Vintage Dirt Bike Q & A

I used to have and ride dirt in my day, but then a wife and kids got in the way and the dirt was done. Now I have grandkids, the oldest just turned 11. He got a KX65 for his birthday and I had been commissioned to drag him out to ride it. This was kinda fun the first two or three times, then it was load, unload, sit and watch, load, unload, beer...
So, I started looking. Ebay was one place I watched and I found this 82 CR250 that was local and the bid was low, grabbing my interest. Watching the auction progress towards the ending moments, 2 guys battled back and fourth running my price up $20 at a whack. With 30 seconds left I threw caution to the wind and placed my max bid, and won! It was Friday and I emailed the seller asking him to call me. Within an hour he called and agreed that I could pick the bike up that evening so, loaded the wife and grandkid into the truck and headed south. When I got there he had the bike out and ready. Hopping on it started first kick and I took a 1/4 mile ride down his dirt road and back. Then he showed me the rest of what I had bought with the complete bike.
1 extra parts bike missing front forks, bars and fender!
1 extra engine besides the one on the parts bike.
1 gear case with transmission gears intact
1 set of extra transmission gears
1 new clutch
1 extra used clutch
5 extra cylinders with heads.
new pistons, rods, rings, etc.
I've done little to the bike besides ride it in the 2 weeks since I bought it. My grandson and I are having a blast tearing up the trails near our house. I was looking for someplace that supports vintage bikes like this and came across this forum. I hope to learn alot about my new/old bike and maybe even contribute in some small way. Thanks for being here!!
Dave