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Posted (edited)

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

 

 

You can see under the "D" there is a dent.

http://www.nationalcycles.co.uk/evans/litespeed-sewanee-2010-mountain-bike-frame.jpg

 

http://www.litespeed.com/images/2011/Sewanee-Ti(1).jpg

 

But on this pic it does not have it.

http://www.jensonusa.com/product/FR/FR305H04.jpg

Edited by Mampara
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Posted

Wow - a lot of posts - i'll try to answer: I am 54 years old and i weigh 61kg. My front suspension is a Manitou Skareb with 80mm travel. It is not possible for the suspension to strike the frame The frame is a 2009 model and was bought brand new through Cecil Baker (the all Africa agent) in May of 2009. The reason i have done so little riding/racing on the bike is because i was out of the country until Feb 2010 and i have another old Trek which i use for messing around. The dent was put there by the factory and i have an email from them to prove it. They say 'for fork clearance and added front end stiffness'. There are absolutely no marks on the frame in the region of the damage. i will take more pics as suggested. it's difficult to see what's going on in the photographs because of the reflections off the tube (and i'm no great photographer either). A mate of mine bought a Merlin with a similar dent - it cracked too with no crinkles - Litespeed maintained that the frame had received a heavy impact and would not repair under warranty. I don't believe for an instant that there was any impact to the frame. I wash it after each ride and it was fine before the 2 x 15km Grabouw ride. I'm more likely to believe that the frame is just not suited to anything more than riding on dirt roads - even at R23k

Posted

Hmmm - and so the plot thickens.

 

Based on where you purchased it - and judging my Mampara's pics - I think it's safe to assume(?) that your particular model came out like that - so let's put that one to bed.

 

Pop up some more pics - not just close-ups of the damage, but side angles of the bottom tube area - including the headset and toptube join, prefereably with some reference items (either a ruler or a matchbox!) for scale purposes...

 

I'm pretty sure that it will spark some interesting contributions from the resident Hub engineers etc. etc.

 

:thumbup:

Posted

I can't make out a lot from the OP's pics - it looks like a symmerticaly buckled coke can to me.

 

Re. the design in general - I think putting a "dent" like that in the down tube is asking for trouble. This effectively pre-buckles the frame. What I mean by that is when a normal frame gets a hit on the front wheel that would buckle it, this is the area where it would buckle (other area is on the top tube) ffrom a front wheel hit. By putting the dent there, the force required to buckle it would be lower. The path of a buckling event depends on a trigger, and it looks like this dent provides one.

Posted

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.

 

 

A buddy of mine, after MUCH egging along, look a drop-off with his steel frame HT (Cove perhaps...?) in Eden on the DH course. He came pipe and his frame ended up looking EXACTLY as the OP pic: i.e. nice compression buckle in the dead same spot on the down tube where the disputed manufactured dent is. So ja, I'd say to put any from of stress riser in there is a massive oversight from Lightspeed and will lead to problems down the line, as reported by the OP with Marlin etc.

 

So if Lightspeed throws out the impact card, do they talk about direct impact as in hitting a rock against the frame (which will be nigh impossible it that location on the frame, since for the life of me I cannot see a rock/tree getting in there past the fork and wheel and going that damage without leaving any evidence) or are they saying you handled it too rough and threw too much abuse at it, which you must have noticed?

 

@Edman: Would like to hear how you would manufacture said tube from titanium? Serious question, no sarcasm.

Posted

Just had a look at my 2010 Merlin Ti frame - Also made by ABG. It has an identical flat spot just behind the steerer tube.

 

And it has to be said that they were a little bit sticky when it came to sorting you out when it broke(in a completely different location), right?

