Is it unsafe to put wheelchair tires on a bicycle?

Question

My son's vintage Bianchi bike takes 24 inch (24 x 1 1/4) tires and, as far as I can tell, that size is no longer in production. I'm thinking of trying a pair of wheelchair tires (Primo 24 x 1 3/8). How bad of an idea is this? Thanks! Gordon

Answer 1

http://sheldonbrown.com/tire-sizing.html

Width Considerations

Although you can use practically any tire/rim combination that shares the same bead seat diameter, it is unwise to use widely disparate sizes.

If you use a very narrow tire on a wide rim, you risk pinch flats and rim damage from road hazards.

If you use a very wide tire on a narrow rim, you risk sidewall or rim failure. This combination causes very sloppy handling at low speeds. Unfortunately, current mountain-bike fashion pushes the edge of this. In the interest of weight saving, most current mountain bikes have excessively narrow rims. Such narrow rims work very poorly with wide tires, unless the tires are overinflated...but that defeats the purpose of wide tires, and puts undue stress on the rim sidewalls.

The tire you mentioned should be OK.There is a graph on this page that explains why.

Yoy might want to try 26" wheels and a new set of brakes.

Answer 2

Wheelchair tires are designed to not mark floors and are usually gray. They are softer, break down faster in sunlight, and do not tolerate high speeds as well.