So It Looks Like I've Been Rubbed Up The Wrong Way....

[redefined_cycles]

I've contacted whisky to see if they advise me to stop riding them.

Its quite noticeable to the feel. I'll certainly be checking for this type of thing more often now. I just rode and forgot about them.

Tut tut

Do you mean, noticeable to the feel that the gash can be felt when running you fingers over... or do you mean you have been pressing down and it feels ever so slightly mushy. If the latter then I'd definitely say (stop doing the squishing thing) and contact one of the repair specialists in case they feel it's repaireable..

[Rapidrob95]

Yeah if you can feel a difference to the ride or stiffness then I'd be getting off the bike and walking Quite like the idea of keeping my front teeth, but you may have different priorities

[Alpinum]

I just sent him your photo with a few questions,

So... he's being a bit of a dick.
He simply wrote back to ride it or bin it. He doesn't repair forks (I didn't ask him for that).
When I asked if repairs would be rather easy, he responded with "easy is relative", which I guess is a yes.

Sorry, not much of a help here.

[Alpinum]

Yeah if you can feel a difference to the ride or stiffness then I'd be getting off the bike and walking Quite like the idea of keeping my front teeth, but you may have different priorities

I've ridden home twice with cracked chain stay yokes. Carefully and on easy single tracks. I had crashed and testing the bike I couldn't cause it to budge under regular forces.
Once the rear wheel was removed it was all soft and crackling.

I've ridden hard in precipitous places with a damaged carbon rim and snapped spokes after running the wheel through some tests. Back at home I ordered the crash replacement and called my mate Mäse.
I stuck a children's plaster over the damaged area and wondered if I should've chose the plaster with the monkeys or the giraffes. Next day I was off hammering the bike again in the Alps.

I know, structurally those are very different situations, I'm just trying to show that carbon can take some damage before weaking to a point where riding in no case should be adviced.


In this case I completely with you though. Well worth doing some stoppies on a soft surface at low speeds and try to sense a wobbly feel and look for movement and listen for cracking noises.

From there on I guess it's a totally personal decision if one can accept the situation or not. One may be comfy with the amount of risk involved and others may shake their heads at it.
I for myself would take the risk.

[fatbikephil]

Definitely try and measure the total section loss and only bin if its more than 25% as this still leaves you with a 75% safety factor. Seriously this isn't bull, its engineering. I'd bet its less than a mm loss and as noted above, carbon forks are usually solid around the crown. Plus the worn bit is a nice smooth area, not a hard edged scratch or crack.

Next time you cross an old railway bridge bear in mind that its steel work (or worse iron work) will be up to 50% weaker than it was originally due to corrosion. Thanks to large safety factors such structures are still safe (well its a bit more complicated than that but you know what I mean). Then think of the consequences of such a structure failing - the engineers who assess such things do too.

[ledburner]

what caused the rubbing bag strap..?
(apoligies it it was mentioned earlier)

[Escape Goat]

It's noticeable to the touch. Nice little dip in it. Feels very smooth.

That's interesting about the bridge, I never knew that at all.

It was a bag, left to its own device that caused this.

[sean_iow]

carbon forks are usually solid around the crown.

My Travers Prongs are hollow there, looking inside it appears the steerer doesn't even go all the way through it, it blends into the sides.

Next time you cross an old railway bridge bear in mind that its steel work (or worse iron work) will be up to 50% weaker than it was originally due to corrosion. Thanks to large safety factors such structures are still safe (well its a bit more complicated than that but you know what I mean). Then think of the consequences of such a structure failing - the engineers who assess such things do too.

Next time you go over an old railway bridge bear in mind you weigh 100kg with your bike and not 100 tons like the steam locomotive did and so the 50% reduction in strength doesn't matter as you weigh 0.1% of what the engine did

[ledburner]

carbon forks are usually solid around the crown.

Next time you cross an old railway bridge bear in mind that its steel work (or worse iron work) will be up to 50% weaker than it was originally due to corrosion. Thanks to large safety factors such structures are still safe (well its a bit more complicated than that but you know what I mean). Then think of the consequences of such a structure failing - the engineers who assess such things do too.

