My first real mountain bike was a chromoly Specialized Stumpjumper from REI. It had a custom Rock Shox air/oil front suspension fork and a Shimano LX groupo. I gradually customized it with a Gorilla brake booster and Bear Trap pedals amongst other unnecessary upgrades. It was a great starter bike.
I tore it apart and put it back together again, stripping bolts along the way. I borrowed Sloane's New Bicycle Maintenance Manual from the library and absorbed as much as I could. It's how I got into becoming a bicycle mechanic.
My dad snapped this shot of me, just as we descended the Dog River trail near Mt. Hood. It was one of my first group rides with my local shop, Custom Bicycles, who eventually became my first employer. I was sporting my dad's old Nike running shoes because they were so spongy and gripped so well with my pedals. I also had on a pair of protective shop glasses. Talk about performance on a budget.