Modern bottom brackets use a sealed bearing type construction that keeps water and debris locked out, so they seldom go wrong. Maintenance is impossible so they need replacing when they do wear out. Older style cup bottom brackets need to be re-greased every now and again, and occasionally will need to have their bearings replaced. There are a lot more teeth on the chainring cogs than those on the rear cassette, so need changing less regularly. Cranks usually a solid one piece construction so there is not much to go wrong.
Mountain bikers are in different world of repair entirely, one that borders on the comedic absurd. It includes large pumps designed to fill up big, fat tires that squish over things, and a medley of assorted slimes meant to be injected into tubes or tires. In that world, the number of days it takes you to fix your tire and return from the wilderness is a badge of courage—bonus points if you’re bleeding—and we’re guessing that’s not what you’re going for next time you set out for groceries.
Return: Bicycle and lock must be returned by the end of the loan period. User will be charged a $10.00/day late fee. After 10 business days user will be charged the full cost of the bicycle ($350) and rented equipment ($50 for lock and/or key). Failure to return bicycle, helmet and lock will subject user to legal liability of $400.00, as well as having student account placed on hold.
In spite of seat bags’ diminutive size, a lot of people really, really want them to accommodate more stuff. If that’s you, the medium and large seat bag (but not the small) have an extendable gill at the bottom, which you can see in the image up top. It zips open to create more room. With it unzipped, we could cram a wallet, keys, and phone inside the medium as well.
Nice, helpful, friendly. Central location. Good bikes (I had two over two days.) Bikes had a water bottle cage (some places don't do that!) Provided helmets if needed (I didn't) and a one-sided pannier containing a decently strong but not super-heavy cable lock and a patch kit. Only quibbles: 1) The owner helping me with getting my bikes seemed to 'drop me' for too long when someone else walked in. He should have said to them, after asking what they were in for, that 'I'll be with you as soon as I'm finished with this person.' So I had to wait a little longer than desired, but not bad. 2) On my second day, the pannier bag fell off and got lost after I stopped for lunch, which required locking up the bike somewhere, so I took the bag into restaurant and re-attached it using the two velcro straps on the rear rack. I've used many panniers before, thought I did it correctly. But apparently I did not. So I paid $55 (cost) to replace everything in bag and bag. In hindsight, I wished I'd put a bungee around bag straps to really secure it to bike. PROBABLY MY FAULT. 3) Bring a second lock to lock quick-release front wheel, as decently strong but not super-heavy cable lock isn't long enough for both wheels and frame.I had a second cable lock.

Next to everything else that might go wrong with a bicycle on an extended ride, a flat is a relatively minor issue that can be easily repaired trailside, if the right tools are at hand. If they aren’t, a quick fix can turn into a long walk. Well-prepared riders will perform a tune-up regularly and clean their bikes after every ride. For the less-diligent, a well-stocked repair kit will suffice.
Friction gear systems are a lot simpler to adjust, because the movement of the derailer cable can be modulated as you ride, every time you change the gear- they require less cycle maintenance. Modern index shifting systems are a little more complicated because each ‘click’ must release the exact right amount of cable to allow the derailer to move the correct distance to move the chain from one gear to another. Setting up and adjusting a derailer is not difficult and requires only basic tools, but there is a methodical procedure to follow.