Iridium Spark Plug

Since changing the spark plug is more than a 5 minute job on the WR250R I'm thinking of installing an iridium plug (CR9EIX) to extend the replacement interval. I've used them on prior bikes with good results but I don't see any mention of them in searching this forum.
Anybody have experience with them on this bike?

I put one in at about 1k. miles, no problems now at 9K.

miniceptor86 wrote:

I put one in at about 1k. miles, no problems now at 9K.

That's encouraging. My experience on the 650 V-Strom has been good, with over 50k before changing. I hope the WR will be similar, although I realize they'll be more wear given the higher average rpm.

I have also been running the NGK CR9EIX with good results for approx 10,000klm's.....

Although not that full distance on the one plug, as i fitted the 1st Iridium from new at approx 1,500 klm's. Then at approx 8,500 klm's i fitted the 290 BB kit, at which time i also fitted another new CR9EIX. I have now since covered another 3,000 klm's on the 2nd plug, so all good at this stage.

As for the Yamaha recommended plug replacement interval of 20,000 klm's, well i reckon that's a pretty big ask on a "soft metal" plug in this HI-PO little single. Proberly go that distance ok on a "normal use" stock standard bike, but with a fuel programmer, i'd say 1/2 that interval to retain MAX spark plug & ignition system performance. Most owners tend to set their programmers way too rich, placebo effect lol, and i very much suspect that this is a major contributing factor to the "known" issue of premature plug fouling / failure. ( Even when the plug "looks" ok ).

This being said, even with the Iridium plug fitted to my bike, i still plan on inspecting the plug every 10,000 klm's. For my current use that distance would occur approx every 18 months. It's a bit fiddley with the tank & fairing R&R, but it's not a hard job, so i'm happy to cover this as "preventive maintainence".

The single most important factor to keep in mind with the Iridium plug is that although it has the very hard wearing Iridium needle tip, it only runs with a single earth electrode. So this could very well be where the 1st signs of wear occurs.

In any case, from my direct experience i can recommend the CR9EIX as being very worthwhile for the WRR/X. There is some mention of the Iridium plug giving a negative performance effect on this bike, but not in my case. ( Report in a thread on this forum that the Iridium plug "hurts" low rpm torque & power, worse when cold ? )....

Maybe when/if you go back-to-back with the 2 different plugs you can report back with your results as well.

Cheers.

I too installed the plug mentioned and have had great results including the 290 kit. Berwyn

I'm about to fit an iridium plug to my bike, too. Not in the hope of gaining power, but just to reduce low-speed fouling and make it easier on the electrical system.

I'd be very interested in hearing how others go, as my bike won't be used seriously until later in the year.

I put one in the beginning of this season and developed a code 19 and the bike would cut out on me often. The same issue was brought to light somewhere else here. I put a regular plug back in recently and have not had any problems.

Going with the same brand and temp plug in copper/platinum/iridium will have not effect at all on performance. If someone is having issues odds are you have a defective plug, which is possible.

The only thing iridium gets you is longer life when counting the number of sparks. If you are going to foul out a plug iridium will not help, a hotter plug might.

When I replaced my fuel tank I put an iridium in, it was cheap and I am lazy, now I will never have to do it again.

Iv had a Brisk plug in for over 6k miles with no problems !

I know that this is a 10 year old thread but I had just replaced my 10,500 mile OEM spark plug with a new NGK EIX Iridium spark plug. I had gapped it to .026.

The gaps that were in the twin tipped NGK spark plug were both over .030 so over the 10,500 miles since new, the gap had grown past the .024 to .028 that Yamaha specifies.

I like to think that the motor is both starting easier and running better with the new plug installed though the engine has been running great since day one.