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ivanooze
12-20-2017, 11:56 PM
this past tuesday i went out to do some big ring intervals (53x12?) up a climb at 20-30 rpm

-every part of the bike was feeling great during the warmup but then... it happened

- as soon as i started pulling up on the bars for my 1st interval, i feel a sudden loosening of the bars. i stop to check what had happened.
- at first i thought the faceplate had loosened, causing the bars to swing up, but it wasn't that.

-next i checked the headset bolt, thinking that it had broken leaving it possible for the stem to slide off the steertube somehow, but... it wasn't that either.

- Next i thought, ok it must be the stem bolts that loosened causing the stem/bars to move out of their alignment. But of course, as you can tell from the title of this thread, that it wasn't the stem at all.

-Finally, i grab the bike by the stem and begin to move it up and down. From there i see where the base of the stem meets my headset spacer begin to open up.

- From here i thought 2 things.
1. I'm glad this didn't happen while descending and..
2. This is freaking awesome, i almost just pulled off a Hincapie.

-with all that being said, is it still safe to ride my bike despite having the steertube fail on me like that? I've ridden my fuji roubaix for 8 years now, and within those 8 years, it's been subject to rain rides, dirt rides, numerous crashes, and of course numerous amounts of mileage.

here's a few pics for your viewing pleasure
https://forums.thepaceline.net/attachment.php?attachmentid=1697951590&stc=1&d=1513832084

https://forums.thepaceline.net/attachment.php?attachmentid=1697951591&stc=1&d=1513832091

https://forums.thepaceline.net/attachment.php?attachmentid=1697951592&stc=1&d=1513832096

https://forums.thepaceline.net/attachment.php?attachmentid=1697951593&stc=1&d=1513832102

ivanooze
12-20-2017, 11:56 PM
and another one

https://forums.thepaceline.net/attachment.php?attachmentid=1697951594&stc=1&d=1513832193

FlashUNC
12-21-2017, 12:00 AM
Time for a new fork.

ivanooze
12-21-2017, 12:05 AM
Time for a new fork.

yeah i figured that much

fogrider
12-21-2017, 12:31 AM
what kind of crashes? usually the handlebars hits the ground...I guess we should check the steerertube closely.

oliver1850
12-21-2017, 12:53 AM
I'd check the frame over carefully for cracks. Finding none I wouldn't be afraid of it. We all should look things over more carefully and more often.

Kontact
12-21-2017, 12:54 AM
So, star washer hammered into a carbon steerer, rather than an expansion plug? Or is that an aluminum steerer? Sometimes older carbon looks chalky.

sales guy
12-21-2017, 01:03 AM
So, star washer hammered into a carbon steerer, rather than an expansion plug? Or is that an aluminum steerer? Sometimes older carbon looks chalky.

looks alloy to me.
but Cannondale did have star nuts in carbon steerers.

This is why I use 50mm long expanders on forks.

ivanooze
12-21-2017, 01:22 AM
So, star washer hammered into a carbon steerer, rather than an expansion plug? Or is that an aluminum steerer? Sometimes older carbon looks chalky.

come on give me some credit, i'm not just a pretty face, i got some set of brains (not much but enough) on me to realize i shouldn't put a star in a carbon steer. it's an aluminum steer/carbon fork

Kontact
12-21-2017, 01:27 AM
come on give me some credit, i'm not just a pretty face, i got some set of brains (not much but enough) on me to realize i shouldn't put a star in a carbon steer. it's an aluminum steer/carbon fork

I didn't know you installed it at all.

ivanooze
12-21-2017, 01:30 AM
what kind of crashes? usually the handlebars hits the ground...I guess we should check the steerertube closely.

hmmm let me make a list of the ones i remember.

1. hit a gigantic, hard as a rock pine cone that flipped me over while in a tight TTT formation. teammate didn't see it, so he dodged it rather quickly which didnt give me time to react.

2. crashed twice while racing, once in a crit, once in a road race.

3. Not sure if this would effect the fork in anyway but i've had multiple near crash experiences where i've had to hit the brakes extremely hard.

4. the bike was dropped by accident a few times on it's side

5. ridden on a bunch of crappy roads which im sure all of us have.

i'm sure there's more trauma that happened to this bike that i'm not remembering

ivanooze
12-21-2017, 01:32 AM
I didn't know you installed it at all.

i have done some cutting of the steer which inevitably forced me to push the star down lower. so that could've had something to do with why the steer failed. However, the crack was maybe 10-15 mm below where the star nut makes contact with the steer.

Louis
12-21-2017, 02:23 AM
-with all that being said, is it still safe to ride my bike despite having the steertube fail on me like that? I've ridden my fuji roubaix for 8 years now, and within those 8 years, it's been subject to rain rides, dirt rides, numerous crashes, and of course numerous amounts of mileage.

