06 August, 2020

Out of the Shed and Onto the Road - Assessing Your Bike's Needs

by Igor

There's no doubt we're in the midst of a bike boom. Hopefully the increase in ridership and interest in the sport will help move a lot more money and infrastructure designs towards sustainable and safe riding around the US. And while new bikes are harder to find because they've simply been bought up, the used bike market is very healthy. And with that, we've seen maintenance and repair items absolutely flying off the shelves at VO HQ. So whether you're pulling your bike out of the shed, refurbishing a friend's bike, or just picking up a used ride, here's a guide you can refer to when evaluating what it needs.

Ocular pat-down of the bike

Is it covered in spider webs, is the the chain rusted, are the tires flat, are there any obviously missing parts? These are basic things you want to be looking for as the bike sits in front of you.


Look over the frame for any dings, dents, scratches, cracks, or bends. Look at the fork from the side and make sure it isn't bent from an impact or crash. Tubes very rarely break in the middle, so wipe off dust or grime at junction points to get a good view.

The wheels should be straight in the dropouts and inline with the middle of the frame and fork. If the wheel isn't straight relative to the frame, make sure it is straight in the dropouts and re-check. If it still isn't straight, either the frame or fork is bent or mis-aligned.

Condition of wheels

Pull the rim/tire lightly from side to side. You're looking for any play in the hub bearings. If the hub bearings are within tolerance, they shouldn't move. If you feel a click or klunk, the hubs need to be adjusted or re-built.

Spin the wheels and look at the rim in relation to the brake pads (for rim brakes) or fork blades/chainstay blades for disc brakes. The rims should be true without wobbles or bulges in the rim surface.

For rim brake bikes, look at the rim surface. The braking surface should be smooth and not overly concave. There is some tolerance, so consult the rim manufacturer for wear tolerance information. It is important to monitor your rim's wear because the rim bead could let go, causing a very dangerous situation. You'll need to rebuild the wheel with new rims if the rim surface is too concave. You can check by putting a straight edge against the rim and seeing how worn it is.

photo from https://www.cyclingabout.com/

Tires


Are the tires flat? Could need new tubes or rim tape - you won't know until un-mounting the tire and doing an inspection. Try inflating the tubes and seeing if they hold air. Tubes can lose air over time, so a flat tire can be due to a puncture or it could just be due to time.

Check the overall condition of the tires. Check for abrasions, dry rot, lumps, and debris. Be careful spinning the tires and placing your hand on it. I've gotten cut by an errant staple in the tread, when spinning a tire to inspect it.

Brakes

For rim brakes, check to see if the pads have equal distance to the rim. Squeeze the respective brake lever a couple times to make sure they haven't been knocked about and re-evaluate.

Here's a neat trick that our friend Tommy of Cutlass Velo sent over for aligning disc brake pads. Open up an image of a white screen on your cell phone, place it on the ground, and look at the pads in relation to the rotor. Refer to your brake's manufacturer recommendations regarding pad distance from rotor.

See how worn the brake pads are. That is, how much life in left in them. Pads that haven't been adjusted for wear often create a little ledge and will need to be replaced.

Dig your fingernail into the pad and to see what condition the pads are in. If it feels fairly pliable and soft they are good to be adjusted and re-used. If they feel rock hard, replace them. When in doubt, replace your brake pads.

Disc brakes are a bit harder to diagnose as they are harder to see within. A flashlight would be helpful to see within the caliper. If the bike has hydraulic brakes, check the junction points at the lever and brake caliper for any leaks. Here's a picture of a fresh vs worn disc brake pad.

photo from www.totalwomenscycling.com

Now give each brake lever a squeeze and try pushing the bike forward. Obviously if the brake works, it will be difficult to push the bike forward. If the bike has disc brakes and can be moved easily, then something is very wrong. The pads and rotors could be contaminated with grease or oil, or there is a leak in the hydraulic hosing, the cable/housing needs to be replaced, or the caliper needs to be re-built or replaced. Either way, it will need to be diagnosed when it's in the stand and disassembled.

While you're grabbing the brake levers, let's check the.......

Headset

Grab the front brake lever and rock the bike forwards and back. If the headset moves, it will need to be adjusted or rebuilt (depending on how it is made). Some disc brake pads move within the caliper (which is normal). You might need to turn the handlebars 90 degrees (wheel to the side) to isolate the headset from the brakes.

