Bicycle Fitting Instructions

By Author: Jamie Hanson
Total Articles: 3534
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Riding a bike is a great way to get in shape, save money, and keep the planet green. However due to comfort issues, people do not ride their bikes as often as they would like. We describe how to properly fit a bicycle to anyone. Following the easy to understand pictorial instructions will also make the bicycle at least 10% faster.

Part I Stem Adjustment
Set the stem angle to make sure you are sitting on your sit bones. Riders that overextend to reach the handlebars will lift their sit bones off the saddle. Many of these riders will misdiagnose fitting discomfort with a saddle problem. Bringing the stem closer to the shoulders will allow the rider to sit back on their sit bones and will solve most comfort issues. Follow the remaining steps to optimize comfort.

Step #1 Look at the stem and decide on the changes you want to make.
Step #2 Loosen the 5mm allen bolt on the stem to change the angle from 0 to 60 degrees.
Step #3 Change the stem angle as desired. Lift the angle higer, closer to 60 degrees,if you want to sit upright. Make the angle closer to 0 degrees if you want to ride in a tuck position. ...
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Step #4 Tighten the allen bolt.
Step #4 ( Optional ) Riders that want to sit completely upright, emulating a cruiser bike can do so on a folding Downtube. First remove the handlebar from the stem by removing the four 4mm allen bolts. Then loosen the two 5mm allen bolts that hold the stem to the steerer tube. Rotate the stem so it points toward the rider. Then tighten the two 5mm allen bolts attaching the stem to the steerer.
Step #5 Compress the right hand grip by pushing the shifter into it. This will give the right side cables more room to bend naturally.
Step #6 Move the brake lever towards the shifter to give the cables a more natural bend.
Step #7 Replace the handlebar with four 4mm allen bolts. Once finished the stem of the bike should look like the picture below. Becareful not to kink the cables when doing this operation. When completed, you will have a comfort bike feel on a suspended folding bike.
Part II Saddle Angle Adjustment

Set the saddle angle so that it will be level under compression of the riders weight. If it is not very comfortable you should set downward angle on the saddle not more than 5 degrees. Saddles that have an upward angle will almost always feel uncomfortable. Additionally, with a large downward angle ( greater than 10 degrees ) the rider will slide down the saddle while pedaling causing discomfort.

Step #1 Look at the saddle and decide on the changes you want to make. All adjustments should be made while seatpost is on the bike. Do not remove the seatpost to adjust....it will most likely end up uncomfortable.
Step #2 View the 6mm bolt on the seatpost from the below the saddle
Step #3 Loosen the 6mm bolt with an allen wrench. Turn it counterclockwise to loosen.
Step #4 Once the allen bolt is loosened the saddle can slide forward and back. If you have short arms pushing it forward will be more comfortable. If you are tall with long arms you will need to slide it all the way back.
Step #5 Adjust the saddle angle by tilting the saddle up or down. Ideally the saddle should be level while riding. Keep in mind the riders weight compresses the back of the saddle, hence the front should be tilted down at an angle of 5 degrees ( while not supporting a rider ).
Step #6 Tighten the 6mm allen bolt by turning clockwise.

Stage III Seatpost Height

Setting the proper seatpost height will allow the rider to ride faster with less pedaling force. The riders leg can never be completely straight while pedaling, this may cause cartilage damage if ones leg gets locked in the straight position. Additionally ones leg should not have too much of a bend while riding. A large bend at the knee will make pedaling hard, and will not be good for ones joints ( it is highly likely to cause knee pain ). At top dead center, the furthest pedal position from ones hip, the rider should have a 30 degree knee bend at the bone ( not at the surface of the skin ). Without a measuring device the knee should have a slight bend at the furthest point The ride will be amazingly comfortable once the seatpost height is properly set.

The proper knee bend ( which equates to saddle height ) is measured with the pedal at top dead center. The below picture has the pedal at top dead center, the furthest position from ones hip.
The riders leg can never be completely straight while pedaling, this may cause cartlidge damage if ones leg gets locked in the straight position. The below photo has the riders leg in a dangerous straight position with the pedal at top dead center. This rider should lower his saddle slightly.
Ones leg should not have too much of a bend while riding. A large bend at the knee will make riding hard, and will not be good for ones joints ( it is highly probable to cause knee pain ). The below photo shows a rider with too much bend in the knee with the pedal at top dead center. This rider should set his saddle higher.
The rider should have a 30 degree knee bend at the bone ( not at the surface of the skin ). The ride will be amazingly comfortable once the seatpost height is properly set. The below photo has a perfect knee bend with pedal at top dead center, hence a perfect saddle height.

Stage IV Saddle For-Aft Adjustment

The final stage will put your body in optimal position for power transfer to the pedals. When the pedal is in the 3 o'clock position the rider should have the bottom of his/her patella tendon directly above the ball of their foot. If it is not properly aligned push the saddle forward or back until it is properly aligned. This will set your power stoke, so you will ride with as much power as possible with minimal effort.
This is part of an advanced setup. It is not required for most riders.
One will need a couple feet of fishing line and a fishing weight as pictured below.
While the pedal is in the 3 o'clock position the rider should have the fishing line hang from the bottom of his/her patella tendon ( as pictured below ).
The weight should contact the rider on the top of the foot, directly above the ball of their foot as pictured.
Slide the saddle back, if the weight is in front of the ball of the riders foot, or slide it back if the weight is behind the ball of the riders foot.

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