Letís assume youíve got a bike you love. Letís further assume that you carefully shopped for a bike saddle (seat), test rode a wide variety, and found the one thatís perfect for you. Somethingís still not right, however. Perhaps youíre slipping off the front or you have to keep pushing yourself back on the seat. Maybe your girl (or boy) parts hurt. Itís even possible youíre too close to your handle bars or your knees are bothering you. Simple adjustments to the position of that perfect saddle could help solve all of these problems.
Your average saddle has a set of rails under it which mount to the seat post. The seat post then fits into the seat tube and clamps into place. Adjustments can be made to how far into the seat tube the seat post goes (thus changing seat height), as well as to where on the seat post the rails are clamped. A combination of adjustments can drastically change how comfortable your ride is. One caveat: all of these suggestions presuppose that your bike is the right size for you to begin with. No amount of seat adjusting will compensate for a bike that is much too small or too big for you.
Letís start with seat height. For road biking, conventional wisdom says that when you pedal your knee should be almost straight at the bottom of the stroke to achieve maximum power from each stroke. I also find that this position is the most comfortable and least problematic for my knees. If youíre stretching to reach your pedal at the bottom of the stroke, your seat is too high and needs to be lowered a bit. This can be done by loosening the seat clamp and sliding the post further down into the tube. If, however, your knees are still quite bent at the bottom of the stroke, or if you feel like your knees are in your chest at the top of the stroke, your seat is too low. Loosen the clamp and raise your seat, but not above the marked maximum height line on the seat post. It just wouldnít do to have your seat come off while youíre riding.
Once you have your saddle at the right height, letís play with how the rails sit on the post. With the clamp that holds the saddle to the post loosened you should be able to slide the rails forward and back a couple of inches and rock the front of the seat up and down. Adjusting both can be very helpful.
The easiest is adjusting the seat angle by rocking the nose up or down. If your privates are being overly compressed when you ride, you may want to angle the seat nose down a bit. Not too far, however, or youíll feel like youíre sliding off the front of the seat and youíll have to keep pushing yourself back with your arms Ė very tiring. Try starting with your seat perfectly level and then adjust from there. This adjustment isnít difficult, so keep playing with it until youíve got it right.
How far back the seat rails are slid on the post affects how far back on your bike you sit, and even that couple of inches can make a big difference. If you feel like you have to reach for the handlebars (and the problem isnít that your bike is too big), try sliding the seat forward to see if that makes the reach more comfortable. If youíre too close to your handlebars, try sliding the seat back. This adjustment doesnít have to be all or nothing; an incremental change can be huge to your comfort.
Pedaling efficiency and knee comfort can also be affected by how far back the seat rails are slid on the post. For road biking, it is suggested that you want your forward knee to be bent at a right angle (90 degrees) when the pedals are held level (at the same height). This angle is easiest to determine if you have someone observe while you ride. If your knee is bent at an acute angle (your calf is closer to your thigh than 90 degrees), your seat may be a bit too far forward. If the angle is obtuse (more than 90 degrees) your seat may be too far back.
Unfortunately, there is no magic formula for how to position your saddle on your bike. Itís primarily a matter of comfort. Additionally, making one adjustment may affect others. Taking the time to get it right, however, is well worth the effort.