There are 2 differences with Marathons: the rubber is thicker (stretches less) and they have steel wire core beads, which don't stretch at all. All the Shwalbe 145psi tires use metal wire core beads, instead of just folded rubber like most other <=~100psi tires, so "stretching" the final bit of bead into place is harder. Add thicker rubber on top of that, and it gets that much harder.

I've used a large steel tire iron (spoon style motorcycle "travel size" Tire 'Arn), and zip ties, with good success. Technique + tools makes it much easier, but the no-stretch metal wire rim bead is the main difficulty, IMO.

Quote Originally Posted by funklab View Post
Can anyone explain why marathons (possibly other wheelchair tires, though I've been brand loyal for a long time) are so hard to get on? There doesn't seem to be a good reason. Changing bicycle tires is stupid easy and as far as I know they don't go rolling off of the rims all the time.

Are wheelchair rims inherently build differently than bicycle ones because manufacturers are worried about the lateral forces exerted on wheelchair tires whereas bicycle tires are theoretically never really experiencing a lateral force (at least so long as you're not skidding or crashing). That's the only thing I can think of, but it just doesn't feel like a realistic explanation.