My dad has a 87 softail custom sitting in our shed with rotten tires so for his birthday i want to buy him some new ones....any idea what size they are or where i can find a descent pair for pretty cheap...?

Read the size off of the side of the tire, don't buy cheap tires!! , Go with dunlops or another good name brand.

Metzler makes a great tire.

Go to motosport.com and get some metzlers! They are the best tire and are the price of a much cheaper tire from anywhere else. I know that it is easy to try and save money but i would never wanna send anyonethat i care about out on cheap tires. Otherwise dunlops are ok. Cannot go wrong with pair of metzlers from motosport.com tho.

Just my opinion. Hope it helps.
Josh

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2001 Donnie Smith softail frame, 80 inch evolution