As I posted on an earlier thread my Old Town Penobscot cracked this winter while sitting on the rack outside, it was properly supported yet still cracked about 8" vertically down the stern. Now this boat is used, well used it has skid plates on both ends to reinforce worn areas. My question is this is it logical to assume that since the royalex cracked with no forces applied to it, other than this godforsaken cold, is that a sign of the material becoming brittle and less pliable? Would you fix the crack and still rely on the boat for long distance remote trips? Or should I slap a flying moose sticker over the crack and relegate this craft to the ever growing collection of misfit boats that are designated for "Apple River use only"?

No way would I trash it. I have repaired and friends have repaired cold cracks on royalex canoes and used them. It will be fine. I would drill a hole at the end of the crack to stop progression asap. That thread or another recent thread outlined how to repair. Here's a pic of my Dagger Reflection:

Does it have wood gunnels? Cracked hulls on royalex canoes with wood gunnels stored in unheated areas are common. I bet the crack started at one of the screw locations.
What happens is that the two different materials contract/expand at different rates and the screw forces the crack. Wben storing such a canoe you should do one of two things. 1. Back the screws out of the gunnels for first 2 feet or so from each end. Screw them back in for the canoe season. 2. Widen the screw hole through the royalex so the screw doesn't touch the hull, it just connects the inwale and outwale but doesn't touch the hull.

Bannock: "Does it have wood gunnels? Cracked hulls on royalex canoes with wood gunnels stored in unheated areas are common. I bet the crack started at one of the screw locations.
What happens is that the two different materials contract/expand at different rates and the screw forces the crack. Wben storing such a canoe you should do one of two things. 1. Back the screws out of the gunnels for first 2 feet or so from each end. Screw them back in for the canoe season. 2. Widen the screw hole through the royalex so the screw doesn't touch the hull, it just connects the inwale and outwale but doesn't touch the hull."

Nope aluminum