Jock Nights is a Tumblr blog with 131,000 followers, all of whom are looking for images, videos and GIFs of gay bros having a lot of fun in front of the camera. Note that while this site is hosted on a non-Tumblr URL, it is still able to be followed and enjoyed in the exact same fashion. It just uses the domain name Jock Nights instead.
Anyway, it regularly updates with new pieces of content that it both reblogs and sources from users that upload material directly to the admin. If you feel like you want to be enjoyed by others, you're encouraged to share your own material with the world. Note that Jock Nights is completely free to use and whether you use Tumblr or not, it's a great place to find that authentic type of X-rated content you want that's 100% amateur in nature.
So yeah, go ahead and check this place out - it has some of the best amateur porn Tumblr has to offer.