I camped at Letts Lake about 10 years ago... brought my bike with the intention of doing some exploring, but had a major mechanical that cut riding real short. However, I recall the area as being potentially
awesome for mt. biking. What I did ride was excellent (the trails on/around Miners Ridge)... these are primarily MX trails, so they have been carved out nicely (but you gotta be wary of the MXers!). I went on Memorial Day Weekend and the trails were moist and packed down nicely too... but I imagine they can get pretty loose & dusty (a la bottom of Toads Wild Ride) in the summer. The place has always been in the back of my mind, but with the Sierra so close to me, I haven't gone back for further exploration.
For your group swtballer, you probably want to stick to that Letts Lake Loop and maybe some Miner Ridge, like jibmaster said.
However.... I'm curious if anyone here has done the big rides I see on my
map. Done as a shuttle, they look like they could be sweet:
Ride 1: Letts Lake ---> Trail 15/Miner Ridge (5.5 mi) ---> Trail 20/North Trough (8.8 mi) or Trail 22/South Trough (6.2 mi) ---> Fire Road 25/Hornets Nest Ridge (1.9 mi) ---> Trail 28/Hornets Nest Grove (6.7 mi) ---> to Wolf Creek Staging Area (bottom of the mountain)... shuttle back up. That's 23+/- miles! There are also several off-shoots that look good on the map too (Trails 40, 31, 38 & 39)
Ride 2: Letts Lake ---> 15/Miner Ridge ---> 04/Fence Line (6.5 mi) ---> 06/Lady Bug (5.5 mi) ---> any combo of Trails 33/43/36/35 (2-3 mi) ---> 32/Letts Ridge (6.2 mi) ---> to Fouts Springs.... then up Fire Road 34/Potato Hill (3.9 mi)... and back to Letts Lake. That's over 30+/- miles (less if shuttled).
If the riding is good and not too torn up by MXers, I really think this place could be fun... probably best in the spring and fall. So... does anyone have beta? Jibmaster... your thoughts?