Inspecting your frame

Even though the frame may appear to be one solid, immovable object, it’s not unheard of for them to go out of alignment occasionally. Any kind of impact — whether it’s an accident, your bike falling over, or jumping your bike over a curb — could impact the alignment.

To inspect your frame for issues, follow these steps:

1. Stand in front of your bike and peer down the center of the frame (as shown in Figure 12-3).

You should see the head tube line up with the seat tube.

2. Facing forward, straddle your bike with both legs and look down at the frame (as shown in Figure 12-4).

You should see the top tube line up with the down tube. The front forks should also be equidistant apart from each side of the wheel.

3. Stand behind the bike and check that the seat tube lines up with the head tube (see Figure 12-5). Look down at the seat stays and make sure they are parallel.

Inspecting your frame

Figure 12-3:

Checking the frame from the front.

Inspecting your frame

Figure 12-4:

Checking the frame from the top.

Inspecting your frame

Figure 12-5:

Checking the frame from the back.

4. Visually inspect the frame for defects (as shown in Figure 12-6).

Pay particular attention to where the frame is welded together. For hard — to-see places, close your eyes and run your fingers along the side of the tube. (Closing your eyes allows you to actually feel and not have your eyes trick your brain.) If you see or feel bubbles, ripples, or cracks in the paint, it could be a sign that your frame has issues. Take it to your local bike shop for further inspection.

5. Tie a string to the rear dropout on one side, and run it toward the front of the bicycle head tube and then back to the dropout on the other side and tie it.

Inspecting your frame

Measure the distance from the string to the seat tube on each side. If the measurement’s are not exactly the same, your frame is bent and out of alignment.

If you think your bike is out of alignment, take it to your local bike shop. Many shops have tools that can check the alignment and straighten the frame as needed. If your frame is made of steel, repairing it is usually much easier than if you have an aluminum, carbon, or titanium frame. If your frame is not made of steel, your best bet might be to turn to your bike’s warranty.

Inspecting your frame

Figure 12-6:

Checking the frame for defects.