Jan. 28: Chanoko Mountain Bike Duathlon #1The duathlons are $45 until race day when they rise to $55, while the mountain bike races are $40 (rising to $50 on race day). The Xterra event is $65 until race day when it becomes $75.
Jan. 29 : MTB Challenge #1 - Mountain Bike Racing
Feb. 18: Chanoko Mountain Bike Duathlon #2
Feb. 19 : MTB Challenge #2 - Mountain Bike Racing
March 11 : Chanoko Mountain Bike Duathlon #3
March 12: MTB Challenge #3 Mountain Bike Racing
April 1 : Granite Bay Duathlon
April 2 : REAL MTB Triathlon. Nissan XTERRA Points Race
All of the races listed above will be held at Granite Beach within Folsom Lake State Recreation Area in Granite Bay, California. Granite Bay is just east of Sacramento near Folsom and Roseville. TBF Racing has a map to the site here.
I've never competed in these races but I have heard some good things about them from other participants. I ride the trails that they'll be racing quite a bit and they make for a nice enduro style ride. I'll certainly be participating in the early season MTB Challenges, as I can almost see the course from across the lake.