I found this site recently so thought I'd finally get round to introducing myself.
My first mountain bike was a 21"(!) 15-speed Raleigh Mustang in the mid-late 80s, all 38lbs of it. I mainly rode around the North East with my brother on his Kona Fire Mountain (he's almost finished rebuilding it for commuting) and a friend with what I think was a GT Tequesta (dark metallic blue with rear U brake), both bikes a similar age to the Mustang, and we often met up with the Beamish Odd Sox club during the week.
In mid 1993 I bought a replacement, the KHS Montana Pro I'm still using today. The Rapidfire+ shifters were swapped for XT thumbies when I bought it, as I never liked shifting with buttons when trying out other people's bikes. The difference between them was amazing, not least the fact it was less than 2/3 the weight, and it gave me much more confidence to chuck it around than I ever had with the Mustang.
Thousands of miles were racked up on it around the North East, along with the odd holiday in Scotland, Wales and the French Alps where there were real mountains to play on, but once I got a job in East Anglia suddenly there was a shortage of places to ride, so I didn't really do much cycling for several years.
Then a few years ago I found out that there was a group of mountain bikers where I lived, so dug out the KHS and joined in. We have to make do with the fairly flat terrain around here, but manage to find enough to make it fun. We regularly get up to Thetford forest (unfortunately I was away for last month's Retrobike meet there), did the Marin Dusk Till Dawn in 2005, have been to Coed Y Brenin a couple of times, and will be charging round Afan this weekend.
They always seem surprised that I have no trouble keeping up on a bike without suspension when they all have hardtails or full suspension, but I guess growing up with decent hills to ride on helped a lot, and as I've always ridden without suspension its just normal to me.
The majority of the bike is original. Other than the usual bits wearing out, the Zoom 130 handlebar snapped a couple of years ago, and the wheels are new after the original rims wore too thin and started to break up.