I think the frame itself is most probably fine.

If you're paranoid you might consider getting new handlebars, especially if they've been subjected to all the incidents you mention.

ivanooze
12-21-2017, 02:26 AM
I think the frame itself is most probably fine.

If you're paranoid you might consider getting new handlebars, especially if they've been subjected to all the incidents you mention.

well, over the 8 years i've done plenty of part swapping on the bike. the only original parts on the bike were the frame, fork, and seatpost. i've switched the bars out 3 times now and i believe i haven't crashed on this last set as well as the stem

Louis
12-21-2017, 02:32 AM
In that case, get a new fork and you're good.

Kontact
12-21-2017, 03:10 AM
i have done some cutting of the steer which inevitably forced me to push the star down lower. so that could've had something to do with why the steer failed. However, the crack was maybe 10-15 mm below where the star nut makes contact with the steer.

Yeah, if anything in the set up "caused" the failure, it was a lack of spacers to allow the steerer to flex over any sort of distance.

Not that that is a rule or anything.

Louis
12-21-2017, 03:23 AM
Yeah, if anything in the set up "caused" the failure, it was a lack of spacers to allow the steerer to flex over any sort of distance.

Not that that is a rule or anything.

I don't think adding spacers to allow "steerer tube flex" reduces the likelihood of fatigue failure over time. If anything, they'll make things worse.

http://sprecace.com/files/beam.1aa-1c.jpg

Kontact
12-21-2017, 03:44 AM
I don't think adding spacers to allow "steerer tube flex" reduces the likelihood of fatigue failure over time. If anything, they'll make things worse.

http://sprecace.com/files/beam.1aa-1c.jpg

If there weren't a broken steerer looking like a big ol' stress riser failure, I might agree with you. I just think it is possible that things are going to flex no matter what set up you have and it is better to not have all of it within a millimeter of a hardened, 90° stem edge.

Peter P.
12-21-2017, 05:55 AM
-with all that being said, is it still safe to ride my bike despite having the steertube fail on me like that?

You did a nice job on the methodical inspection after you suspected something was up.

I think your question was poorly worded but I'm not criticizing your grammar, just that your wording seems to ask if you can still ride the frame WITH the fork. I'm guessing you're asking if THE FRAME is still okay to ride.

Sure. Just because the fork failed doesn't mean the frame is close behind. Give it a close inspection-do the "coin tap" test for peace of mind, and I bet you find nothing wrong.

Insert snarky comment-Yet another reason to use steel forks. ;)

shovelhd
12-21-2017, 08:37 AM
Those low rpm climbing intervals are really hard on the front end. If there was a small crack, I could see where this would open it up. With all the crashes, I'd look the front end over really well, get a new fork, fit it properly, and enjoy the next phase of your bike's life.

oldpotatoe
12-21-2017, 08:46 AM
hmmm let me make a list of the ones i remember.

1. hit a gigantic, hard as a rock pine cone that flipped me over while in a tight TTT formation. teammate didn't see it, so he dodged it rather quickly which didnt give me time to react.

2. crashed twice while racing, once in a crit, once in a road race.

3. Not sure if this would effect the fork in anyway but i've had multiple near crash experiences where i've had to hit the brakes extremely hard.

4. the bike was dropped by accident a few times on it's side

5. ridden on a bunch of crappy roads which im sure all of us have.

i'm sure there's more trauma that happened to this bike that i'm not remembering

Ever clamp the seat tube in a work stand?? If so, I'm sure that's it..
:):eek:

Glad you survived it.I would be sure to contact the manufacturer..not for any kind of warranty but I would 'hope' they would want to know about it.

Blown Reek
12-21-2017, 09:11 AM
http://sprecace.com/files/beam.1aa-1c.jpg

https://i.imgflip.com/1f8as9.jpg
.

cmbicycles
12-21-2017, 09:36 AM
Why not just slam the stem and ride... what could go wrong? ;)
Noting that this frame is 8 years old, it is probably being deliberately slowed down by fuji, there will likely be a class action suit to confirm this theory. You are better off upgrading to the newest version to make sure it is 100% compatible with current roads.
I would definitely send pictures to Fuji, they may ask to see the fork to do some testing on it. If you are the original owner they may even cover replacement under warranty, depending on terms of warranty. Not the same, but, I had a 8yr old crockpot lid explode a couple weeks ago, manufacturer sent a prepaid label for the rest of the unit so they could test it... they sent us a new one too. It was way out of warranty in my case and I didn't expect a new one, but that was a nice gesture.

weisan
12-21-2017, 09:52 AM
Why not just slam the stem and ride... what could go wrong? ;)
Noting that this frame is 8 years old, it is probably being deliberately slowed down by fuji, there will likely be a class action suit to confirm this theory. You are better off upgrading to the newest version to make sure it is 100% compatible with current roads.

https://m.popkey.co/05e616/R5oL_f-maxage-0.gif

Ungaro
12-21-2017, 09:56 AM
You da beast! Crap....good enough reason for a new bike! Go for steel this time.

