Originally Posted by Russ
That sort of makes sense, except...my bike was born as a mountain bike, with big, fat, knobby tires. If the wheels worked with those, I can't imagine that they wouldn't work with the 2.0 wide tires, which are narrower than the originals.
It's because it's highly likely your bike was delivered with rims that were too narrow in the first place.
It's just like the Sheldon Brown page says about MTB rim widths: years ago all MTB's came with rims that were MUCH wider than road rims, MTB's were around 40-50mm (like "cruiser" bikes have now!) and road rims were all ~25mm. But bike makers got into a marketing "weight" race, so they started putting narrower and narrower rims on MTB's (because the narrower rims were lighter) until now many MTB's come with rims that are just as narrow as road rims--even though the tires on typical MTB's are often twice as wide as road tires.
A lot of people with MTB's don't know this, because they've never rode anything but MTB's with too-narrow rims. Most MTB nowadays (even some susrprisingly expensive ones) come with rims that are WAY too narrow.
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It's not that you can't put fat tires onto narrow rims--you can.... -but when you air those fat tires down to 30 psi, the tires will get all squirmy in turns--and on wide rims they wouldn't do that. And using fat tires at low pressures is the whole reason for using fat tires.
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