Um, couch to 5k - and to be clear - 5 kilometers, in under 29 minutes is a good accomplishment after a few months of training. But 5 kilometers on a bike is super easy if you've improved your condition through running. That distance is probably too short for most cyclists here as it wouldn't be worth the effort getting into our pre-ride ritual/gear.

I wouldn't necessarily do a 30 miler on a first ride, but 10-15 miles is doable.