EnsitMike

This is the seat tube of my SuperSix.

Fox Farm

Take it to your nearest Cannondale dealer and have them inspect it.

EnsitMike

I did, and the sales rep glanced at it and said it's fine. Didn't even take a look really-- just stood there and looked. I don't know if they try and avoid warranty claims or what… thought it was a bit odd.

catonec 

is it a scratch in the paint??

was there an incident like a crash, the bike falling over, or something heavy falling on the tube??

it would be unusual for the tube to split like that from just riding unless there was a major defect in the manufacturing of it.

thats the seat tube? I was told by my lbs that there is very little weight supported by that tube due to the diamond shape design of frames. and its just there to mount your front der and a water bottle to.

EnsitMike

No crashes or incidents and it is not a scratch. It is under the clear coat, although it is a bit hard to explain. I believe this bike has a matte clear coat of some sort because the mark can not be felt, but the seams of the carbon can be seen as well as things like this.

Zas

try and get a better photo, that one is no good

Fox Farm

And what did the sales rep who did not carefully examine the bike say that this was from? If it is under the clear coat, it could be delamination of the CF. Can you squeeze this area and have any deflection or sound?

BoSoxYacht

If you lightly tap the seat tube with a tire lever, does the sound change tone around the area in question?

BTW, have a trusted/competent mechanic take a look at it. A sales rep might not be the best person to ask.

dvdslw

I could be wrong but it looks like a surface scratch to me, it's uneven and goes against the grain, probably a transfer from whatever got up against it? Have you tried using anything to rub it out like a small dab of wax or acetone? If it turns out to be a "crack", contact Cannondale about it and bring the bike back in to the shop. If the 1st guy blows you off again, ask for the manager or find another Cannondale dealer. You paid good money for the bike that includes a frame warranty so use it! I believe the shop gets paid to transfer all of your components to a replacement frame so they should be willing to help.

DXchulo

The sound test is your best bet. The picture is difficult to see.

EnsitMike

and then here is a picture of the bottom of the downtube. This one had me less worried because it doesn't look like a crack but still thought I'd get an opinion.

OldsCOOL

I'd push for a claim on this. If under warranty, get on the phone. Whether it affects reliability is primary but you also have a bike with a tough resale value.

dudemanppl

LOL. I can see why he didn't look at it at all. Thats how carbon fiber looks like, dude.

EnsitMike

Tough when people are telling you completely opposite things

I just ride and admit to knowing nearly nothing about carbon.

glfguy8

+1 Looks pretty typical for an un-painted UD Carbon frame.

dudemanppl

Hey, we all gotta start somewhere. Better to be worried and ask than actually having it be an actual manufacturing defect and having the crabon asploding while descending at 45mph.

BoSoxYacht

Yeah, but why listen to people that actually know WTF they are talking about? It's much more entertaining to listen to hyperbole from forumites with months of cycling experience.

StanSeven

A tap test shows actual damage but it won't show something that has the potential to later weaken the material.

BoSoxYacht

It's either damaged, or it's not. A cosmetic scratch cannot transform into structural damage over time.

If a scratch gets worse over time, it was never simply a cosmetic scratch.

Looigi

Yep.

roadwarrior

The "sales rep" is not the person to determine this. Typically there is someone in service who will take a preliminary look and then get the company rep to look at it.

Whomever the knucklehead who looked at it was, well guess what? If it fails it is on you. Do you know who you talked to? That will also matter.

The photo is pretty bad. I can barely make out what it is. But if there is a hint of a frame issue, Cannondale looks at it in the shop.

roadwarrior

You don't "get on the phone" with Cannondale on warranty. It's done from the retailer. You have any idea how many knuckelheads are out there looking for new frames because they were "just riding along"?

roadwarrior

I have a suggestion. Do not get opinions on this from an anonymous forum. It looks to me like the seam for the tubing, but again, the photo is not too good. This is why you have a service person look at it and then they get Cannondale involved.

I love it when people advise to call the manufacturer, direct. That is the wrong thing to do.

BTW...I don't think I saw if you are the original owner?

CommuteCommando

It looks like a "seam". One possible defect that this could be is what is called "delamination". Once the frame is layed up in the mold, pressure is often applied to force the layers of CF against the outer surface of the mold. One of the things this does is force air out from between the layers. Tiny air pockets can start and propagate cracking between the layers. A defect like this leading to a fatal crash of an aircraft made by Russia's Sukhoy, led them to drop out of the civil aviation market when it was discovered that the cure temperature and pressure of the laminated wing spar was out of spec. on an entire lot.

It could be nothing more than cosmetic, but get it checked. The attitude of the sales rep sounds like some I have gotten at Performance Bikes, where I often get the "Ya want to super-size that?" treatment. Get an expert to look at it.

OldsCOOL

I would still be trying. There shouldnt be any dissatisfaction with a situation dealing with the main component of a bike. If it's a problem with topcoat, cool. If this is a crack or defective mold....time for satisfaction. CF isnt Alu or steel and certainly not in the same price range.