jfranci3

I really doubt you cracked the frame. Maybe some paint on the seat stay. You might need a new front derailleur mount, derailleur hanger, FD, RD, Chain, and cables. What gear were you in? If low, it's possible it's the bike shops fault, as the rear derailleur could have it the wheel spoke.

blakcloud

I get you don't want to read the whole thread but at least pay attention to the original post.

First Jungleland said he ran over a stick. How can this be the bike shop's fault? Second the LBS who actually looked at the frame believes the frame is cracked and I think that has more validity than your guessing it didn't crack the frame.

Sorry this happened to you Jungleland.

The whole thing boils down to crap happens, unfortunately this crap happened to Jungleland. It can all be fixed but it is an expense that will hurt and the time that it will take to have it sorted out doesn't help.

jfranci3

1) I don't see the stick. He didn't' actually see the stick while riding. I don't see any bent spokes. I'm suspecting he's not sure it was actually the stick. I had a derailleur get pulled into my spokes once, and it was exactly like a stick hitting them. I only mentioned the shop because thats just one of many possibilities.
2) I don't see a picture of any frame damage other than the braze on. I'm thinking some folks are just overly cautious....the LBS in this case. The seatstays and chainstays are pretty tough, everything else there is designed to fail before the frame. They mentioned the downtube crack, which would be very odd. Maybe the frame had a pre-existing condition.

blakcloud

What ever makes you sleep at night. I have more faith in the OP's version of events and the LBS's than your wild conjectures.

Cyclist0108

It is absolutely impossible to say anything one way or the other without a power meter.

nomadmax 

There is absolutely NOTHING as entertaining as a Bike Forums crash reconstruction thread There can't be any "structural engineer" positions open in the USA given the number of people on the internet working in the trade.

WhyFi

This would have earned you more credit if a) you hadn't already responded to the question and b) it hadn't taken you 16+ hours to come up with something "snappy." But kudos on the effort.

Jungleland

That's an interesting thought that it wasn't a stick and completely plausible. Everything happened so damned fast, I am sure my brain went to, what I thought, was the most likely scenario (never knew a derailleur could get pulled into the spokes).

blakcloud

A shifter doesn't magically get pulled into spokes for no reason. It gets pulled into the spokes WHILE SHIFTING. If you were shifting to the largest cog, and the derailleur limit screws are off or the the hanger is bent then there is the possibility of the derailleur hitting the spokes and being pulled. This can only happen while shifting. Again you would have been in the second to last cog, shifted to the largest and then bang. All this would have happened at the same time, you would have noticed. Were you shifting when it happened?

In the end you have taken the bike to the Trek dealership and they are pushing for you which is good. There are other solutions but I wouldn't go there until I had to. Good luck, I hope it works out for you.

znomit

At 20mph.

noodle soup

The forum is more enjoyable when you don't see his comments.

#ignore

jfriesne

Note that pros are concerned about performance above all considerations, in particular they prioritize performance over the potential cost of replacing a damaged bike with a new one. Money is no object when you're going for the gold, eh?

The rest of us, not so much.

dmorge

Same thing happened to me with a twig on the side of the road that i drove over. The rear derailleur broke, the chain broke, one spoke broke. The steel mountain bike was fine after repairs.

drewguy

Did the bike come without the "dork disk" installed? Had it been, the RD might have bounced off the dork disk instead of lodging in the spokes, avoiding much of the damage. Just sayin'.

noodle soup

you have an awful lot of faith in the dork disc.

I build over 150 bikes a month, and about 20% of them have dork discs that didn’t make it through shipping.
The bike is fine otherwise, and the box shows no signs of rough treatment. If the dork disc is this fragile, what make you think it will actually keep the bike from getting damaged?

strangdang

I worked at a shop during the original mountain bike boom of the 1980's. Bikes didn't have replaceable derailleur hangers back then. We were constantly bending the tabs back oh so gently from sticks in the der. Sometimes they would crack and we would have to have the local frame builder put in a new dropout. Which is now the reason why all mountain bikes have replaceable tabs now. Not as common on the road, but stick in the der is always a bad thing.

delbiker1 

So much needless conjecture about an event that even the OP is not sure what happened. Whatever occurred, that is tough luck and a sad way to start with a new bike. The bike shop should be advocating for you. Personally, I would not leave it up to just the bike shop. I would be contacting Trek myself, in addition. I hope the OP has an end result that is satisfactory to them.

Steeler_fanatic

This was one of my thoughts. Occasionally I think about removing the guard between the cassette and the wheel but then think about the implications and leave it in place.

Duragrouch

OP: I am sympathetic. However:
- This is why a local bike shop here recommends against anything carbon fiber, frame or components, for consumer bikes that are not raced at a competitive level. They are fragile and difficult to repair, but mostly fragile, other frame materials probably would have shrugged this off. Carbon fiber itself is very strong but is contained in a plastic matrix and there is good "global" strength and stiffness, but thin wall thickness, which adds up to poor "local" strength and stiffness.
- "Ruined" rear wheel? If there is a bad kink in the rim, either radially or laterally, yes. A small amount of lateral runout without a bend in the rim itself may be a result of spoke stretching alone, and if no damage to the rim or hub, may be corrected with a good retrue. Optimally, bring all the spokes down to zero tension, then slowly back up to tension by first cranking the exact same number of turns on each spoke. Those that take a lot more turns to tension up may be stretched too much and should be replaced. You can also totally unlace the wheel and measure the spokes but that is a lot more effort.
- By the way, this is why bikes have a "dork disc" between the cluster and spokes, to prevent the derailleur alone from doing this damage with no sticks. You should put yours back on or buy one. The clear plastic ones are not very noticeable. Yeah, I used to pull mine off too, until I realized why it is there and then put it back on to all my bikes.

Like you said, difficult to see the damage to the frame. Could you tell us where or highlight the areas?

zatopek

Yowee, having your new Domane wrecked like that! I once had a similar incident in which the metal wire/rod of one of those landscape flags, that was lying flat on the road, popped up when my front tire rolled over it. Got pulled into my rear derailleur which seized, bending the hell out of the integrated derailleur hanger on my steel Coppi (sweet ride), trashing the derailleur and sawing through a number of spokes on the rear wheel. Rebuilt the wheel, got a shop to realign the derailleur hanger, slapped on a new derailleur and she was back in business. I can see how the same incident on a CF fame might have ended much worse. Good luck getting yours fixed/replaced.

ckindt

So you drove your mountain bike over a twig and your frame was ok because it was steel?

Sy Reene

mscir

Situations like this make me think the same way. I'm considering getting a road bike for a nice 29 mi. ride I do with 2 good hills, I have a Specialized Stumpjumper with road tires on it, and fantasize about riding a lighter bike, stories like this make me nervous about CF. Sorry for the OPs troubles.

Cyclist0108

I ride steel.

However, I think this is a freak accident, and not something to use to dismiss carbon fiber.

I screwed up trimming some carbon fiber mountain bars, and eventually decided to toss the handlebars. To prevent someone dumpster-diving them, I decided to break it up with a sledge hammer, one I use with a steel wedge for splitting hardwoods, like madrone and oak. I was unable to damage the bars at all, despite repeatedly slamming them with the sledge. I wound up having to saw it in half (which is murder on hacksaw blades, too, btw).

mscir

The tech is truly impressive. I saw a video on how a carbon fiber frame was made and it's truly amazing how strong it is. Thanks for an interesting post.