Posted

A couple of days after I'd started this thread, someone offered a Litespeed Sewanee frame (large) for sale on the Hub - there was no dent in the frame. I sent the pic to the Warranty Department and they came back asking about the dent in my frame and if i had proof that it had been put in by the factory. I have that proof - but the interesting thing was that they didn't seem to be aware of this 'feature'. It seems almost as though some frames have it, some don't. I submitted more photographs and explained exactly that i thought the tube had collapsed a la Coke can. This was their response:

 

During our warranty meeting today when we reviewed the claim on your frame, our decision still stands that the frame has received an impact at some point. We would like to work with you on this and offer you a frame at a reduced cost. I would like to offer you a Sewanee frame for $2,150 USD plus shipping. These frames are in stock now in Tennessee, so if you want the new frame at a reduced cost, please contact me as soon as possible and I will place the order.

 

So i don't know if they think the frame has been hit at that spot or whether the head transferred the force. No, i don't want another Sewanee because i don't know what to do different when i ride to prevent this happening again.

 

The attached Merlin's dent appeared to have been made by a Neanderthal - as though a straight bar had been put against the frame and then struck with a hammer - the dent was not perpendicular to the frame and the outside edges were very sharp. i have attached the 'after' pic - Litespeed measured the head and concluded that 0.5mm eccentricity indicated a heavy impact on the head, sufficient to cause the crack damage and consequently would not repair under warranty. This is just poor thinking - cracks are formed under tension and there is no additional damage to the frame. The cracks have formed as a result of alternating stress caused by just riding the bike - my mate is a heavy guy - about 85kg - but not a hard rider - no DH, no risky dropoffs, etc. Litespeed offered to repair the frame at my mate's cost - he accepted. The downtube was replaced and given a dent again - this time a little 'neater' - more like mine. He rides around very cautiously now.

post-19811-0-50066600-1298294660.jpg

Posted

Thanks for all the feedback Lagosloonie.

 

My (reasoned) opinion at this point is that it's a design flaw which has caused a failure via a much smaller impact than which would usually be required to do similar damage. As Chickenrun4me has noted, frames usually "buckle" in this spot when confronted by a serious head-on impact to the fork. In thise case however, the impact may not have been all that serious, it was just enough due the weakened structure caused by the design.

 

That's my opinion.

Posted (edited)

I cant understand why they would violate the structural integrity of the tube and structure by putting a dent in it there. What for? even if you follow the path of the wheel up, the contact point would not be there.

 

My intuition says that the structure is weakened by that dent in the round down tube. Do an experiment (even just a thought experiment): take a coke tin. Holding each end try bend it. Yes can be done but now imagine putting a dent in the middle, and how much easier it would be to bend and destroy

 

Perhaps its some batch manufacturing or shipping problem they are trying to pass off to the 3rd world.

Edited by kosmonooit
Posted

@Edman: Would like to hear how you would manufacture said tube from titanium? Serious question, no sarcasm.

I don't actually know, though I recall reading that you can use similar metal forming processes on Ti as you do on steel.

Posted

I don't actually know, though I recall reading that you can use similar metal forming processes on Ti as you do on steel.

 

Not as far as I know, Ti is still a bugger to work with, hence the exceptionally clean lines of Ti bikes. I see Lynskey have basically twisted a standard extrusion and threw their whole marketing dept behind it to spice things up, but that is about it in terms of having fancy tubes.

Posted

Not as far as I know, Ti is still a bugger to work with, hence the exceptionally clean lines of Ti bikes. I see Lynskey have basically twisted a standard extrusion and threw their whole marketing dept behind it to spice things up, but that is about it in terms of having fancy tubes.

You don't really see fancy steel tube either. It's really only soft aluminium where they can use processes like hydroforming to get the creative shapes. The real bugger with Ti is making the stuff in the first place and then welding it. It seems fairly tolerant of other manufacturing processes.

Posted

Thought that too, until I saw those steel track frames for sale on here that look just like hydroformed aluminium. (http://www.thehubsa....rames-for-sale/)

The seller's assertions aside, I don't think those are steel frames. The only other place I found one after some Googling was here: http://brakelesshk.bigcartel.com/product/yhc-908-limited-edition-time-trial-frame - says it's aluminium, and a forum that says they are copies of VISP frames which are also aluminium.

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