I will always advocating test riding a bike before buying it. That being said. I have bought a bike or two without riding it, but the cost was minimal and if you are knowledgeable enough, you can be pretty sure you'll at least fit on a bike and the rest can be altered - to a degree. (If you are spending mucho moolah - It is your money you can do what you want) But I'd rather test ride to be safe.