Broken New Ultimate Seatpost....
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- ElDuderino
- Posts: 762
- Joined: Thu Apr 08, 2004 3:31 pm
- Location: Hollywood
- Contact:
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...
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...
Last edited by ElDuderino on Fri Apr 29, 2005 4:52 pm, edited 2 times in total.
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- Posts: 125
- Joined: Thu Jun 10, 2004 5:31 pm
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.
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.
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- Posts: 1288
- Joined: Thu Nov 04, 2004 4:05 pm
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
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
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- Posts: 200
- Joined: Tue Jan 18, 2005 2:37 am
- Location: Colorado, USA
That's what I class as a TRUE WEIGHTWEENIE... Ditching your seat mid-sprint to save excess weight. Niiiiiiiice!
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- Posts: 28
- Joined: Tue Jun 22, 2004 11:51 pm
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
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
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- Posts: 357
- Joined: Fri Jan 07, 2005 4:39 pm
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 $?
- ElDuderino
- Posts: 762
- Joined: Thu Apr 08, 2004 3:31 pm
- Location: Hollywood
- Contact:
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.
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.
- Samu Ilonen
- Posts: 2155
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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...
Samu @ www.signature.fi
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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
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- 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
- ElDuderino
- Posts: 762
- Joined: Thu Apr 08, 2004 3:31 pm
- Location: Hollywood
- Contact:
... 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
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