Thursday, September 4, 2014

Circling the Toilet: I am Out of Shit to Say

I would like to circle back to seats, seat posts, and how to use them. It is important to have a well maintained seat post for several reasons. Beyond needing to be the correct diameter, there are a few other rules to live by when it comes to seat posts;
  • They must be installed with grease or assembly compound (carbon paste)
  • Just like a quill stem, a seat post must also be installed to AT LEAST max height (or minimum insertion)
  • They MUST be regularly maintained (two or three times a year) like any other part on your bike.
Let's start with carbon seat posts. Carbon in itself is light, and dampens vibration. That makes for a good seat post... for the most part. Carbon posts can get stuck inside steel and carbon frames very quickly if not maintained. If your post gets stuck, you may have to resort to desperate means to remove it from your frame. This includes, yet is not limited to, having to cut out the post. In some cases, this is dangerous for your frame and in all cases, sucks for your expensive seat post.
So, how do we avoid this? It is easy!  If you have a non-carbon frame or post, You simply apply grease liberally to the seat tube of the frame as well as a film of grease on the post, insert and clamp down. 


In the case of carbon posts, one must use a carbon assembly compound (often called carbon paste).
Similar to grease, it acts as a moisture barrier to keep the post working smoothly. Beyond that, it's primary function is to allow for max grip at minimal torque. That is to say, keeps your post tight, without clamping it to the point of "biting" your post.

 (although more common in steel and aluminum frame applications, this is what happens when you over tighten your seat post binder on your carbon seat post)

The paste is able to provide this force by using tiny bits of carbon which coat the surface, making it feel like sandpaper.

(Carbon paste)

Where people often get in to trouble is that a seat post is one of a few things that once we install on a bike, we rarely move. The problem with that is grease and paste are only so water proof, meaning, given time and exposure to the elements, eventually the compounds will break down and wash away. This leads to corrosion in steel and aluminum frames and leads to carbon-on-carbon friction in carbon frames. Imagine rubbing together two pieces of construction paper, only instead of the paper being thin and flexible, imagine it as thick and unforgiving. It is that amount of friction that can make it damn near impossible to move the post enough to break that friction barrier. 

So, you got your post stuck anyway, eh? Well it's a good thing for you that I am experienced in fixing your misgivings. Thanks to my lovely assistant Greg, I present you with the only solution he has found to the worst seat post we have encountered...   

The entire industry should thank him.

Thanks Greg!

That's right, after using the seat itself as a lever, after clamping the shit out of the post in the repair stand and trying to rotate the frame, after trying to drip lubricants into the frame and post interface, it was the humble screw driver that was the answer. Clamp two of them where the saddle rails go, and apply torque by trying to rotate the post back and forth. It will sound like you broke it, but it will get results. If not, start cutting ;)

Nextly, one must observe minimum insertion. This is not an arbitrary number, rather a number that assures you your post is far enough inside your bike to avoid this:


Most manufactrers advise a minimum depth of 100mm (ten centimeters). Really, this number is designed to be sure your post goes beyond your seat stays. 
After checking this (to get a warranty replacement for this guy) it was in fact, beyond the stays (about here) 

However, minimum insertion has it's limitations (pun intended). This is a 62cm frame (that's really fucking big). As such, at a depth of 100mm, it may not be enough. Here you have a tall dude and a seat post that is barely inserted enough to meet the recommendations. After a few years and approx. 15,000 miles, this frame was destined for failure. Not like this one:

(Same exact frame. Failed due to negligence)  

But fucked nonetheless. 

I will be sure to recommend he use a longer post, as the manufacturer is indeed replacing this frame because they are pretty fricken awesome.

Moving on... what you sit on is about as important as what it rests upon, so your choice of seat (or "saddle" as I have been to lazy to type all this time) is just as important. While it may take you forever to find a "saddle" that works for you, let me say this: you can go to your LBS and ask them what might be right for you, but in the end, you will do what you want. That may lead to you finding exactly what it is that works for you, with the assurance that if you don't like it, you can return it, or you can get one from China on eBay and end up with this:
 If your saddle looks like this, you are a weight-weenie AND a cheapskate.

I would be lying if I said I have not seen this happen at least three times. 

Sure it is a light saddle and did not cost as much as its carbon counter part, but to that I say, Your carbon counterpart is bull shit as well if it looks like this after one ride:

Born as a cheap, light weight alternative to spending your money on a quality saddle, it is now spending its life as a trophy...

(The Northern Indiana Mountain Bike Association's "Traveling Hard Ass Trophy.") 

Initially awarded to its original owner, for finishing a 12 mile race with NO saddle. Passed on to a man who rode across Indiana one day, and finished in first place in his race the next day. Two weeks later passed to a man who finished his race with NO FUCKING FRONT TIRE, now residing in the hands of a man who finished with NO CHAIN (literally balanced-biked to the finish)

As cool as it sounds, it still stands as a result of "getting what you paid for it."

I don't know about you, 
but I wouldn't mind having a secure place to rest my ass. 

Seats, and seat posts... two things that often get neglected, but need to be maintained properly in order to keep your ass in one piece.

Now you know.

...and your ass will thank you for it.