Active and family / Black Friday Bikes and scooters: The Department Guide
Black Friday Mountain Bikes: What to Check Before You Buy
Shopping for mountain bikes this Black Friday? What to check first: frame size, suspension, wheel size and brakes, with live listings to compare.
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Check frame size, suspension type, brakes and wheel size before you buy a mountain bike. A bike that fits and has good brakes is safer and more fun than one with extra features. On used bikes, ask about service history.
Frame size comes first
Mountain bike sizes are matched to rider height, and each maker publishes its own chart. A frame that is too big is hard to control on a steep descent, and one that is too small is tiring on a climb. When you are between sizes, think about the kind of riding you do: a smaller frame feels more playful, and a larger one feels more stable.
Hardtail or full suspension
| Type | What it means | Who it suits |
|---|---|---|
| Hardtail | Front suspension only | Beginners, cross-country, lower upkeep |
| Full suspension | Front and rear suspension | Rough trails, more comfort, more upkeep |
A hardtail is simpler and often lighter for the same quality of parts. A full suspension bike works best when the rear shock is good, and a poor shock can be worse than none.
Mountain Bikes to compare
Live listings, shown by eBay
Opens eBay in a new tab. Check condition, seller feedback and returns.
Brakes you can trust
Brakes matter more than almost anything else. Disc brakes give strong stopping in wet and muddy conditions. Check the pads and rotors on a used bike, and ask whether the brake fluid has been changed if the brakes are hydraulic.
Wheel size and tires
Wheel sizes are a matter of rider size and riding style. Larger wheels roll over bumps more easily, and smaller wheels feel nimble. Check that the tires suit your trails, with a knobby tread for loose ground and a smoother pattern for hardpack.
Gears and drivetrain
Look at the number of gears, the type of shifters and the condition of the chain and cassette. A worn drivetrain skips and needs replacement, which adds cost to a used bike. On any bike, check that the gears change smoothly.
What a used bike needs
Ask for clear photos of the frame, especially near the welds and the head tube, and look for cracks, dents and rust. Ask when the bike was last serviced and whether it has been in a crash. Check what you have to do before riding, such as fitting pedals or adjusting the brakes, and confirm the seller’s return policy.
Gear for the ride
Add a helmet, gloves and a basic repair kit to your shopping list.
More in the bikes and scooters department.
Frequently asked questions
What is the difference between a hardtail and a full suspension bike?
A hardtail has suspension at the front only. A full suspension bike also has a rear shock, which adds comfort on rough trails and more moving parts to maintain.
How do I know my frame size?
Use the maker's size chart, which is usually based on rider height. If you are between sizes, ask a bike shop.
Should I buy a mountain bike online?
You can, if you check the size chart, read the assembly notes and confirm the return terms. A bike shop can inspect the bike after delivery.
Found in the Black Friday Bikes and scooters: The Department Guide department.