Drivetrain

First, check the chain for rust, stiff links, gunk, and correct length. You probably don't have a chain measuring tool at home, but if the rest of the drivetrain looks to be in decent shape, you can probably roll with it.

Inspect the crankset for shark-tooth teeth, missing or damaged teeth, and general condition of the crankarms. Scuffs from shoe rub are pretty normal, but wear shouldn't go beyond cosmetic. 


Grasp the crankarm and pull it back and forth to check for bottom bracket play. If you feel any knocking or looseness, the bottom bracket will likely need to be rebuilt or replaced. Depending on your mechanical comfort level, you can also spin the crankset backwards to confirm the spindle is straight and the spider is true. Spin the pedals, too to see their condition.

Let's look at the derailleurs. Check the front to make sure it isn't bent, worn through, or rusted. Push the cage in and out to make sure it moves.
For the rear derailleur, look at it from the back of the bike. It should be straight and not bent in either direction. If it is bent, the frame's hanger or the cage could be bent from an impact. Check the derailleur for scuffs, scratches, or damage. How are the jockey wheels? Gross? Shark-toothed?


Check both the front and rear derailleur for smooth operation. This is best done in a bike stand, but in a pinch you can hang the bike from a tree branch, a broomstick between two chairs, or some other creative perch. Turn the crank as you shift through the gears. The chain should move freely from one gear to the next. You'll also want to make sure the chain does not drop off the cassette or chainrings at the highest and lowest gears. 

Lastly, let's check the cassette or freewheel. Grab a rag or glove for this one. Grab the lowest gear with your index finger and thumb and move it towards and way from you. It's shouldn't move. If it moves, the cassette either needs to be tightened or the freehub body needs to be replaced or re-built.

Cables or housing

Housing should be in tact without corrosion or cracks. Check the cable ends for fraying or damaged strands. 


For hydraulic disc brakes, check the ends of the hydraulic hosing for leaks or kinks.

Handlebars

Check the handlebar tape and grips for any signs of impacts or scuffs that may signify a crash. Very old aluminum alloy bars should be replaced. Carbon bars that have been crashed should be replaced. 


Make sure they generally aren't bent and/or corroded.

For drop bars, peel back the hood covers a bit. If there is a lot of chalky powder, it is corrosion. Someone likely sweat a lot and the bars could be in really bad shape under the wrap. Bikes that live on the trainer generally fall prey to corrosion around the handlebars, headset, and fork due to perspiration and lack of fresh air. If I buy a used bike, I'm going to replace the handlebar tape/grips no matter what because people are gross. When you pull back the bar tape, you'll see what needs to be replaced.

Accessories

What accessories are mounted to the bike? Kickstands should deploy and retract with relative ease, and should not interfere with the operation of cranks. Fenders should be tight and free of debris. Bottle cages should be tight and not bent up (I've seen bottle cages get mangled because someone's pant leg got caught on it during riding). Bags should be secure and not hanging in the wheel.

While this list is by no-means complete, we hope this helps in a preliminary check of a bike you currently have or are looking to acquire. A well maintained bicycle is a good bicycle, no matter the brand or age.

6 comments:

Anonymous said...

"If I buy a used bike, I'm going to replace the handlebar tape/grips no matter what because people are gross." -- i'm getting this immortalized onto a sticker...or t-shirt!

Ford said...

And if your bike needs work you cannot tackle, expect your local bike shop to have a week or two service backlog. You're not the only one who's dragged an unused bike out of the shed. Two two of my local shops are three weeks out on repairs. They've also remarked jokingly about some of the basket-cased people want repaired.

Jon Spangler said...

I hate to be picky but I'm a writer/editor:

Yes, tubes can LOSE air over time, but tubes don't "loose" air:

"Are the tires flat? Could need new tubes or rim tape - you won't know until un-mounting the tire and doing an inspection. Try inflating the tubes and seeing if they hold air. Tubes can LOOSE air over time, so a flat tire can be due to a puncture or it could just be due to time."

Anonymous said...

> Hopefully the increase in ridership and interest in the sport

I hate seeing bicycle riding called a sport. For me it's transport not Tour de France.

Anonymous said...

Man has it been stressful working at the LBS...so many new riders and so little stock. We're running out of everything essential.

Anonymous said...

So what is the outlook for the supply chain to catch up and LBSs receiving new bikes?