So why don’t you tell us what is going on?
No one here is “wrong” because you know or don’t know what your talking about…
We have an opinion, we can’t diagnose a situation from here. Matter of fact where the hell are you? Try filling out your profile.
Around here my bike get soaking wet out in the barn just because of temperature swings and relative humidity conditions. It would help to know where you are at and what information makes you feel you don’t have a leak instead of asking why you have water intrusion.
Do know what causes condensation?
There is no need for ventilation or insulation in a unconditioned garage. There is no humidity to control and there is no temperature to control between the outside and inside of an unconditioned space. You can increase ventilation and insulate all you want and the problem is not going to go away.
As a matter of fact, it will more than likely make the situation even worse!