGK spark plugs resistor type - BR10ES - long thread
NGK spark plugs resistor type - BR10ES - long thread


at the moment the spark jumps the gap it causes a high frequency burst of energy, this is known as RFI (radio frequency interference). this is why resistor spark plugs were introduces in the mid 1960's. placing a resistor within the spark plug suppresses the RFI. without resistor plugs in your moped you can experience static on your radio as well as interference with other sensitive electronic equipment such as iphones and laptops. some later model vehicles as well as newer super power moped engines must use resistor plugs for a proper "talkback" to the CDI

it is strongly recommended resistor spark plugs be used in any motor that has on-board computer systems to monitor or control engine performance. use of a non-resistor plug in certain applications can actually cause the engine to suffer undesirable side effects such as an erratic idle, high-rpm misfire, engine run-on, power drop off at certain rpm levels and abnormal combustion. resistor plugs are also recommended on any vehicle that has other on-board electronic systems such as, two-way radios, GPS systems, depth finders or whenever recommended by the manufacturer.

as a rule, performance is in no way impaired by resistor spark plugs. the only exception to this may be some models of high output CDI specify non-resistor  plugs.

these are long thread plugs like regular ES plugs

available in sizes - BR10ES

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