I remember a friend told me that 40 (with the 3 stream crossings) was an easy trail he took his wife on. THe first time I rode it I couldn't believe it. It was a lot more challenging than I had anticipated. He later told me that it had washed out a lot more than when he did it back in the day. It took a few attempts, but I can now ride 40 all the way up without crashing (quite the feat for me.) In fact, it's one of my favorite trails now. I went one tooth lower on my front sprocket and it really helped with those trails.
You actually turned around on the toughest part of trail 40. It doesn't get tons easier for half a mile or so, but it doesn't get any harder than what you already rode. In fact, a mile later, on that same trail, is the best trail up AFC (in my opinion). It's a series of uphill turns with zero rocks in the trail, and the turns have little natural berms to them. It's so much fun.
If you want to join us on Thursday, you're welcome to. You won't be holding me back that's for sure. And you can learn a lot by watching the other good riders. If you're down to give it a shot, you're welcome to join us this Thursday. But we will definitely be taking trail 40 up from Tibble, that's almost always where we start.
Wait 'till you get to the ridge trail (152?) above that 40, heading towards forest lake. it makes 40 look like cake. I totally suck at that part of 152 trail, but I've gotten through it twice now. It gets a little better each time.
For an easier ride up American Fork Canyon, you can ride the fire road all the way up to pole line pass, and venture on to some of the singletrack from there. There are some fun places to explore up by silver lake flatts too. The dirt road will take you all the way up, overlooking major evan's.
I'd be happy to take you up there on a mellow trail sometime. I've got the noob run this saturday morning, but i'm usually available on saturday mornings.