Thanks for these thoughts. Yes, I understand that I don't need to go to Cannondale for Avid Shorty brake parts. But my first encounter with a "problem" was trying to overhaul the rear wheel. THAT, as it turned out, was something specific to Cannondale in the year my T800 was built (2000? 2001?). I ended up buying a new wheel to "fix" the problem. The "gasket" I mentioned was a rubber seal to keep water out of the bearings. None of this could be had, which surprised (and frustrated) me. I assumed (I hope wrongly!) that, this winter, when I start overhauling the bottom bracket, head set, front hub, etc this winter, I would encounter similar problems as what I had encountered with the rear hub -- hence my post. bradtx, is that what you meant about what I want to do with the T800? Basically, I want to maintain it, ride it, cozy up to it as my buddy from many many great bike tours -- not just toss it out because it is ten years old. Besides, winters can get awfully long around here and a person can't fiddle ALL the time! And yes, this site has helped me out MANY times when I got in over my head! THANKS!
The rear hub on your Cannondale was likely a Cannondale rebranded hub. They had sealed cartridge bearings and there aren't replacements for the seals because cartridge bearings aren't meant to be serviced. You remove the bearing and install a new bearing when something goes wrong with the bearing. The cartridge bearing is a standard size that's available at many bike shops. If you can't find it at a bike shop, auto parts stores have them as do some hardware stores.
As for the rest of the bike, there is nothing proprietary about it. The bottom bracket is likely a Shimano (and not serviceable), the headset is probably a Cane Creek (which uses a sealed bearing that isn't serviceable) and the rest of the bike is likely Shimano. I'm working from memory here because my T800 has had
every thing replaced on it. The wheels are currently on my daughter's bike in Seattle and the rest of the parts have gone to other bikes or the co-op.
If you still have the original rear wheel, it's worth replacing the bearing. The hubs aren't Phil Wood smooth but they are still good hubs.