But they are relatively common and a range of brands, Kenda, Shwabbe (sp??) etc.
The Felt thick brick white walls are available from some place in Canada that sells low rider and chopper stuff but I can't remember the website, sorry. They were about $55 each :shock:
Short answer no. Long answer- Some of the older bikes may have odd tire/wheel combos. If the tire size currently has a decimal in the width portion, 24x1.75, you should be fine. If it is in fraction, then you need to source new rims.
Electra has some really cool tires that have an awesome profile. Fatty-O's rock. they have some other tires that are sweet as well. Felt has some called Thick Brick's that are cool.