lungimsam

Please check your Giant stock composite seatposts on your bike for cracks.

My second stock composite Giant seatpost has now cracked. That makes two cracked on this model in 3 years. You can even see it cracked all the way thru on the inside of the post.

About 1.5 years ago, my stock compsite seatpost cracked. It was replaced under warranty with the same model seatpost.
Today, I was raising this warranty replacement seatpost a little and decided to inspect it just to be safe since the first one had cracked. This one was already cracked worse than the first one. The LBS told me not to ride on it anymore, and they are getting me an aluminum seatpost from Giant to replace it. I am done with the composite/carbon seatpost for this model at this point.

I followed the recommended torque specs and have kept the seatpost clamp oriented how I got it from the factory, and the post still cracked. So, I don't know if this is a recall issue or not. But thought I'd let you know so you don't get any surprises while riding.

Don't get me wrong, I love Giant bikes and my Defy 3. Just this moel seatpost is not working out for me.

GiantDefyGuy

I have one, and it's not cracked. I'd think that there would've been more cases of this happening in the last 4 years if it was really an issue.

I also think that, since you have cracked 2 of them, that it's either something you're doing or something else is wrong with your seatpost collar or your torque wrench. Maybe there's a tiny rock embedded in the slit in the seat tube or something like that.

I hope the alu one works out for you. That sucks that you are having this problem.

lungimsam

Thanks for the suggestions. I will inspect/clean the seat tube and collar to be sure it is clear of foreign matter.
I have used my Ritchey 5nM torkque key, and not even got it to the point of 5nM, so I think I am alright there, not passing the Giant 5nM spec. Unless the torque key is defective, but I have no idea how to check that. Maybe just chuck it and use something else.

lungimsam

double post. sorry

Mobile 155

How did you get a composit seat post on the Defy 3? I thought it was Aluminum so did you get a CF upgraded Seat post?

lungimsam

The original seatpost was composite. I bought the bike on April 13, 2009.
If I remember right, the pic on their site at the time showed the composite post. I remember you could see the weave.

But as of April 19, 2009, the spec on their site was written as "Giant Alloy, 30.9". I printed the spec sheet for my records at that time. Maybe the spec suddenly changed?

lungimsam

PS- sorry, everyone, about the "BEWARE" in the title. Just wanted to grab owners' attention so they could read about the seatpost issue in case they have one.

Mobile 155

Ok but is your Defy Aluminum? Is it an Aluminum frame that is. The Giant CF seat post isn't much lighter than a stock Aluminum seat post and if you have been having a problem you can either try a different CF seat post or switch to a light weight aluminum one. I had a Giant CF seat post that lasted me 2 years with no problems on my Lapierre. How much set back are you using? is the saddle all the way forward or all the way back?

lungimsam

It is an aluminum frame with a composite fork and seatpost. I think the seat is centered pretty well on the post. So I don't think it is set back too far. I keep it 45.5 cm from nose of saddle to middle of bar tops. 71cm from center of crank to top of saddle, measured up along the seat tube. I am short with short reach.

Only mods have been the brake pads, FSA Compact Omega handlebar, 39t middle ring, shorter stem, Speedplay Frog pedals, Zefal locking QR skewers, and Specialized Avatar Saddle. Here she is with a rack:

I'm definitely putting an aluminum seatpost on it now. LBS is going to get a Giant aluminum seatpost for it.
I'm glad I got it in 2009, as I don't like how the Giant bikes are looking after 2010. I love it. Rides and looks great. Only complaint is I would like to be able to get the bars higher.

lungimsam

I cleaned and checked out the seat tube and the clamp. No foreign matter I could see. But I will say that the edges of the seat tube notch on the inside of the frame are a little on the sharp side and it looks like they get compressed right against where it cracked when the clamp is tightened.

lungimsam

lungimsam

Today the LBS said another guy came in with the same thing, same model, but it looked like he has been tightening it too much.
Giant will not cover it under the waranty this time. I can understand that.

Nightshade

Since a seat post is critical to your ability to control your bike I'd stop playing footsie with the damn thing and replace it with a solid aluminum ,or steel, bar to be done with it!!

Sometimes being a weight weenie will bite you in the ass. This is one of those times.

GiantDefyGuy

Weight weenie? Lol. You know we're talking about the stock seatpost on a $700 bike, right?

chasm54

I hear what you say about the torque wrench, but that seat post looks as if it has been over tightened to me...

lungimsam

Can't wait for the aluminum seatpost to come in this week.
Is there a torque limit on an aluminum seatpost, or just snug it up until it doesn't move anymore when you twist it to test it for movement?
Carbon makes me nervous, what with all the controversy. I am glad to have aluminum replacing it. One less thing to worry about failing on the bike.

Nightshade

Price don't mean a thing really. It's all what the market will bear.

Be that as it may.....If a component isn't doing it's job find one that will..price be damned.

Nightshade

Replace the tightening bolt also since was intended for use with the carbon post and may not be strong enough to really wrench on.