Litespeed Sewanee Rubbish

[Capricorn]

i'm not convinced this is impact damage. the photo appears to be somewhat ambiguous. I do agree on teh need for more photos from different angles. Off the bat, i dont see real impact damage. if u hit something hard enough to dent a fram, it leaves scratches and the other abrasion damage. But again, without proper evidence, and our instance of the armchair CSI (crash spot investigators), better images from various angles are required. Also, could u hold a ruler in each photograph to as to help gauge defect size etc

[Minion]

From the diagonal crease in the first photo, it appears that the tube has buckled. The cracks are then as a result of the buckling.

This buckling could be caused by an impact to the front wheel/shock or to the head tube. It doesn't look like a direct impact to the down tube, hence no scratches.

[Mecnic]

From the diagonal crease in the first photo, it appears that the tube has buckled. The cracks are then as a result of the buckling.This buckling could be caused by an impact to the front wheel/shock or to the head tube. It doesn't look like a direct impact to the down tube, hence no scratches.

 

I am inclined to agree with Edam but as stated more pictures better angles and a ruler as Capricorn pointed out

[Capricorn]

Edam: ever see a down tube buckle like that? neee, not without direct impact, or an existing flaw revealed by the fact the bike is ridden. I'm with MHattingh on the need for context as well: was the bike being used as dictated by it's stated limits (intended use, maximum rider weight restrictions..etc etc).

[Johan Bornman]

Photos not clear. However, I think your'e trying to BS yourself and looking for moral support to make you feel better about your loss.

 

From where I sit it looks like a buckle due to head-on impact. A too-big drop-off or riding into a tree.

 

Come clean. This didn't happen from riding your bike to church.

[Minion]

Edam: ever see a down tube buckle like that? neee, not without direct impact, or an existing flaw revealed by the fact the bike is ridden.

I've never seen any tube buckled on a bike, but the damage looks a lot like buckled tubes I've seen in other places.

 

Some form of compression would be needed to cause the buckling and the lack of other damage in the area would seem to indicate that this compression was not from a direct impact to that area. This would leave the likely possibility that the compression load occured elsewhere, either at the BB end (unlikely, I think) or at the headtube end (which could be the result of some impact to the front wheel).

It is not unexpected that a compression load would cause the tube to fail at that point, but presumably the designers knew this and designed the tube (with depression) to handle all expected loads from normal use.

 

The fact that the tube failed in that particular place is an artefact of that specific design, but does not necessarily mean the design is flawed. For all we know, the same load could have caused a normal tube to fail somewhere else.

[Capricorn]

I'll be honest,i think that fold in the down tube is a flaw that increases the risk of buckling if the load to that area is just right. I guess the engineers would try to cover that by stating the limits of performance, aka, light XC, no jumps no drops, rider weight restrictions etc.

 

I know large span panels have crease lines to increase the stiffness,but it's not increased by orders of magnitude. On a downtube, with forces exerted by teh fork on to it (front impacts to the wheel), the force translation down the tube is interrupted by the creases. The top of the downtube goes into tension and the bottom under compression. with those creases punched in toward the center of the downtube, those compression forces are having an easier time of causing buckling. At least according to my simple mind that is..

 

No else does this, and this company has stopped doing it. It's poor design IMHO. But we need more info, starting with how the rider rides and what he was doing on the day...and no sugarcoating pls

[MintSauce]

ever see a down tube buckle like that? neee, not without direct impact

 

I have seen it happen....when a friend fell off his bike and in losing balance went offline and stuck the front wheel directly into a tree. The fork is, obviously, designed to take huge strains so in such an instance transfers the impact to the frame

 

 

 

Photos not clear. However, I think your'e trying to BS yourself and looking for moral support to make you feel better about your loss.

 

From where I sit it looks like a buckle due to head-on impact. A too-big drop-off or riding into a tree.

 

Come clean. This didn't happen from riding your bike to church.

 

Saying what I was thinking when I first saw this.

Edited February 21, 2011 by MintSauce

[Wyatt Earp]

Photos not clear. However, I think your'e trying to BS yourself and looking for moral support to make you feel better about your loss.

 

From where I sit it looks like a buckle due to head-on impact. A too-big drop-off or riding into a tree.

 

Come clean. This didn't happen from riding your bike to church.

:clap:

[Minion]

The top of the downtube goes into tension and the bottom under compression. with those creases punched in toward the center of the downtube, those compression forces are having an easier time of causing buckling. At least according to my simple mind that is..

I agree, the crease does increase the chances of buckling. I'm just noting that you can either offset this by reducing the applied loads (setting weight/usage limits etc.) or by strengthening the tube in that area (e.g. increasing the wall thickness). I could design a normal tube and a creased tube with the same buckling characteristics and strength; although it is likely that the creased tube will be heavier.

It may not be an optimal design, but I don't necessarily agree with the OP that it's a flawed design.

Edited February 21, 2011 by Edman

[Zeps]

:clap:

 

Boris are you implying this cannot happen when JRA is taking place

[LazyTrailRider]

JRA!

 

That's the word I was looking for.

 

I was Just Riding Along when my frame collapsed underneath me and sent me sprawling teeth-first into the car which was Just Driving Along next to me. As a manufacturer, you now owe me R1bazillion in compensation.

Edited February 21, 2011 by Martin Hattingh

[Zeps]

JRA!

 

That's the word I was looking for.

 

I was Just Riding Along when my frame collapsed underneath me and sent me sprawling teeth-first into the car which was Just Driving Along next to me. As a manufacturer, you now owe me R1bazillion in compensation.

 

Spot on dude

[Guest Big H]

Anybody else has a pic of what a new Litespeed frame would look like for comparison. That would prove the existence of the "dent"

[DJR]

The full term is J.R.A.M.M.O.B. (Just Riding Along Minding My Own Business)

[Sewanee]

I have had three sewanee's over the years. I have never experienced the problem mentioned. I cannot say that I had a crease in any of the frames as mentioned. It would have been visible as it would have stood out like a sore thumb. They are great frames made by a great company. One of the best racing frames out there.