That’s real interesting.

Is your post a “just out of interest post”? or are you looking to determine the reason for failure for a warranty challenge?

I would be interested to know how old the forks are. If you have a good macro lens a close up of the fracture surfaces would be very useful to provide some clues as to the reason of the failure. when things like this happen, its always tempting to put the two pieces back together to see how they fit, however this can destroy some of the “evidence” which tells the tale of the failure.

Snapped fork steerer – anyone ever seen this happen?

once.

messiah – Member

Star fangled nut damage inside the aluminium steerer?

was the culprit – either that or just a total coincidence that the crack lined up with the star-nut.

Is your post a “just out of interest post”?

It was; I don’t know the person who owns the bike, I am just connected to his mate who posted the picture through another friend.

Nevertheless, your post has stimulated some discussion and also brought to light similar problems which others have had. Would be interesting to know just how many steerers are failing like this.

ahwiles has mentioned that that his star fangled nut was the culprit in his case. Sounds highly likely. Overtightening of these can put an indent into the inside of the steerer, this can serve as a crack initiation point and lead to this type of failure.

dday, the fork manufacturer said these need to be serviced annually, its the steerer tube ffs, what exactly do you service on a steerer tube. My belief is that the steerer simply failed. Its worth a check of the steerer every now and then IMO.

I could post the picture of my face but people will have just had lunch.

Big George wondering how he’s gonna tell Lance about breaking on of his bikes…

Too many pies ❓

ti_pin_man, you’ve been Paced by any chance?

northwind – – and the prize goes to … your good self

Sigh – looks like we all need 1’5 steerers now – where’s my credit card….

Some of us never gave up on the 1.5″ steerer… the industry will come back round to it in a while 😉

2005 Enduro Elite came with 145mm Nixons fitted

I’ve a set of forks with the steerer quite scored all the way round it , I was a bit concerned but it seems ok touch wood , its pretty thick steel but this makes me think 🙁

It’s definitely a sticker.

This happened to me with a set if manitou skarebs. I pulled a little jump over a log in Chopwell carpark while waiting for the rest of the lads to arrive and the steerer snapped. I bailed off (as you would). As I stood up very perplexed about what had just happened, one lad said he thought I was practicing falling off. Spoilt my ride that did.

If you have a good macro lens a close up of the fracture surfaces would be very useful to provide some clues as to the reason of the failure

Probably won’t be powerful enough to tell you anything useful, other than a possible initiation site, although people often identify the intiation site pretty much as far away from where it really was. We normally look at fracture surfaces with an optical microscope and then an SEM to find potential microstructural flaws that might lead to a failure.

Did he buy it from uk bike store?

nah, if he had, he wouldn’t have been riding it last weekend to snap it, as it would not have arrived yet.

What should we be torquing our steerer bolts up to then?
I always do it as tight as possible. Never understood why steerers and stems aren’t splined.

I’m not sure that it is established in fact that “overtightened” stem bolts or steerer bolts have caused this, so if I were you I would carry on using the manufacturers recommended settings.

ti_pin_man – Member

you were lucky. My alu steerer tube snapped 10mm up from the fork crown within the headtube, I have a false tooth and about 48 stitches because of this, about 25 inside my mouth and the rest on my face. Plus a hatred of a certain fork manufacturer.
He looked like this

His forks looked like this

Even his Oakley’s were from the new blood lens range

I’m finding a safer hobby.

Thanks mr overshoot for dragging up my old scars. I haven’t seen that picture for a while and it nearly put me off me dinner…

Bigjim – I’m still riding, gotta be done, cycling is just part of who I am, I guess we’re all the same otherwise we’d be on knittingtrackworld right now! Lol.

To be fair Joe ,you looked better after the accident tbf 😉

Seriously dudes.. I’m surprised none of you have got what caused it..!

It’s caused by bimetallic corrosion of the inside of the steerer due to intimate contact with the star nut.

The star nut scrapes the anodising away when it’s bashed in, and gets a fair amount of spray up from the wheel in winter, with lots of yummy salt. The steerer has eroded away from the inside. It’s the same with those pace forks. Look at how rusty that crown race seat is.

It’s best to take the top cap off occasionally and squirt some spray grease round there, or better still, never use a star nut in the first place on an aluminium steerer. Hope head doctors rule.

Go now and take your top cap off and have a look… You’ll be appalled at the state inside!

Well said Ti Pin Man. Myself I’m two clavicles, four vertebrae, one humerus, one wrist and multiple soft tissue injuries into my cycling odyssey.

It aluminium, the more you use it the weaker it gets and they look like old forks. Headset, starnut, spacer etc were probably more the straw that broke the camels back. loads on top and bottom of the tube will be high.
good effort sir…

Enough to make me swap my SFN’s to those long Ameoba headlock things. At least if it goes the bolt will holdit together.

I snapped a BMX stem once, landing a jump. Bars went forward leaving jagged stem that ripped in to my chest, face hit the tyre & rubbed along it for few secs. Tried to grab the fork legs to right my self but knuckles ended up skinned by Skyways. Managed to roll off sideways.
Not a good day. I looked a state. Managed to ride home no handed holding the severed bars.

Big George wondering how he’s gonna tell Lance about breaking on of his bikes…

True and dull story: I was sitting in a bar in Roubaix when that happened, watching on the telly, and Roger Hammond’s missus was there too, having wandered up the road, found the bar, and found us chatting in English. What I learned that day: Having a significant other racing in Paris Roubaix is a nerve wracking experience. When his teammate’s bike explodes, you go a very pale colour

I got what caused it. They werent that old when they snapped, maybe a couple of years old, but in the UK winters parts can quickly look scruffier quickly. My own ‘snap’ did happen some time ago and these are old pics. Not sure when the OP’s snap occured. Allegedly we should ‘service’ rigid forks annually… this really surprised me, everybody I rode with at the time (many on rigid SS) and all the road guys I’ve ever ridden with. I think a few nervous checks were performed by all afterwards. 😉

my next purchase after the snap was some ti forks. 🙂

Broken shivers by Alpine160, on Flickr

Old Shivers on friends bike a few years ago.
Cwn carn downhill track. Last run of the day. On the section where there are 3 steps a bit after the tunnel.