Bike Seat Posts
As the primary support of your body weight, seatposts are a critical component for maintaining a comfortable and efficient bike. For the most part, seatposts are utilitarian in nature. For recreational riders, the seatpost that comes with your bike will probably last the duration of the bike's life. As long as it allows adequate saddle adjustment, and holds when tight, your post is doing just fine.
Fast recreational riders and racers realize seatposts can be relatively heavy. A new seatpost can easily save 100 grams or more, which makes them a popular weight saving upgrade.
As with all components these days, seatposts are made of carbon or aluminum. Carbon posts provide more dampening of road vibration, while aluminum saddles deliver stiffness and generally cost less. Steel seatposts are fairly common on older bikes, but few after market steel seatposts are available. Campagnolo, Easton, FSA, and Thomson are just some of the seatpost manufacturers we carry at BikeTiresDirect.com.
The flashiest seatposts available are made of carbon fiber. Easton 2012 EC90 Zero Carbon Seatpost 31.6 and FSA K-Force Lite Carbon Seatpost are high-end carbon posts with lightweight aluminum seat clamps. A carbon seatpost will smooth out the ride of an overly stiff frame and probably save a fair amount of weight over most stock seatposts.
Carbon seatposts might not be for everyone. Compact frames, such as a Giant TCR, often require a large amount of exposed seatpost and have rather sharp seatpost angles. If your frame leaves over eight inches of seatpost exposed, we advise sticking with an aluminum post.
Aluminum seatposts deliver many of the qualities of carbon, light and stiff, at a lower price. The Thomson Masterpiece Seatpost is a great lightweight seatpost with excellent reliability, at 158g (for the 27.2 seatpost) it is also the LIGHTEST post we carry. Thomson makes some of the most reliable stems and seatposts on the market.
Profile Design Fast Forward Carbon Seatpost is designed for time-trial and triathlon riders who prefer to be positioned over or in front of their pedals. This allows them to maintain aerodynamic positions and emphasize the muscles most effective when traveling over flatter courses.
The corroded/seized/stuck Seatpost
For some chemical reason, carbon fiber likes aluminum. Aluminum seatposts can run the risk of seizing to a carbon frame, and vice versa. When left in contact for a long period of time, carbon and aluminum will bond together making seatpost adjustment difficult if not impossible. Seized seatposts are a result of improper installation. Seatposts seize when they have not been adequately greased before installation. A good smear of Finish Line Synthetic Grease Tube 3.5 oz. prior to installation will prevent seizing.
A seized seatpost isn't common, but it happens. If your bike has been sitting for a couple of years and you can't adjust your seatpost, hope is not lost. You're probably going to have to pull that bottom bracket out and see if you have a hollow seat-tube (Bianchi is a popular brand which often doesn't). If so, make sure the top end of you seatpost is fully sealed (if not, plug up the hole), get a can of Coke and pour it down the seat-tube and let it sit overnight. Seriously. I don't know much about chemistry, but there is something in carbonated sodas that loosens up seized parts. Just be careful once you get the seatpost to budge that you don't get coke all over the place, and flush it out thoroughly with some sudsy water so you aren't wondering where all those ants are coming from next summer.
Steel seatposts and frames, often found in older bikes and high-end custom bikes, run the risk of corrosion. Corroded steel parts are even more of a problem than a seized aluminum part. If you're experiencing corrosion in a steel frame, take it to a mechanic. Always install steel posts with a touch of grease.
If your post is stuck, but you don't think it's thoroughly seized, flushing it out thoroughly with WD-40 or Tri-Flow and letting it soak in overnight will probably get it to budge.
As with any bike maintenance technique, be very careful. You don't want to crack a frame, or get a piece of cracked seatpost lodged in your frame. Seized parts are best loosened with patience, technique, and Coca-Cola rather than brute force. When assembling a bike, don't forget Park Tool ASC-1 Anti-Seize Compound, a specially formulated grease for seize prone parts. Contact us a firstname.lastname@example.org or 1-800-682-0570 for any questions regarding seatpost selection or maintenance.