Those looking to purchase an inexpensive used bicycle from a thrift store, yard sale, or flea market need to proceed with caution. While a $50 – $75 bicycle may seem like a bargain, you could be setting yourself up for a larger financial investment after you purchase it and, more concerning, possibly have an unsafe bicycle on your hands. However, there are a few simple strategies you can use when looking to purchase an inexpensive bicycle.

• SEARCH BICYCLE SHOPS AND CO-OPS FIRST – Various shops will display and sell used bicycles. If a shop has an experienced bike mechanic and is known to be reputable in your area, you can usually trust that used bicycles they are selling are fully functional and safe. Similar to “certified” used automobiles at a car lot, you know that it was fully inspected and repaired. Shops must have insurance to operate and cannot have unrepaired and unsafe bikes rolling out the front door. However, always ask them to make sure that a bike was fully serviced. The price may be more than what you may see at a thrift store or yard sale, but you can be confident that you have a fully operational and safe bicycle. Keep in mind that many shops simply do not sell used bikes as the profit margin is not enough to cover the costs to repair a used bicycle that’s only worth $50 – $125. For this reason, you should also explore options at community non-profit, “co-op” bicycle shops.
• INSPECT FOR ANY DAMAGED AND / OR MISSING PARTS – It is always a red flag to see a bicycle for sale with damaged and / or missing parts. It is best to steer clear of an obvious broken bike the seller may have. Walk away from anything with noticeable cracks or splits on the frame. Also, do not be convinced by a seller who states that a bike only needs a few small parts or that it will be an easy fix. In most cases, you will need specialty, bicycle repair tools, which can be pricey to purchase. Also, like cars, not all bicycle parts are the same or interchangeable between different types and brands. To illustrate some examples of damage, I went to a local thrift store and took a few photos of a bicycle that was for sale. I did not stage this; I actually went into a random thrift store and took photos of the first bicycle I saw. I’m sure the front desk employees thought it was a bit weird seeing a guy taking random photos of one of their bicycles, but I was on a mission!

In the above example, you can see that the left grip shifter is completely broken. The front derailleur (i.e., the mechanism that changes the chain on the front chainrings) is unable to operate because of this. The shifter, cable, and cable housing would have to be replaced. Parts and labor at a shop to repair just this breakage alone would be at least $40 for a generic grip shifter of this type. This alone is enough for a hard “No!”

Above you can see the obvious frayed cable that attaches to the front derailleur. The fraying is significant and is not safe. All of the strands should be combined into one tightly uniform cable with a crimped end cap. In this particular case, the shifter for this cable is completely broken so the cable would have to be replaced to properly operate the front derailleur. The price tag on this bicycle was $120, which is way too much for one that is damaged like this. For $120, along with a $40 fix (at least!), you could have purchased a brand-new, inexpensive bicycle at a retail store. And that’s just for the left shifter damage. There could be other issues you would not know without test riding the bike. Which leads me to my next point of advice.

• TEST RIDE THE BIKE – If there are no obvious damaged or missing parts that would make the bike unsafe, you should test ride the bike. This is particularly important if you are planning on purchasing it for yourself. If the seller will not allow it, take your business elsewhere. When testing a bike, please wear a helmet for your own safety. Obviously, you will not be able to test ride a youth bike given its size so you may simply consider buying a new one, or a used one from a reputable bicycle shop, if it is a meant as a gift. By testing a used bicycle, you can run through all of the gears, make sure the brakes are fully functional, and see if there are any issues with pedaling. If you do not test ride a bike, there are various problems that can be hidden to a visible inspection. One example on a bike I repaired is in the photo below.

A client purchased a Mongoose mountain bike for $40 at a yard sale and wanted me to tune it up. When I test rode the bike myself, the chain would continually slip under the load of pedaling when the chain was shifted into the fourth sprocket. By using a specialty gauge to confirm that the chain was still in good condition, I knew then that the sprocket itself was so worn that its teeth were not fully engaging the chain. The entire freewheel seen above had to be replaced. This repair alone ended up being more than the $40 he paid for the entire bike. Even experienced bicycle mechanics will not necessarily know if a chain will slip on sprockets by visual inspection alone. This is just one reason why it is important to test ride any used bike that you are considering buying.

• LOOK FOR MIXED MATCHED PARTS – While this may be slightly more challenging, look for components that do not seem appropriate for the bike they are on. I have seen used bikes that sellers threw old incompatible parts on to simply get rid of it. One crucial thing to look for is to see if the shifters match the rear sprockets and the front chainrings they are attached to. The click of each shifter should match the number of corresponding sprockets or chainrings. The right front shifter operates the rear gears, and the left front operates the front gears. The total gear combination is the “speed” of a bike (i.e., 10 speed, 12 speed, 18 speed, 21 speed, etc.) You multiply the number of front chainrings by the number of rear sprockets to determine the speed. For example, if there are three chainrings in the front and seven sprockets in the back, you have a 21-speed bicycle (i.e., 3 front chainrings x 7 rear sprockets = 21 speed). In this case, the right shifter should have seven click / shift options and the left shifter should have three click / shift options. These are typically marked on the shifters like illustrated in the photo below.

If you see a shifting system that does not match correctly, do not purchase the bike. I serviced a used bicycle that had a six-speed shifter attached to a rear freewheel with seven sprockets. With this incorrect shifter, the rider was not able to shift into all seven rear sprockets. This required the installation of a new 7-speed shifter along with a tune-up. Keep in mind that shifters come in various types of configurations (i.e., grip shifters, thumb trigger shifters, integrated road bike shifters with brake levers, etc.) with different speed combinations. Just make sure that everything matches up: the left shifter matches the front chainrings, and the right shifter matches the rear sprockets. Of special note, bicycles that only have one chainring in the front, like most beach-style bicycles, will not have a front shifter. This is completely normal. Additionally, older, vintage style bicycles that are 25+ years old may have “friction” shifters, which may not necessarily click for each gear shift like modern ones do. Unless you are a bicycle repair hobbyist, my recommendation is that it is best to stay away from purchasing vintage type bicycles given they may need a complete overhaul if not already completed by a bicycle shop.

While there are many intricacies with bicycle parts and how they work together, you do not have to be an experienced bicycle mechanic to rule out problematic used bicycles. Use common sense, and do your best to follow the advice I outlined above. As always, if it looks too good to be true, it probably is. That is not to say all used bicycle sellers are attempting to scam you. They may be simply selling a broken bicycle that they do not know how to fix, no longer want, and simply want it out of their garage. Just don’t become the new owner of that problem bike.

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