Be careful not to find yourself 7 miles away from home on your bike and too tired to keep on cycling.
If that means arranging with a friend to pick you up in their car if you have to bail out, or picking a circular route that never takes you that far from home, or any other way of handling the contingency. Going "but suppose I fail!" and not trying is an even worse piece of wormtonguing than the one fubarobfusco is addressing.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.