A lot of people are buying or being given older bikes and we wanted to share our tips for how to assess and test a second hand bike for safety and value:
1. Tyres: The most important part as they are the only thing between you and the road! Check for fine cracks (common on mountain bike tyres) splits and bulges. Needs some tread but road bikes often have little tread as smooth means less drag.
2. Tubes: If you test ride the bike you should tell if it has firm tyres and is holding air. if it is a child's bike then bear weight down on it and see if the tyres are firm. If when you get it home it does have a slow puncture it is best to replace the tube (cheap online) rather than repair. You can have the old repaired set as spares.
3. Brakes: Check for frayed cables (bits of wire sticking out) worn wobbly loose brake levers, wear on brake blocks and do they squeak? Hold the brake levers on (one at a time) and try and push the bike forward. Are both pads in contact with the wheel rim? Hydraulic brakes check for pad wear and fluid leaks/wetness.
4. Gears: Check they work - ideally by riding the bike, best up hill or under load. A lot of bikes have damage to the rear derailleur and the cassette (rear gears) can wear and jump the chain in high gears. This is caused by changing gear whilst still pedalling hard, which damages the gear teeth. Also check if the gear cables are frayed or rusty? or are the gear lever/selector rusty or loose.
5. Chain: Is the chain very rusty and stiff, or does it seem to have excessive wear? If it is slack might be a tired derailleur.
6. Wheels: Do they run true? or do they catch the brake blocks? Lift the bike off the ground and spin the wheel. Can be trued up but not an amateur job. Light alloy rims can dent badly if they hit a pot hole. Are the spokes rusty and/or corroded? Is there play in the axle? Push the rim back and forth across the bike to check for movement.
7. Frame: Many can have some rust and it is usually more cosmetic than anything. If it is rust free it may have been repainted or be alloy. A lot are now are alloy but can still corrode, otherwise usually no concerns here.
8. Forks: Check the forks at the wheel hubs are sound. The pivot/connection point to the frame needs to rotate easily but not too loose, turn side to side and check for stiffness. Put front brake on and push back and forth, is there movement in the forks? If it has suspension are the chrome tubes rust free and does the suspension work? Put brake on push down and it should spring back up. More expensive forks have compressed air valves to pump up the suspension.
9. Seat: Is it split near the front, where bare legs may catch it? Does the stem move/adjust height freely in the frame when the bolt or quick release is freed off?
10. Size: An adult or teenager needs to touch toes to the ground while seated as minimum each side to be safe. A child needs the ball of the foot each side to touch the ground. Make sure their fingers can curl round the brake and gear cables easily - but these should be adjustable to the reach (small screw head).
Many of the issues above can be dealt with by adjustments, oils, good maintenance or cheap replacement parts - like a new cable or brake pads. However some, like the tyres, derailleur or an entire wheel would be a lot more expensive to replace and may make the bike uneconomic to buy or repair.
This post was written for us by Re-Cycle - Local Bike Exchange and Repairs in South Hams