Clydesdales/Athenas (200+ lb / 91+ kg) - Broke my seat post on Saturday...

... I was just about to crest the hill at my half way point of my 20 mi ride, sitting back on my saddle and powering up the last portion of the hill and all of a sudden my saddle rotated backward. I stood up on the pedals and looked back and saw my saddle hanging by the stem strap of my wedge pack. The post broke just below the saddle bracket insert and it left a 4 ish inch spike with sharp edges protruding in place of my saddle! Luckily I didn't drop onto the post or I could have been in some serious trouble.

I walked my ride to the top of the hill and went to pull my cellphone out of my jersey pocket and it wasn't there!!! I always take my phone on rides. Anyway, I was able to use a fellow cyclists phone and the wife and kids came to my rescue. When I got home I found my phone inside the plastic baggie (I put my phone in a snack baggie to keep it sweat free while riding) inside the drawer where I keep the baggie! :eek:

Before calling my wife, I removed the broken stem and inserted the remaining inches of stem attached to my saddle into the seat tube and tried to ride it... way to short - felt like I was riding one of my kids bikes!!! That afternoon I went to LBS and bought a new seat post and all is well in my cycling world. :)

The seat post was the stock Bontrager that came with my Trek 5200 and it had a little over 8k miles on it. I repalced it with an aluminum Easton post.

I had one fail a couple of years ago. Quite a scary feeling. I replaced mine with a Thomson Elite. So far, so good.

Yep my stock Bonty CF post failed on my 06 pilot too.

Back in my MTB days when I'd do big drops and ride down long staircases on campus, I bent a seatpost; but I never snapped one clean in half. Just lucky, I suppose. I have the stock post on my Cross Check, with about 5" sticking out from the seat tube. So far (2560 miles) it seems to be in good shape. *knock on wood*

Don't feel bad. Jens Voigt did the same thing during Stage 21.

Oh great, this is what I have to look forward to.

We're talking about breaking carbon fiber posts here. I doubt anyone is going to snap a alum. one. Maybe bend it but not snap it.

Yeah I have a bonty CF seat post on my Trek. So...some day.

CF seat posts are not good for people on this forum. Thomson are great, or if that is too pricey, some other alum post.

I am talking about an aluminum seat post.... not a CF. My frame is CF but not the seat post.

I am talking about an aluminum seat post.... not a CF. My frame is CF but not the seat post.


Wow, aluminum? How much do you weigh? I have a Bonti CF on my Lemond, no problems after 15,000 miles (220-245 lbs). But all road riding, no hopping curb stuff!:D

Swapped out my CF for a Thomson as well.

Oh the carnage!:eek:

It's a bit scary hearing an aluminum post failed. Kind of makes ya shudder just a bit.

Wow, post some pictures of that. I've never seen an aluminum post snap off!

Whoa...agreed. You must have hit the fatigue limit on that sucker.

I weigh ~250. No curb hopping or anything like that and when I do go over RR tracks or potholes I am out of the saddle. I will take a pic and attempt to post it from work tomorrow. Anyway, it is a 27.2 dia Bontrager Race black anadized aluminum seat post.

I'm thinking there was some sort of internal flaw and I hit the fatigue limit. When looking at the break, it looks to me like about a quarter of the circumfrance material is chalky looking and the remaining 3/4 looks like shiny metal... possibly it was just a poor casting.

I'd e-mail trek and let them know about it. They'll probably want to see the post and will likely offer you a replacement (and who knows, maybe some other swag as well).

Even if they tell you to go pound sand, you're just out the cost of an e-mail.

Here are some pix of the seat post (hopefully)

Here are some pix of the seat post (hopefully)

Now I'll have nightmares after looking at these pictures.
Pretty scary to see, OUCH!!!

It happens. I had an aluminum American Classic seatpost fail. At the time, I weighed 215. In my case, however, the shaft didn't break, the setback at the top of the seatpost failed catastrophically.

The failure caused me to fly right off the back of the bike at around 25mph. The crash resulted in a broken left wrist and an absolutely obliterated right thumb. After four months, a couple of surgeries, and some painful rehab, my hands are now working again. Thanks American Classic!

I'm sorry. I don't mean to worry anyone unnecessarily; I'm sure your aluminum seatpost will be just fine--especially is you're using a Thomson seatpost; they're really are super nice.

Kid-Cycle, I'm glad to know that you're okay. I suspect your Bontrager failure was an anomaly. But I would definitely e-mail those photos to Trek. They need to be aware of this.

I'll send the photos to Trek just to inform them of what happened. Since I've already replaced the post I'm not looking for anything. The response on this subject suprised me... I didn't really think much about the rarity for a seat post fail... I was just thinking about the possible injuries such as gazza had.

Wish I would have heard all the good viewpoints on Thomson seat post before buying an Easton... My Easton seems pretty beefing so I'm good.

Hard to tell from the blur, but that looks a lot like a fatigue failure. The metal has that dull gray crystallized look.

Hi,
I have a cross check also and about 3 weeks ago the bolt holding the seat clamp broke in half as I was getting some speed up. I don't know how I was quick enough to stand up. Anyway I had my saddle as far back as it would go, a bit past the nmbers on the rails. I am assuming that helped or lead to the break. I replaced it with a mountain bike seat post thinking it would be stronger - it has a two screw clamp.