I just changed my sparkplug today, and when I looked at the # on the plug, it was the wrong number. That plug was in there from the previous owner. The correct plug for a Scrambler 500 is BKR5ES and the old plug was BKR6ES. My question is...what's the difference between the two plugs? Is one a hotter burning plug or something? I was just curious if anyone could explain that for me.

Thanks.

 

Here is what your numbers and letters stand for on the BKR5ES.

B=thread diameter of 14mm
K=Hex size 5/8" / projected tip (ISO)
R=resistor type
5=Heat range
E=19mm thread reach
S=standard 2.5mm center electrode

The 6 would be a colder heat range. 2 being the hottest and 11 being the coldest.