Broken New Ultimate Seatpost....

Discuss light weight issues concerning road bikes & parts.
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ElDuderino
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by ElDuderino

So all this talk about "true weight weenieism" and "practical weight weenieism" bring up this post...

I had my first collegiate race weekend of the year on saturday and sunday. I recently installed a new ultimate seatpost on the bike....great post. super easy to asjust. 93 grams...and best of all...it isn't carbon (won't slip, crimp, etc). It was solid in training the week prior to the race weekend. It was solid during the TT, and the TTT on saturday....then come Sunday, 50 meters from the line....the post sounded like it broke to a billion pieces. I sprint seated (like Zabel), and was in contention, until it broke. "true weight weenieism" lost out to practicality. Ah well. That's not what i'm starting a discussion about, however...

I was wondering if anyone knows where I can get a replacement bolt for this product? I should mention, that the seatpost itself did not break, one of the two Ti clamping bolts broke at the head. I weigh 164lbs, and am well inside the set weight limit of 190lbs. It's a great post, and I want to continue using it...maybe replacing the bolts with steel ones? If anyone has any info/insight, please let me know. I'll post photos of the broken bolt soon.

-Dude

that's me in green, white helmet...the photo highlights the predicament pretty well...you can see the slr floating around right behind...
Image
Last edited by ElDuderino on Fri Apr 29, 2005 4:52 pm, edited 2 times in total.

Mr_Potatohead
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Joined: Thu Jun 10, 2004 5:31 pm

by Mr_Potatohead

McMasterCarr will have all sorts of metric bolts in stainless maybe titanium too.


If it was a bolt breaking I'd suspect it was a fatigue failure possibly from not tightening it enough ironically. You can help get more tension in the bolt by using moly grease. That may be a problem if you have carbon rails on your saddle since you don't want to crush them.

A good titanium bolt will be just as good as a steel bolt, in some ways better because when the joint is loaded the fastener will take less of the load and the clamped surfaces will take more since titanium is about 50% as stiff as steel for a given cross sectional area.

Torque isn't a good indicator of bolt tension since friction effects produce huge variability in the bolt tension for a given amount of torque.

The best method is measuring bolt stretch.

The more you tighten a bolt the less probe to fatigue failure it will be, that is until you yield the bolt. So the trick is to bring the bolt up to about 80% of yield.

big fellow
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by big fellow

gee dude that's just plain bad luck mate

that's the last thing you'd expect after paying that much for one!

give some feedback if you do change bolts, may do the same as I wight more than you!

cheers

shinkansen
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Joined: Tue Jan 18, 2005 2:37 am
Location: Colorado, USA

by shinkansen

That's what I class as a TRUE WEIGHTWEENIE... Ditching your seat mid-sprint to save excess weight. Niiiiiiiice!

New Ultimate
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Joined: Tue Jun 22, 2004 11:51 pm

by New Ultimate

Hi Elduderino

We allways wants our products to finish first - and in one peace :-)
The torgue is not critical in this bolt (allthough Mr Potatohead has a point - 2,5 - 3nm should be use as torgue)
The bolt is one of the parts that is "overdesigned" - we have done testing for a long time with 4mm bolts on cyclecross bikes - without any problems...
For all the testing we have done - with 4 and 5mm bolts - we have never had a failure ! Same bolt we use for our longer 350mm version - wich has bin tested on MTB - never had a failure...
Only reason I can see to this failure is a "error" in the titanium material used for the bolt... wich is extremely rare - and impossible to detect...
But anyway - very sorry to hear this - we will of course send you a new bolt asap - send me PM

Best regards
Jesper
New Ultimate

newbieweenie
Posts: 358
Joined: Fri Jan 07, 2005 4:39 pm

by newbieweenie

Now thats what I call customer service. :) I see a new ultimate post in my future, simply because of that reply. How much do they run US $?

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BikeTech
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by BikeTech

Racing in Gainesville eh ElDuderino :)

What was your time for the ITT on Saturday?

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ElDuderino
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by ElDuderino

You a fellow collegiate weight-junkie racer? My ITT time was 26:50 . You do it as well?

an update on the New Ultimate post: I'm in contact with Jesper, and the customer service so far has been terrific. I will update with information as I receive it.

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OLver
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by OLver

big fellow wrote:that's the last thing you'd expect after paying that much for one!



... in my opinion, it's the first thing you expect from a 93g seatpost.

more expensive, lighter, weaker

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Samu Ilonen
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by Samu Ilonen

OLver wrote:more expensive, lighter, weaker


Not nessery on every time, every part. It needs just better design/testing/analyse and better/more expensive materials...I bet that my Stiletto fork is stronger than anything what exsample Kinesis has ever produced, least road forks...

2002SaecoReplica
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by 2002SaecoReplica

ElDuderino wrote:You a fellow collegiate weight-junkie racer? My ITT time was 26:50 . You do it as well?


Faster than me by a bit. Mine was 32.26 racing collegent C's. C's crit racing is scary, I'm thinkin B's might be a safe place next race weekend. Green and white, you're a Lee's Mcray boy then correct? I'm over on the University of Georgia team.
- Zipp rims will break if you look at them too hard
- R-Sys wheels will spontaneously explode
- The ZG crankset will never, ever exist
- Everyone needs Lightweights, even if they're fat and old
- Parts actually made of metal are SO 10 years ago

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ElDuderino
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by ElDuderino

... in my opinion, it's the first thing you expect from a 93g seatpost.


Cmon now....as if heavier seat posts have never broken...


and yeah, i'm a Lees-McRae student

marko
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by marko

Can you get it to work without the saddle or do the old school rules ban no saddle?

carlos
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Joined: Wed Feb 25, 2004 4:04 pm

by carlos

OLver wrote:
big fellow wrote:that's the last thing you'd expect after paying that much for one!



... in my opinion, it's the first thing you expect from a 93g seatpost.

more expensive, lighter, weaker


agree 100%

:exactly:
hey
ho
lets go!

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Pedä
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Location: Germany

by Pedä

could you post a picture of the broken bolt? :shock:
Pedä

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