I pass out after i ride my bike?

Not normal: I would get this checked out by your physician asap. You need at least a cardiac evaluation.

Thats not good: Exertion can put a strain on the cardiovascular system, it's part of the idea behind what cardiologists do in terms of a "stress test". Individuals passing out with mild to moderate exertion should generall seek immediate medical attention and probably referral to a cardiologist. This should not be ignored.

Need evaluation: There are rare conditions that can cause people to have dangerous heart rhythms after they recover from vigorous exercise. In addition, structural heart disease can result in the same problem. Obtain evaluation, preferably with a heart rhythm specialist to assess this.