C40_guy
12-21-2017, 10:12 AM
Every so often, either before or after a ride, I wipe my C50 down with a damp cloth and then do a brief inspection, both visual and feel.

I run my fingers along all the tubes, joints, fork crown, etc. I tap the tubing with my fingernail, listening for a muted response where a tube or joint may be failing.

I also check my steel and aluminum frames...just not as often...

For bamboo, I'd just look under the bike for a telltale sign of sawdust piling up, suggesting termite infestation. :)

So far, so good. I'd rather find the early signs of a problem developing at home than experience it on the road.

oldpotatoe
12-21-2017, 10:58 AM
Every so often, either before or after a ride, I wipe my C50 down with a damp cloth and then do a brief inspection, both visual and feel.

I run my fingers along all the tubes, joints, fork crown, etc. I tap the tubing with my fingernail, listening for a muted response where a tube or joint may be failing.

I also check my steel and aluminum frames...just not as often...

For bamboo, I'd just look under the bike for a telltale sign of sawdust piling up, suggesting termite infestation. :)

So far, so good. I'd rather find the early signs of a problem developing at home than experience it on the road.

Or something like this...:eek:

old_fat_and_slow
12-21-2017, 01:17 PM
That looks pretty much like a standard fatigue failure. You have a fairly flat failure surface while the crack is initially propagating around the circumference of the steerer. Finally, after the crack has grown circumferentially around the steerer, there is insufficient cross-sectional material to withstand the normal tensile and bending operating stresses on your steerer tube, and you get the classic yield/plastic deformation that results in the sharp edges where plastic deformation and failure occurs.

Fatigue failures can be a result of manufacturing flaws that weren't caught by the fork maker when the steerer tube was manufactured. Tiny flaws in the material can cause stress risers that eventually initiate a crack over time. Then as the fork steerer is subjected to numerous stress cycles from riding, the crack propagates until it reaches the critical length and fails. In the aerospace industry, rigorous NDI is used to minimize this problem. In the bike industry... probably not so much.

Stress risers can result from damage due to mishandling or installation, or possibly even a crash.

I would suspect that this failure in no way impugns the integrity of the rest of your bike frame.

Glad you didn't get hurt.

dddd
12-21-2017, 06:25 PM
I had an aluminum handlebar separate in eerily similar fashion as this steerer, though adjacent to the stem clamp of course.

Same sort of history, with many years of hard use, race line sprint starts, and general CX pounding.

I had just descended a fast "gravity gulch" sort of cx course feature during one of a couple of practice/warmup laps, and immediately as I began ascending I felt what seemed like the fork had started to yield, something crooked, not sure why I assumed the fork. I immediately mellowed out and coasted to a stop, applying the brakes gently as I came to a stop, and just then the right side of the bar yielded completely and I was just left holding onto it with my right hand.

Luckily I had an old rigid mtb in my truck that allowed me to participate in the race that I had already paid for, and the day went well enough.

My handlebar was completely generic btw, and I guess that I should include that I weighed about 155-160lbs at the time.

ultraman6970
12-21-2017, 06:34 PM
Time for an extra ling expander, if it cracks the expander at least will keep the stuff together long enough to stop.

dddd
12-21-2017, 06:53 PM
Certain brands of vintage steel road bikes once came from the factory with a length of hardwood inside the lower end of the steer tube, for when the steer tube failed above the crown!

Perhaps a length of fitted balsa could be bonded into the upper end of a carbon steerer and also serve as a nut/anchor for the hold-down bolt?

I built up an older Cervelo aero frame recently where the carbon steer tube was lined with a thin aluminum tube, and with a star-fangled nut installed. It looked "factory" to me.

The steer tube was a little harder to cut and no doubt a good bit heavier than usual.

Jeff N.
12-21-2017, 07:38 PM
Wow...just wow.

DRietz
12-21-2017, 07:47 PM
I think this is a sign that you’re pulling too much while doing your big rigg workout - let your legs do the work!

Kontact
12-21-2017, 08:04 PM
In regards to my statement that the stem being all the way down without a spacer might have contributed to forming a stress riser, this is exactly what Trek cited in the 2010 Madone steerer tube failures:

http://cdn.velonews.com/wp-content/uploads/2010/06/BT10-ca_steerer_stem-0521-610x789.jpg

http://www.velonews.com/2010/06/news/carbon-steerer-breakages-treks-service-bulletin_121428