That may have all changed recently after racing on both, one rigid and one with front suspension, at the Burn 24 Hour Challenge in Wilkesboro, NC a week back. It may seem like a no-brainer, but I have discovered that having one bike for short, fast XC races (around 2 hours) and one for long epic races (6, 12, 24 hour events and XXC races) is the way to go.
Well duh. I always have knowed that I wern't too smart. Now I've just done proved it to eberyone with this here post.
C'mon now, I should cut myself some slack. It wasn't as easy to figure out as it would seem. First of all, the two bikes have totally different personalities and ride characteristics. Trying to make one of them do something that it isn't good at doing took me a long time to figure out. For instance, the Niner's steep head angle makes it handle really quickly with the Niner steel fork installed. But throw on the trusty Rock Shox REBA and it feels quirky. The Rig on the other hand feels a tad sluggish on really tight, twisty singletrack. But for epic races, she is stable and tracks great with the REBA up front.
The Rig also has a riser bar, while the Niner sports a flat bar with a riser-type sweep. Both feel natural on the respective bikes. Toss some bar ends on either and it throws the "feel" way off. So from now on the bar ends stay in the parts bin.
The Rig (aka The Purple People Eater) will be my XXC bike, and the Niner (Mable) you will see on short, fast and smooth XC courses. So, I think the days of constant tweaking and changing and tweaking again may be over. But, if I were you, I wouldn't believe a word I say about that. I've been know to change my mind a time or two about bike set-up.