27-02-15, 08:05 PM
The resistors in the NGK one are wire wound whereas the Yamaha OEM ones are Carbon.
The carbon ones are cheaper to manufacture, but their resistance values can vary by 20%.
The wire wound ones are more accurate, normally within 5%.
The carbon type age badly and the resistance rises as they get older and coupled with corrosion it plays havoc with the spark, causing misfires, poor starting and all sorts of other issues
Be sure to clean the brass piece deep in the cap also. I usually spray the inside of the cap with WD40 before reassembly
If you put back the original caps with the NGK resistors pack the top of the cap with vaseline before replacing the rubber boot, no more water ingress.
The carbon ones are cheaper to manufacture, but their resistance values can vary by 20%.
The wire wound ones are more accurate, normally within 5%.
The carbon type age badly and the resistance rises as they get older and coupled with corrosion it plays havoc with the spark, causing misfires, poor starting and all sorts of other issues
Be sure to clean the brass piece deep in the cap also. I usually spray the inside of the cap with WD40 before reassembly
If you put back the original caps with the NGK resistors pack the top of the cap with vaseline before replacing the rubber boot, no more water ingress.