Doug64

Has anyone experienced a frame cracking like this one? The crack is in the top tube where it attaches to the Head tube.



I was prepping it for a month long tour starting next week, when I noticed the crack. It is a 2007 Bianchi Volpe, steel frame.

FBinNY 

Never in the top tube, but I've seen similar linear splits in chainstays. If Bianchi offers a long frame warranty, this qualifies as a defect.

If it were elsewhere in the frame, I'd say ride and watch it. But I'm more finicky about the front end of the bike, and while I doubt it's about to fail tomorrow, and might not for a year, I wouldn't stat an extended tour on this frame.

In any case the crack is probably along the seam of a welded and drawn tube.

ofgit

Could probably just stop drill it to relieve the stress and never have a problem.

korbjonathan

never seen one on a top tube like that but just had a seat stay on a trek superfly that was a crazy crack nobody around here has seen

JohnDThompson 

+1 this. If the OP is the original owner, pursue warranty replacement.

rebel1916

That's why I refuse to mess with steel. It's far too fragile.

dwmckee

More fragile than carbon? My wife toasted a carbon chainstay on her bike when she bumped it on something pointy while loading on a bike rack. I would definitely call this a manufacturing flaw and not caused by rough handling.

rebel1916

Steel can break when you are JRA. Especially these high zoot, thin walled modern steel tubes. It's just not worth the risk.

dwmckee

Do you think it is just the very high end real thin walled steel that is not very durable? We have 2 carbon bikes and several steel ones (Reynolds 725) and I have to say that at least from my experience the carbon frames, while wonderfully light seem to be far easier to damage in day to day handling than our steel frames.

rebel1916

Well yeah, those ones are the worst. I am willing to concede that a boat anchor like a Varsity would be durable.

Matariki

I'd be interested in how you measure durability and fragility of tubing. Please enlighten.

rebel1916

I already told you. These super thin walled, ultra light tube sets are the most dangerous. Anyone trusting their life to such things must be crazy. I'm not saying that steel can't be safe, I'm just saying that a lot of this modern steel really pushes the limits, and it's not worth taking your life in your hands to save a little weight.

Sixty Fiver

I am not sure what tubeset the 2007 Volpe was built on... they used Tange Infinity and Reynolds 520 which are both the same 4130 chromoly.

The crack does look like a tube defect along a seam which is pretty rare.

Torchy McFlux

I'd respect your point of view if you weren't completely wrong.
The thinness of lightweight steel can be shocking (0.5mm in the middle of a toptube, for example) but the characteristics of steel make it more fatigue-resistant than aluminum, and more capable of being damaged and still used compared to aluminum or carbon fiber. It doesn't "break when you are JRA". Sounds like you've been fed a line by a salesperson.

rebel1916

I have personally seen such top tubes get severely dented just from falling over. And they can't be easily repaired like CF. Leaving aside the risk to your health, the risk to your pocketbook is just too high.

Torchy McFlux

And I've personally repaired severely dented steel tubes and had them last for more than a decade of further use. CF is not "easily repaired". Once again, it sounds like you've been fed a line by a salesperson.

noglider 

OK, go right on believing that.

JohnDThompson 

You forgot the <sarcasm> tags.

Unlike carbon fiber or aluminum, steel does not generally fail catastrophically, or without ample warning.

JohnDThompson 

And unlike carbon fiber, they usually don't need to be repaired, except for cosmetic concerns.

rebel1916

Maybe 1 welder in 100 is qualified to work on such tubes. And CF is easily repaired and more and more businesses are offering the service.
Carbon Fiber Bike Frame Repair
https://calfeedesign.com/repair/
Carbon Fiber Bike Frame Repair | Appleman Bicycles
Not to mention all the DIY CF repair kits.

The message is clear. The safe and frugal choice is carbon.

Torchy McFlux

Matariki

It seems clear that you have a strong opinion about this. Give us a chance to consider your stance by providing some objective data that supports it.

Wilfred Laurier

it is clear to me
rebel is just trolling but
you are mistaken

steel can be made more fatigue resistant
but just because it can
doesnt mean it is

super lightweight and thin wall tubing
unless used by a lightweight and thin rider
or otherwise used in a low stress application
is often more susceptible to fatigue

a medium weight steel frame will probably last several lifetimes of normal use
but lightweight steel can easily be stressed beyond its design limit
and early failures were common
when lightweight steel bikes were more common

dwmckee

I do not mean to take sides on this but like I said above, my wife toasted a CF chainstay just by bumping it on a sharp corner while loading on to a bike rack. My wife's bike is a very typical late model Jamis, nothing built to the margin, just a typical CA frame. I do not get the blanket statement that all steel bikes are fragile. These lightweight steel frames are maybe half a percent of the steel frames out there.



And if one in a hundred welders can work on thin wall tubes, there are 780,000 licensed welders in the US leaving 7,800 competent welders to select among. That is quite a lot more than the three CF repair shops cited above. By the way, what do you think Calfee is charging for a repair these days. I have seen frame shops charge less than $150 to replace a top tube.

rebel1916

Au contraire mon frere. I can't possibly imagine that any steel riding denizen of BF, would consider the vigorous staking out of a strongly held position, supported by a mixture a facts and beliefs and alarmism, regarding frame materials to be trolling.