Carbon Fork for Cyclocross?
 

Dear Collective Wisdom (Dang, I love this forum...):

My interest in cyclocross grows and grows. But I am a Clyde at 225. I'm looking at a frameset with an optional carbon fork. Says the fork is for cyclocross. Is that true? Carbon on a 'cross? Just want to know if that's unusual or all kinds of common.

Much thanks!

Plenty of 'Cross forks out there made out of carbon. For the most part they are pretty beefy and pretty close in weight to that of a good steel fork, with the exception of high end forks like Easton, Reynolds and ALpha Q.

Don't forget yee olde 4ZA Python ...

Yes, they can be beefy, and that leads to mud clearance issues. I know a rider that had to stop (as in STOP) in a race to clear the mud build-up out of his fork (there goes the whole 'less weight makes you faster' argument). I'm tempted by lighter forks since I ride a Surly CC with a 2+ pound factory fork, but haven't seen one that screams "buy me". I also just like the look of the Surly CC fork, and the way it handles. So, what kinda bike you buyin'?

Kona put one on the JTS for 2007.

Which is why, at 225, I scrambled to get a 2006. Most folks will tell you that you'll be fine, and you almost certainly will. What worries me was less whether it would fail or not, but that small nicks can lead to "catastrophic failure". I have the kind of mind where I don't need too many stories to change my thinking -- biking for me aint fun if I'm worried about the gear. Each rider makes up his or her own mind on this. If you can live with the idea that there's a longshot chance that it might happen, odds are you'll be fine, especially if you make it a habit to inspect for nicks etc.

As for me, I was happy to go with the old project 2, suck up a little weight and put the idea of a fork failing out of my head and enjoy the downhills.

I've seen steel and alumnium forks break as well though!
There's always some degree of risk in this world.

Eric

Eric's right.

It's how they break that swayed me. When it breaks, carbon (and to a lesser extent alu) goes bang and fails (for me this cues images of broken teeth and / or collarbones). In my unscientific mind, steel will bend but is less likely to lead to a crash.

Of course the JTS has an aluminum frame, but there are like no stories of JTS frames failing that I've been able to find.

someone please show us a pic of a CF fork that has failed "catastrophically" in a race? Anyone?

Youll have that--
http://www.bikesportmichigan.com/fea...brokenfork.jpg

I think that you are looking for powder dusting out of the scratch.

They use CF Forks on tandems, my Las Cruces has a CF fork that rocks. I weigh in at 190 but routinely jump with this fork. There is one fork snapping hump on the locall single track that I try not to hit too agressively.

The SLC has a really beefy CF fork--
http://www.salsacycles.com/frames_06LasCruces.html

Err, I dunno. I see people at races rolling tires, sliding out on pavement and biting it hard, hitting obstacles and trees, all kinds of stuff. It's all catastrophic in a way. I have yet to see anyone break a fork. Switching to an Ouzo Pro saved me over 1lb on my JTS. I think it was worth it.

nah, sorry, not even a CX bike. Not really any information about the circumstances either. I've seen all manner of trashed forks but in every case I've seen they ran into something and I've yet to see a Cyclocross carbon fibre fork broken in action. I have seen cracked brake bosses and snapped steerer tubes related to improper stem mounting.

http://show.imagehosting.us/show/183...-1_1835921.jpg

Fork still looks good ;-)

The text claimed that this was due to a failure to do a pre race check. Not a CX race. Weird that both blades broke. But do you really need a picture to believe that this could happen? I'd rather have a failure in a sanctioned race any day over a non-race road failure.

Ok, so this was bugging me and I don't want to be the alarmist, so I looked at my notes from when I researched it a few months ago (yes, am a geek).

This is what originally made me widgy: http://ask.metafilter.com/mefi/46210

Not related to races, sanctioned or otherwise, but I don't like the idea of needing to inspect all the time, or switch out parts every year because it's been a year. the story of the bike-on-bike crash is telling. But again, that's me. It's my personal pychosis, and you may not share it.

