This article from Bike. Walk. Move. will help you through the process of buying a new-used bike:
Many new and veteran bicyclists opt for a used bike, whether it’s for economic reasons or a matter of personal taste. Not sure where to start and what to look for when buying used? Bike Walk Move asked Brent Fuqua, co-owner of Recovery Bike Shop in Northeast Minneapolis, for his best tips on buying a used bike this season.
When is the best time to shop for a used bike?
Any time is good, but spring is the best time. At Recovery Bike Shop, we build bikes all winter so that early in the spring we have a lot of bikes built and a greater selection. The further into the season we get, the greater the chance of our inventory being picked over, even though we find and build replacements as fast as we can. Expert tip: Start looking for a used bike early in the spring to get the best selection.
What questions should a potential buyer ask when looking for a used bike?
What’s been done to the bike to restore it? What repairs have been made? Has it been in a wreck? Other questions, such as where did they get it, and how long have they had it, can also be relevant. But the current state of repair that it is in – its current road-worthiness – is the most important factor. Expert tip: Ask the right questions before you buy.
What mechanical components should people assess when buying used?
Just about anything that moves should be examined or questioned. Derailleurs, brakes, cables and housing should be fresh and not corroded, and tires are also very important. Expert tip: Examine the components carefully before buying—make sure they’re new and/or rust-free.
What about cosmetic details? It comes with the territory that there may be some rust or scratches, but are there scenarios where people should think twice about buying if they see those things?
While a few “character” marks are usually to be expected on a used bike, excessive appearance of rust is never good because if you can see it on the outside, it’s likely on the inside, too. Paint missing around the joints in the front of the bike can also be a sign of it having been in a crash. Expert tip: Look for those cosmetic “warning signs” when searching for a used bike.
Is there a cut-off point for the age of a used bike?
Not really; some bikes were bought and never ridden. The above attention to wear and rust should cover the bases. However, one detail to remember about older bikes is that the older the bike, the heavier the steel used to build it, so there is a practicality and functionality issue that can come into play for the everyday rider. By the 70s and the 80s they were working with lighter-weight, stronger steel. Expert tip: Look for bikes built after the late 70s—they’ll be lighter and easier to haul around town.
Are there certain components you’d recommend replacing after buying a used bike, such as the tires or the seat?
If you are buying from an individual, anything that needs to be replaced can be a point of negotiation. It also depends on the amount of trouble you want to go through after the point of purchase. Things need to be replaced when they need to be replaced, so as a consumer, attention to those details will help you make the right decision. At our shops we automatically replace all of those components. Our bikes tend to run a little higher than the same model on Craigs List (typically 20-30 percent more), but the customer is buying a warranted bike and the peace of mind that they won’t have to deal with replacements right away. Some people that are selling bikes out of their garage are offering sort of an intermediate used bike buying experience, in that they fix the bikes up without a storefront. Expert tip: Negotiate everything if buying from an individual—whereas bike shops will typically offer warranties on used bikes.
So in the end there are a few different used bike buying experiences. You just have to pick which one is right for you, oftentimes based on how much tinkering you are willing to do, or how much money you want to spend after the point of purchase.