A beginner's guide to knowing when it's time to get a bicycle tune up
An Inspection Checklist
So, does your bicycle need a tune up? Well…maybe. Here are a few questions to help you determine the answer to that question.
First of all, has your bike been sitting around unused for more than a year and a half? Is it covered with dirt or spider webs? Are the tires flat rather than just soft? Has it been abandoned for three years in your basement or storage room since you moved to town or had your children? If so, just come on down; we'll fix you up! End of discussion. That was easy.
However, for those of you who want to delve a little deeper, here's an extensive checklist and description of what to look for to determine the condition of your bike. This is the checklist we use at the shop when we inspect a bike. My only question is: Should I let y'all in on our trade secrets? Hmmm…..
Actually, this is very good information to have if you're interested in the mechanics of your bikes. Read on.
Inspection List Outline (details below)
Spin the Wheels.
Check:
Run Through the Gears
Other Components
So, your inspection will break down into three parts: the wheels, the transmission, and other components.
Part 1: The Wheels (and Brakes)
Spin the Wheels: You can inspect four things in about thirty seconds by spinning the wheels: the bearings, wheels, tires and tubes, and brakes. Here's what to look for.
Bearings: Do they need adjusting?
Grasp each wheel on top and give it a gentle shake from side to side. If you feel a little wiggle, the bearings are loose and need to be tightened. On the other hand, bearings can sometimes be too tight. This is not a common condition, but if they're too tight, it's usually because they were not adjusted properly when the bike was first assembled. You have to remove the wheel and turn the axle with your hand to feel an over-tight bearing. However, don't worry about that for our present purpose.
The Wheels: Are the wheels true? Do they need to be replaced? Are the spokes tight?
Spin the wheel and look between the brake pads. Using them as a reference point, you can see any wobble in the wheel that may be there. If it has a little wobble, but spins freely, it probably just needs minor truing. If the wheel won't spin at all, it either has a broken spoke that needs to be replaced, or the wheel is damaged to the point that it needs to be replaced. Next, squeeze some of the spokes and see if they feel inordinately loose. If so, they need to be tightened.
Side note: A wheel is a system. It must have all of its spokes in order to work properly. A missing spoke, over time, causes all the other spokes to loosen. If they get too loose, the wheel won't support the rider's weight and can collapse with you. That's why we check spoke tension on tune ups.
Tires and Tubes: Do they need replacing or just pumping up?
If a tire is absolutely flat, then the inner tube needs to be replaced. If the tire is soft, but still has some air in it, it just needs to be pumped up. It's normal for a tire to loose some air over a period of time, but not all of it, unless, of course, it's been sitting a long time. Now inspect the sidewalls. If they are scaly, extremely dry, (dry rotted) or have a lot of abrasions, the tire should be replaced. Tires blow out when they get dry rotted. We know. It's an ear ringing experience. Once in a while a tire will blow at night at the bike shop and set off the alarm! Tires blow very loudly!
Here's a tip. Avoid exposing your tires to prolonged sunlight. Tires, even new ones, deteriorate quickly if left in the sun for a long time. Also parking near furnaces or water heaters is said to deteriorate tires. Supposedly, the ozone omitted from these appliances causes them to deteriorate, but that theory may require some more research.
Brakes: Do the brakes need adjusting? Do the cables or pads need replacing?
Pull the brake levers. If they travel more than half way through the stroke before the brakes apply, they need adjusting. Next, examine the cables. Are they frayed or rusted? If so, they should be replaced. If the brakes feel sluggish when you pull the levers, but the cables look OK, then the cables probably just need lubricating. Next, look at the brake pads. Do they have obvious lips or edges worn into them? Are the slots in them (the wear indicators) shallow? Are the pads hard from age or do the brakes squeak badly when you apply your brakes? All of these conditions indicate that the brake pads need replacing.
Now you're halfway done with your inspection. In about thirty seconds, you've checked the wheel bearing adjustment, trueness, tires and tubes, and the brakes by simply spinning the wheels. What a mechanic!
Part 2: The Transmission
This is the larger part of you bike inspection. It entails evaluating the condition of a lot of parts and figuring out which ones need to be replaced and which ones don't. You'll be looking at the shifters and cables, chain, cassette, chainrings, derailleurs, and crank bearings. Because you will have to pedal the bike to check the gears, this part of the check over requires some sort of stand (or a helper) to get the rear wheel off the ground.
