Common Mistakes That Can Be Avoided For The Do It Yourself Mechanic
1. Don't use screwdrivers to take off and put on tires.
This seems like a good idea, but the sharp edges of screwdrivers are made to grip screws, and these edges will cut into your inner tube, separate your tire from it's bead and scratch your rims.
You can save money using a screwdriver (around dollar from the hardware store / tire levers are about $3 for three of them) , but the risk of messing up a $4 innner tube and spending at least $12 for the replacement tire is too great. For more tire changing information, go to "How to Fix a Flat"
2. Don't turn your bike upside down without protecting your seat and handlebars.
Scratching your handle bars, ripping your grips, or tearing your seat is one of the unforeseen outcomes of fixing your bike while it is upside-down. It is much easier to work on a bike right side up. For quick adjustments, have someone hold up your bike. If you are doing more involved work you can set up two hooks in the ceiling and connect them with rope to your seat and handle bars. If you find yourself fixing your bike a lot (you ride off road) you can invest in a repair stand (repair stands start at $100).
If you do put your bike upside-down put the seat and handle bars on something soft (a towel or a rug).
3. Don't slap any old chain lube on you bike.
A common mistake is to put fresh lube over old gummy and dirt filled chain lube. If your chain has a tar like film on it it is a good idea to remove your chain and flush it with solvent (use the solvent according to directions). To avoid your chain from becoming gummy, wipe off the excess lube with a paper towel after applying fresh lubricant. This will also displace some of the dirt that has accumulated on your chain since the last time that you put lube on it.
Other chain lube mistakes are using WD-40 (WD-40 displaces water but it is not really a lubricant), using axle grease (catches flies on your chain but does not penetrate to where it is needed), or using no lubrication at all (noisy and makes your chain all brown and crusty)
For more info on chain lubrication see the past "Wrench Connections" : "How to Lube Your Chain" and "A Basic Guide to Chain Lubrication".
4. Don't pack too much grease into your hubs, headset, bottom bracket or pedals.
If you put too much grease into a bearing surface, the extra grease will be pushed out at the seals when you ride. This grease will collect dirt and contaminate the bearings. You can wipe off the excess grease but the chances of pushing dirt into the bearing races is high.
If you put a 1/16 inch layer on the race, insert the bearings and then apply another layer that fills in the space between the bearings , this should be enough for lubrication and no excess should attract dirt.
5. Don't use your quick release skewers like a wing nut.
The proper use of quick releases insures that your wheels stay on your bike when riding. The way to fasten your wheels using a quick release is to open and close the quick release with your right hand while gradually tightening the adjusting nut (located on the opposite side of the hub) with your left hand in the clockwise direction. Continue until you feel resistance with your hand at the point where the lever is parallel to the hub. Grip the fork with your fingers and use the palm of your hand to close the lever with as much strength as possible. When closed, the lever must be in the "Close" position (the side of the lever with the inscription "Close" must be facing away from the wheel and the lever should be parallel to the fork leg).
If you have any confusion about this process call or email us at Cycle Path (advice is free)
6. Don't substitute a right pedal for a left pedal.
As you sit on your bike right pedals screw into crank arms clockwise and left pedals (as you sit on your bike) screw in counter clockwise. How does one tell if you have a left pedal or a right pedal? Pedals are marked with an "R" and an "L" on the spindle. Always start threading pedals on by hand. If you have any resistance, double check that you are using the correct pedal on the correct side (use extra caution if your bike is upside down). If you cross thread a pedal you will, more than likely, need to get a new crank arm and possibly a new set of pedals.
Bottom brackets on English and French bikes (not Swiss or Italian) also use reversed threads on the fixed cup (right side) and you should exercise even more caution when assembling these. Fixing a cross threaded bottom bracket shell is very expensive.
Why do they use reverse threads? It is to prevent pedals and bottom brackets from working themselves loose due to the rotating friction when you pedal forward.
7. Don't lube your chain so that overflow can find its way onto your rims.
If you get lube on your rims, when you go to use your brakes, you will find that they will not stop very well. Remove as much lube as possible with a paper towel. If you still have less than adequate braking power, replace or clean your brake pads and clean the rim with solvent (expect squeaky brakes for a while if you use solvent).
8. Don't cut off excess shift or brake cable after the attachment point.
The extra length (about 2 to 3 inches) is there so that when the cables stretch, you have something to hold onto to pull the cable tight. You will need to replace your cables the next time they need to be tightened if you cut off the excess.
9. Don't raise your stem or seat post beyond the max line.
Seat posts and handle bar stems should not be raised out of the frame beyond their maximum lines. This prevents component failure due to fatigue from over extension. If you are not sure if your bike has a handle bar stem or seatpost above the "MAX" line, check for a line on your handle bar stem or seatpost before you ride the next time.
10. Don't tighten things that should not be tightened.
Some of the most common things that are tightened that should not be tightened without some knowledge of the outcome are, derailleur adjustment screws, spokes, axle cones, and threadless stem caps. See future "Wrench Connections" for details about what to tighten and what not to tighten.
Questions or Comments Welcome