It's common enough for one person to have more than one pen, a countable object.
If I needed to sign something, I need only one pen. I'd say the first.
If you asked to borrow a ben, I have none at all to give you, and I'd say the second.
2. I would say "any money" - a non-count noun.
Most people own only one bike for their personal use. If talking about myself, I'd use the first one.
If you owned a bike/scooter/etc. rental place, you would be expected to have multiple bikes. Let's say you had a big day; you might say to the late-arriving customer "I'm sorry, I don't have any bikes."
Student or Learner