In addition to the Rema patches, put a new tire tube in your kit. The best method for dealing with a flat roadside is to swap out the tube and save the task of patching for later. If you’re not sure what size your tires are, it’s printed on the sidewall of the tire. This inner-tube buying guide has some photos of where to look. What brand is almost irrelevant as many tubes get manufactured in the same place, so whatever your local shop has behind the counter for under $10 will work fine. The only reason to spend more would be to save weight.
Yes, bicycle shops generally provide repair services. A typical list of offered services includes regular service/adjustment (including safety check; and brake, drivetrain, and tire inspection); premium, and annual service, which is a more extensive tune-up. More specific repairs include drivetrain tune-up, brake system tune-up, flat tire fixes, brake repairs, cleaning and touching up the bike frame.
If you’re going to use the chain whip you just made, you’ll also need a way to get that cassette off. A lockring remover is a must-have; unless you use one of the shady removal methods I’ve seen on the internet—which I wouldn’t necessarily recommend unless you don’t care much about the condition of the wheel after you use them. I recommend Park Tool’s iterations here that cost about $6, but you’ll need to buy the specific one for your brand/type of cassette. (By the way, I’m assuming you already have an adjustable wrench laying around somewhere to use with this tool. If you don’t, well, you’ll need one of those too.)
Be organized. “I like having everything be really small and super organized. I put all of my tools in CamelBak’s Tool Roll. It’s got little compartments, and I can separate tire changing stuff in one place, stuff like extra pedal cleats or an extra derailleur hanger in another, and it all rolls up into this tidy pouch. If I do have a repair, I can pull that one thing out and lay it out on the ground and it’s easy to work.”
On a very sunny Saturday I had a rear spoke break - you can imagine that no shop was willing to promise a quick repair! I was so fortunate to find this shop and will come back - Andy not only told me to come down and he'd get it fixed, he had his assistant work with another couple while he measured, cut to the right size, installed and trued the wheel while I waited! It was awesome, and the whole place had a great feel and good people. Best of all he charged a very fair $20 for all that work - I would have paid a premium for the quick service! After experiencing lots of attitude at other shops and poor service, this was a real find. I hope you will check them out, they have a great selection of bikes and accessories too! Good people and good craftsmanship should be rewarded.
First, carbon. You already know you don’t need it for your casual weekend pursuits, because you’re not counting ounces the way a professional road racer would. But to quote an article from Velonews, “Remember that professional athletes operate in an entirely different environment than the rest of us. They are all very close to each other in terms of fitness, and they are also all very close to being the absolute best a human being can be. In short, you’re much better off upgrading your legs and dropping body fat through proper training and diet.”
There are two major types of headset- older, threaded headsets that have a quill that drops into the stem of the fork creating an interference connection, and newer threadless headsets that the stem is bolted and clamped on to. Flat handle bars are preferred by off road cyclists who can ride in a more upright postion whilst still having the controls at their fingertips, whereas drop handlebars offer more cycling positions and are favoured by road cyclists who typically spend more time in the saddle. The controls attached to the different styles of bar are operated and maintained in different ways.