On 3/28/2020 2:51 PM, AMuzi wrote:
On 3/28/2020 1:22 PM, sms wrote:
Yesterday I got a call from a friend looking to borrow a
bicycle for her de-facto husband who's in his seventies.
Their gym is closed due to Covid-19 and they wanted to do
some riding. She brought her bicycle to a shop to get new
tires (before asking me!) and no doubt spent $100+ on tires.

I had a spare "comfort bike" that someone had given me a
couple of years ago https://www.amazon.com/dp/B002FKV2R8
in a shed.

I hadn't ever used it and of course the tires were flat. I
tried to inflate the tires. The front tube would not take
any air. The rear tire would not seat easily, it looked like
it was too big for the rim. I thought I had it seated and
inflated the tube and it seemed okay but then a few minutes
later the tire blew off the rim and the tube exploded.

Is it normal for unused tires to deform and enlarge when
left unused for a couple of years?

The tires were some sort of cheap Kenda tire but they looked
brand new; the person that gave me the bicycle because she
was moving away had obviously almost never ridden it. The
rear wheel was horribly out of true but it probably came
that way (she bought the bicycle at Sports Authority).

I had some Schwalbe tires, and the tubes were full of slime
(which may have wrecked the valve of the front tireÂ* so I
discarded them and put on the Schwalbe tires and Schwalbe
tubes.


Yes, tires can take a crease from sitting flat.

I haven't had that problem, but I wonder if careful warming with a heat
gun or hair dryer could relax any creases?

Best practice is to remove the tire/tube, inspect beads, inspect rim
liner to ensure it's the right one and centered. Wax or otherwise wet
(auto tire seating goop) the rim, mount tire, air halfway and spin the
wheel to ensure bead lip is visible evenly all around. Pull tire up
where it's low then air fully.
Kenda are quality tires, very uniform. Your problem likely lies elsewhere.

I recall resurrecting an old three speed Huffy that was given to a
friend to use as a shopping bike. I put new 26" tires on but had great
trouble getting the beads to seat exactly right. It really did seem like
the ancient steel rims were a bit oversized. Or perhaps the tires were
undersized. I don't recall the brand, though.

IIRC, I finally settled for the register line being a bit deep into the
rim at one spot. The bike rode OK. Not perfectly smooth, but OK for the
mile to the grocery.

--
- Frank Krygowski