[mfclark]

I have a 2000 Yamaha 115 it has been hard on plugs, even when new.
Any time I have idlingtrouble I replace plugs.
Get your plugs at auto parts store, about ten bucks for four.
Are you can get plugs at boat house for thurty bucks, same
plugs.
I run ring free in my 115 all the time, one oz. to 10 gal.
Ring free make by Yamaha.