Next time you go over an old railway bridge bear in mind you weigh 100kg with your bike and not 100 tons like the steam locomotive did and so the 50% reduction in strength doesn't matter as you weigh 0.1% of what the engine did

but if the bridge is corroding it will now be heavier but weaker, with all that extra oxygen .
I don't want to be that straw on the camels back
I may have an suitable anti rub solution for next time. fixed strap with floating attachment point replaces a standard strap. it allows forks rotation & no rub. for you, I'll do it at a cost (a few££ +postage) or postage & bearfodder.
PM me

[Alpinum]

Definitely try and measure the total section loss and only bin if its more than 25% as this still leaves you with a 75% safety factor.

Whut?
I must be misunderstanding this...
If a structure is, say, 10 mm thick originally (as your 100 %), and you sand it down to 7.5 mm, how can I have a safety margin of 7.5 mm when the structure needs eg at least 4 mm to be able to withstand a mechanical low limit?
In this example the safety margin would be 3.5 mm, not 7.5 mm (as taken from your 75 %).
Or put differently; if 10 mm are 100 %, 2.5 mm will be 25 %. A safety margin of 75 % would mean your structure would be non existent at a safety margin of 0 %. Yet clearly you need more than non existing material to be able to talk of a structure. Before I leap into quantum mechanics, I recall we're talking about a fork.

Also this is all assuming that the mechanical properties behave linear to thickness, which isn't alsways correct.

[fatbikephil]

Errm. If its lost 25% its 25% weaker. But it was originally designed with a safety factor of 2. It could be 3. But based on 2, if you lost 25% of its section then with a SF of 2 your still 75% in the green. Or is that the beer??

[FLV]

Any safety factor will be related to the stresses the fork can take. Thickness is irrelevant, especially in carbon.

[Leerowe76]

If its too expensive to have repaired by specailist you could always have a neat carbon loo roll holder

[Escape Goat]

It's certainly unfortunate that I've let this happen, but I've taken them off the bike for now.

Like everything, they're out of stock with no delivery date, but I guess that's just the way it goes.

Really appreciate everyone's thoughts on this, even yours Lee

[Leerowe76]

Target Composites in Northwich are very good check out their page mate, double fracture on the seat tube cost me £580 all paint matched and the work is top notch, maybe worth sending a photo over to see what they say

https://www.targetcomposites.co.uk/carbon-bike-repair

[slarge]

I think they’d make a cracking wheel building jig or something like that. Chalk it up to experience and buy a new pair would be my advice.

In my head if I have to ask the question then I already know the answer.....,

[Lazarus]

Thickness is irrelevant, especially in carbon.

So it could literally be one micron thick and be just as strong as something that was 3 metres thick?
I think its better to say thickness is not the only factor rather than its irrelevant as I know of no material that does not become stronger as it gets thicker

https://www.carbonfibresolutions.co.uk/repairs/

these are in southport so i think closer to you so possibly able to nip and let them have a look ? never used them so no comment on service etc

[Lazarus]

double post

[FLV]

Thickness is irrelevant, especially in carbon.

So it could literally be one micron thick and be just as strong as something that was 3 metres thick?
I think its better to say thickness is not the only factor rather than its irrelevant as I know of no material that does not become stronger as it gets thicker

In relation to safety factor designed into the fork, in this case, yes thickness is irrelevant to us discussing whether this fork can be ridden.

Knowing the amount worn through / material thickness reduction means nothing to us. The fork designers, yes they could make use of that information.

Its important to take information in the context in which it was offered.

[Escape Goat]

This just in from Whisky:

Stop riding them.


Bah.

[Cheeky Monkey]

Least Surprising news. Ever.

Sorry for your loss.

[Escape Goat]

[Alpinum]

This just in from Whisky:

Stop riding them.


Bah.

Yeah, better safe than sorry.

Sorry for your loss.

+1
Hope you get a replacement soon.
What are the specs of the Whisky?
If you can't get a replacement from them, perhaps the forum can help find similar forks.

[Escape Goat]

I love the A2c, rake and overall ride quality. Absolutely made up with them, so I'll get more later this year when money allows.

These will end up on the singlespeed as I only really potter around on that.