Denso Iridium Plugs vs. NGK

A few weeks ago I decided to put a new set of plugs in just because the I hadn’t done it for three sets of tires.  When I looked around the garage I had two IW24s and two B8ES.  So I put them in, as all four were brand new.  It was evening, the shops were closed and the bike needed new plugs so I went with what I had.


Starting out in the morning I got stuck in traffic on River Road on my RG500.  Several miles of rolling through a tourist area at 5-25mph.  Hardly any stopping, so never got to take off and rev it a bit.  Just rolling along in heavy traffic at very low revs.

Guess what happened after being stuck at low speed/revs for several miles?  The two B8ES plugs fouled.  The IW24s were still working fine.

These were all brand new plugs with less than 25 miles on them before I started.  The NGKs fouled while the ND Iridiums kept on sparking.  At moments like that the few extra bucks for functional spark plugs sure seems worthwhile.  I’ll never put an NGK plug into a bike of mine again. 

I will always run ND plugs.

For more information on Denso Iridium spark plugs check out his link http://www.densoiridium.com/originofiridium.php