I turned a 2013 sportster superlow into a trike (DNA axle) rides great but the front tire is a concern. factory tire is a 120/70-18 and i want to replace it with a rear tire (more rubber, more miles) but I can't find any rears that size and I am unsure how far off original spec I can go, have found a 120/90-18 but I am unsure if it will fit my wheel (stock) rather not buy the tire then find out it will not fit. And I am finding it hard to find some decent fenders for it that are reasonable priced the ones that are available in the US are running $580-$700, that's ridiculous for a couple small pieces of fiberglass. Currently i'm using a trailer fender cut in half, it works, cost only about $40 but not real pretty. If anyone out there can school me on alternate tire sizes and tell me where I can get decent fenders at a reasonable price I'd appreciate it