A giant crab like insect will eat the wooden rafters

I realize I've owned a motorcycle for years but have forgotten. It's near an aunt and uncle's house in front of where a neighbor's house and huge pile of dirt used to be. Almost all the dirt has been removed and there is a different and rundown house near by. My motorcycle has a self-diagnostic test, which I run. The cycle jumps onto the neighbor's porch. A man comes out to see what's going on. He's a motorcycle mechanic and tells me the sensors for the diagnostic tests are lose, so I have to get them hooked back up before I can find out if anything is wrong.

I get on the motorcycle and am joined my a friend - perhaps a cousin - who has a woman I had previously met with him. He asks if I want to come with them, I agree, thinking maybe I'll end up hooking up with the girl.

We ride the motorcycles to a house which is supposed to belong to a grandmother I never met. My cousins and other people are inside laying around playing games. I have a yo-yo but am not very good with it.

In the front-yard is an entrance to a underground sewage pipe or utility tunnel of some sort. I crawl into it and travel steeply down for several hundred yards. I come out at the bottom of a hill. I have a sack of old belongings which I throw into the rainwater sewer - old pictures, an incomplete Scrabble board, an old pillow. I feel like I'm polluting because I am.

I travel back up the hill, this time outside of the tunnel. There is a strip cleared for power lines and houses on either side. Many people are walking down the hill as I go up. Close to the top, I stop and greet a policeman who enters the utility tunnel with me. We walk back to the entrance I originally came in through - now there is a complicated and dangerous looking turn-style on the exit. I'm afraid it will crush my legs as I go through it, but it just pushes me out a little faster than I would have normally walked.

Back inside my grandmother's house, an aunt is smashing a giant crab like insect with her hands, exclaiming that it will eat the wooden rafters if it's not killed right away. It's body is three or four feet long and has eight legs which are more like tapeworms than legs. I know the scientific name of this creature and look it up in an encyclopedia.