"Mountain bike" means a lot of different things to different people, and many just buy one bike and accept its limitations or buy several bikes that do some things well at the expense of others. As a matter of personal budget, I don't have a lot of disposable income to spend on bicycle paraphernalia, and I would rather have one really nice bike than two or three mediocre bikes. More importantly, I have a fairly utilitarian perspective on my personal belongings. I strive to have as little as possible in my life cluttering my endeavors and I have to make a conscious effort to keep from being a packrat with bicycle gear.
The Juice allows me to build a rowdy trial ripper and a fast gravel grinder by just changing a few things between rides. Yes, it would be easier to own two bicycles, but it would cost a lot more and I would have to find storage for another bicycle. Here is what I have been riding on some non-technical trails and more technical trails than I intended.
I have a little over a month before the Texas Chainring Massacre, which I am riding 100k, and a few months to the 100k Castell Grind. I have ridden these events before on a cyclocross bike with 32, 35, and 42mm tires. Every time I participate in a gravel event on a CX bike, I start to think halfway through, "this would be a lot more fun on a bike with bigger tires!" Now is the time to test that theory.
I bought a Salsa Chromoto Grande fork used for a great deal. This fork has a tapered steerer tube and a 15mm thru axle just like my Reba suspension fork, but it's considerably lighter and more responsive.
The handlebar is a flat Answer bar that I got online for $10 and cut down to about 26", which is 4" narrower than the normal riser bars I use for trails. To make up for the narrower handlebar, I have a 100mm stem, 40mm longer than the 60mm stem I also use for trail riding. I finished the cockpit with some Ergon bars ends. I removed these ends from some Ergon wingy grips. I have no use for the flappy bits on Ergons, but the bar ends will clamp onto a handlebar on their own.
I have been experimenting with single-speed gear ratios for trail riding. 32/20 seems to work for any sort of chunk and climbing, but I have found that I am hack it 90% of the time with a 32/18 ratio as well and go faster on the flat areas. For gravel grinders though, I know that most of the terrain will be flat or at least in a straight line. For this reason, I bought a 38t Raceface front ring and I am experimenting with 18, 19 and 20 cogs on the rear. So far, 38/18 is working just fine. I set a personal record on a long climb with this setup just the other day.
Finally, nothing changes the ride of a bike like a change of tires. I have not ridden them yet, but I just acquired some 29x2.1 Schwalbe Thunder Burt tires. These tires are well under 600 grams each, unlike the 800+ gram trail tires I normally ride, and the minimal center tread should roll much faster on hardpack and gravel roads as a result.