It was enough to confirm my widginess, even if only web content...

^^ I am not sure that thread really covers the whole issue. Just because two bikes collide and the carbon one is destroyed is not a reasonable argument for fork design and material but rather the angles and forces that were applied during that given collision. I use both. Carbon on my pit bike and steel on my main ride. I believe in letting time tell. Carbon seems pretty strong so far. And if there ever is a real reason for weight weenie-ism it's in cross. When you have to lift a bike over and over through out a race a light bike makes a huge difference. Sure on the road you'd be better off loosing the love handles but in cross where you have to carry your equipment then 1 pound makes a huge difference. Plus I'd reccomend looking over your fork wether it's carbon, AL or steel on a regular basis especially if you crash it.

Two thoughts (somewhat unfinished):

1. I expect (at least) all the big producers of forks to have set their standards for the best way inbetween minimum weight and minimum risk of breaking * no matter what material they use. I expect them to have calculated that, and tested that. So it actually shouldn't matter if you buy a this years carbon or AL fork.

2. If carbon forks are scary, what about these light AL forks they build now (trying to compete with carbon in weight)?

I think carbon forks not only have you save some weight, but also gain some comfort (of which there is little in CX) in a way steel used to feel like (being a lot heavier though). I like AL for frames, but for the fork I'd go for CF anytime.
Eric

According to an article I've read Carbon is extremely capable of withstanding high pulling and pushing forces. It does not do well at absorbing a direct impact, such as a hammer blow ... or another bicycle... or low-lying branches. Sometimes cracks that are barely visible will result in a total and sudden failure later. That's why carbon parts are better used where they might be protected in the event of a crash. So that eliminates handlebars and seatposts, doesn't it?

So, if you've bought your fork new and are familiar with its history you might presume that you would also be aware of any direct impacts the fork has suffered.

Personally, after experiencing one endo at 30 mph I wish for as much security up front as I can possibly have.

does anyone know if the 2007 kona jake has an aluminum or steel fork? I am in the same situation.. I was looking for a fast trail bike as well as lightweight touring capable.. I like the JTS bike because it has better components but the carbon fork scares me a little bit.. I am also well over 200+..

In my catalog I see it's an Easton EC70X fork on the Kona JTS. If I get the meaning in the letters of Easton forks right it's the 'E' for Easton, the 'C' for Carbon and the 'X' for Cross. So then it would be a carbon fork (looks like one on the picture, too).

That's what they sell in Germany, don't know if the set-up is different in the US.


Addition: It also says it's a carbon fork in the catalog, I was just too slow reading it.

It's carbon w/ an aluminum steerer. I suppose you could always downgrade (probably for free) to the Kona Project 2 cromo fork.

I'm one of the partners at a shop and to give you a quick rundown of what we see spec'd on bikes these days:

- touring bike 1 - steel fork
- touring bike 2 - steel fork
- touring bike 3 - steel fork
- touring bike 4 - steel fork

- cross bike 1 - carbon fork
- cross bike 2 - carbon fork
- cross bike 3 - carbon fork
- cross bike 4 - carbon fork

I think the only way to get my hands on a cx bike w/ a steel fork would be to go with a small, esoteric company that specifically builds with "lightweight steel" in might or go with a larger company's inexpensive option. I haven't seen a weight restriction for any carbon fork we sell and most are warrantied (for cross use) for at least a couple of years.

Still, if you're a big guy and you don't trust it you'll ride faster on gear you're confident with. Get whatever will make you ride more - the end.

Well, I think the Jake is still the project 2, with the JTS now carbon. Shop should switch it out for you, or you could look for a 2006 (my LBS still has one (54, I think), but I'm on the other end of the country). I would think you would get that more than "free", probably get a credit along with it. FWIW, the project 2 has a good reputation for strength.

Bianchi wolpe is all steel, though not as dedicated a cross bike. I think that Jamis makes on that's steel, as does Lemond.