Run through the gears: Do they need adjusting? Do the cables or shifters need replacing? How much wear is on the transmission? Do any of these parts need to be replaced?
Gear Adjustment: Pedal the bike and shift the gears. Does the chain come off when shifting? Does the bike not shift into all the gears? Do you hear any rattles or rubs? If so, the gears need adjusting.
Shifters and Cables: Do the shifters click when you operate them? Do they feel sluggish or difficult to actuate? Like the brakes, if the shifters just feel sluggish, then the cables may only need lubricating. However, if the cables are frayed or rusted, they should be replaced. If the shifters don't click, they're likely gummed up from storage or old age and need to be replaced. However, with a little luck, a flush of WD-40 will revive them (which incidentally, is the only use for WD-40 on a bike. WD-40 is not for lubrication.)
Transmission Wear: It can be tricky to determine the amount of wear on a transmission, however, an inspection of the chain will clue you in to most of what you need to know.
Chain Stretch: We use a gauge to measure chain stretch (we recommend the Park CC-3), but chain stretch can be seen in extreme cases. Shift the chain onto the big chainring. Note how the chain engages the ring. If it hangs loosely at the bottom of the ring, or you can see light between the chain and the individual teeth on the ring, then the chain is way worn out and needs to be replaced. Chains need to be replaced because as they stretch, the shifting becomes sloppy and eventually the gears will slip, especially under load in the highest gear. We see high gear slip a lot on bikes where people like to ride in the hardest gear for a leg workout (a technique we discourage for several reasons, besides being hard on your bike, but how to effectively shift your bicycle's gears is another subject).
Furthermore, chains and sprockets, especially the rear ones, wear together. Thus, they should be replaced together. Running a new chain with and old cassette often results in a gear slip or exacerbates an existing one. (That's why we often mend a broken chain rather than replace it.)
However, there's a caveat. If you replace the chain early, when it is only halfway to two thirds worn out, you can keep using the original cassette. This preventive measure allows you to reuse the cassette and extend the life of this thirty five to eighty dollar component. Plan on replacing your chain every fifteen hundred miles if you want keep the same cassette. Expect to replace both your chain and cassette every three thousand miles. Your mileage may vary.
Chainrings have a longer life than chains and cassettes. They can be used with as many as three rounds of chains and cassettes (although that's a lot). You'll know to replace a chainring when the teeth get short or sharp, or if you see wide valleys between the teeth. Loose chain engagement can also indicate ring wear, but it may be difficult to discern how much wear is due to chain stretch and how much is due to chainring wear.
Check for worn derailleurs. To check the rear derailleur, wiggle that arm with the two pulleys on it. Does there seem to be excessive side to side play there? (Note that a little play is normal, even on a new derailleur.) On the front derailleur, wiggle the cage that the chain runs through. Do you feel excessive play there? Although it takes a while to wear out derailleurs, if you have a nice bike that you want to keep a long time, you may want to replace them when indicated. Worn out derailleur make for sloppy shifting, new ones restore crisp shifting.
Finally, check the crank bearings. Grasp the crank arms and wiggle them from side to side. Again, look for that tell-tale play that tells you the component needs attention.
You've now inspected your shifters and cables, chain, cassette, chainring, derailleurs and crank bearings for wear.
Note: The life of your transmission depends on your riding style, the riding conditions, and the extent of preventive maintenance you do on it. Your mileage may vary. But in any event, the cleaner you keep the transmission, the longer life it will have.
Part 3
Other components: Problems here are easily spotted.
Do a quick visual on the kickstand, pedals, handlebars, seat, grips (or tape), and any accessories you may have on your bike. Are any of these components missing, loose, or somehow damaged? Would you like to have fresh tape or grips? This stuff is pretty obvious.
Finally, check the headset. This term refers to the steering bearings that hold the front fork and facilitate steering. To check the headset, apply the front brake and rock the bike back and forth. You'll feel that familiar play in the front end of the bike if the headset needs adjusting. This adjustment affects the stability of the bike.
And that's It. You're Done!
That's a lot to read and digest, but hopefully the checklist will speed you through it. If you have questions after all that, call us. We're glad to help. We think this stuff is fun.
Happy Trails,
Mike