Originally Posted by
Tandem Tom
Not sure that is completely accurate. The gravel riding guys we servive don't typically carry the weight and amount of gear for the extended period of week after week of riding. So the durability issue of the tire is a key factor.
I've been 210 to 225# over the last few years. My 43mm GK SS tires carried me as well as my 23# gravel bike perfectly fine for years.
There is 0 meaningful difference between me on that gravel bike and a 175# person with a 30# traditional touring bike and 20# of gear and food. Given the variance in total system weights and it being a total unknown for each of the people that have responded to you, just trust that GK tires competently and easily handle way more than 250# of weight and tires don't care if the weight is on the rider or bike.
Also, tires don't care that they get ridden every day- be it road, gravel, or touring tires.
You mention tire durability. Do you think purpose build gravel tires by default lack durability? The Marathon Supreme tires you plan to replace are not inherently more durable than any number of commonly popular quality gravel tires.
As an experienced touring cyclist and shop employee, I am sure none of this is new.