This is probably the first of many, many questions....:
Need to get new tires soon, and have discovered that I understand absolutly nothing about tires. The Haynes book states that the requiered tires are:
110/90-16 54H (Front)
120/90-16 63H (Rear)
What do these numbers/letters mean? Does this mean that there are only two tires that can fit on the bike? Do different companies matter? etc., etc., etc.....