Any of you guys try iridium plugs in an old evo? If so, howd it work out for ya. I read somewhere it takes 500 less volts to fire them and the dam things almost last forever.A local guy that builds racing quads told me that soon all the factory HD's will come through with them. He also mentioned a longer burn and more efficient combustion. I think i might try a set in my evo. Thanks in advance for any info you might have on this subject

 

I use them in my 93 Fatboy. I like them. I get them thru Amsoil. NGK's Idle I think is a little better. Starts up a little easier too. A little spendy but I think they are worth it.

 

I put them in both our bikes before Sturgis this year. Work well. It's hard to say a spark plug made a difference with the butt dyno, unless what you were replacing was completely shot. Then it's hard to say one new plug is better than another, but the Iridiums are supposed to last a lot longer, jump higher, run faster, fart louder, etc. I use them in my Esprit Turbo as well. They are supposed to fire better under boost conditions, so most turbo people are running them.

I used NGK Iridium 2115 / BPR5EIX-11 on my bike and gapped them at 042. Cost isn't too bad, as you only have to buy 2 of them.

 

I also run the NGKs and love them. When I first put them in I had a long-time HD rider tell me to get them out and put in a set of HD plugs, I was crazy for putting those Jap plugs in there. Well, I listened and switched and hated it. Much harder to start and really didn't run as well in my opinion. I switched back and don't plan on looking back. So, in my humble opinion, they are a great plug and worth every penny.

 

I have them in my 95 and they have worked great. I don't know if they made the bike run any better because at the time I put them in I rejetted the carb because when I got it the jetting was off so most of the improvement in running I figured was from the carb being correct. I have had them for almost two years now and no problems.

 

I have them on my 85 superglide. They run well but I have found they foul a little easier than conventional plugs.

If I leave my choke open a little too long (S&S E) they foul quickly whereas conventional plugs are much more forgiving.

 

In my opinion,the HD "Champion" plugs suck!

"Champion" didn't work in my muscle cars,and they don't work on my bike.

I've been running Autolite 65's for the last ten years with no issues but might try a set of NGK's.......they sure worked well in my moto-cross days.

 

Over the years there have been so many new ideas (tried most of them)on how best to fire the mix,it does make a person hesitant.

 

If you’re looking for the best spark plugs for Harley Davidson EVO, we’d recommend NGK iridium plugs. They’re designed to increase horsepower and they’re some of the most durable plugs on the market.

 

This old post prompted me to install NGKs in my Fatboy back in 2009. The same plugs are still running strong….. 13 years and 50 k later.
I removed them last summer to install an accessory…. glad I used that high temp anti seize way back then too. Plugs looked fine and I put some more anti seize on before reinstalling. Rode the Fatboy yesterday, still love that scooter!