If its free, use it. I have noticed that since they started filling my tires with nitrogen, they wear out before they need more air. I wish tire makers would make a tire that last longer than 8000 K on the rear. I price one today at the local Harley dealer $290 plus mounting. A local bike repair and parts place locally sells Harley tires for $170 plus $10 mount and balance for carry in.

 

Air is already 78% or so Nitrogen. We used to use it in racing because it was inert and stable so we would get consistent tire pressure as we put heat in them. The Nitrogen molecules are supposedly bigger than air's and you get less seepage from the tire, but I was never able to confirm this either. I never noticed any difference in wear between a N2 filled tire or air filled. The moisture is much less in the N2 than air so over a long period of time so there's probably some modicum of less dry rot in the tire. If it's free why not I guess, only now you have to find a place with N2 to fill your tires.

 

More consent air pressure = better wear, All my cars and bike have it. Had 9500 miles on stock Street Glide tires with mostly 2 up riding with hardly any sign of wear with it.

 

I've actually wanted to try it, but none available locally without charging for it. My compressor sits right next to my bike, and I check the tires virtually on every ride. $00 is quite the motivator to stay with status quo.