Manual for my Softail says replace plugs every 10K miles. I've done that, but wonder just how long will those plugs really last (of course, with regular inspection/cleaning/re-gapping?

 

Good platinum plugs will get you way more than 10 k

 

I put 25,000 on the original plugs and could have got more but I had already bought the new ones ( 03 EG )

 

I replaced the original equipment plugs at about 18K...they had many miles left in them I am sure, but they are not expensive so what the heck.

Paul in Colorado

 

Going on 15000 miles on my stock plugs.

 

never went that far yet... but she's still running good on these now at 8k..
dealer always did them every 5k, Hummmmmmm.. wonder why???? ha...

part of the reason I am doing the services now.......

 

I change mine once a year...there cheap its just part of my start of the year service

 

My dealer replaces them every 5,000 miles too. at $1.75 each, cheap maintenance. If I were to go platinum, I might be tempted to run them forever.

 

I replaced mine at 10K, probably could of went another 20K, but why chance it.

 

Replace mine each time I change the oil (~ 3K miles)...they are inexpensive and easy to change.