blackattak
Expert
I just studded my sled last week & put in the new plugs. The dealer said my track was set a little tighter as he said it would stretch a bit more with studs added (has 750 miles/1240km on it prior to studding). I rode with another brand new attak (also an 07) all weekend & he consistently got better mileage. Also my top speed seemed to be down. Have you guys been seeing reduced mpg with these plugs (about 2mpg less this weekend than before)? Any feedback would be appreciated. I am thinking of putting the old plugs back in. 
