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Old 02-23-06, 11:33 AM   #1
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Aero Fork - disc brakes - non carbon ??

Is there such an animal as an aero fork which is not carbon and will accept disc brakes?

I haven't found one, and don't know if my searchs fail, or if there isn't such an animal.
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Old 02-23-06, 11:51 AM   #2
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By "aero fork" I assume you mean for a road bike. There are very few road forks set up to take disc brakes and all the ones I know about are intended for cyclocross and/or touring use so "aero" isn't an issue. Beyond that, even fewer are metal as carbon has prety much dominated the fork market recently.

If you really want one, a custom builder is likely your only choice.
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Old 02-23-06, 12:27 PM   #3
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Actually I mean for a tri bike. Concerned about carbon forks failing unexpectedly with cyclesdale weights.
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Old 02-23-06, 08:41 PM   #4
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Quote:
Originally Posted by HiYoSilver
Actually I mean for a tri bike. Concerned about carbon forks failing unexpectedly with cyclesdale weights.
Excuse me, a Tri bike IS a road bike. The alternative would be a mountain bike.

Carbon forks are exrremely strong and no maker I know of publishes a recommended weight limit.

As an aside, why on earth do you want to put disc brakes on a Tri bike? If any type of bike competition doesn't put high demands on brakes, its triathalon.
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Old 02-23-06, 09:10 PM   #5
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Originally Posted by HillRider
Carbon forks are exrremely strong and no maker I know of publishes a recommended weight limit.

True Temper (Alpha Q) has weight limits on a couple of their forks. The Sub 3 has a 225lb limit, for example.
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Old 02-23-06, 09:15 PM   #6
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Excuse me, a Tri bike IS a road bike. The alternative would be a mountain bike.
How 'bout an off-road triathlon? Just so you're aware of where the OP is coming from, the term "road bike" currently seems to be a rather widely accepted way of referring to a road-race bike. And the term "mountain bike" wouldn't seem to me to be a very good fit for a 'cross bike, even though 'cross races are primarily off-road.

But yeah, a disc brake on a tri bike doesn't make much sense to me either. It would definitely be less aero, for one thing.
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Old 02-23-06, 09:35 PM   #7
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How 'bout an off-road triathlon?
There is such a thing? Live and learn. Well, most of the time, when someone mentions a tri bike it's expected to be used on paved roads. Therefore, my comment.
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Old 02-23-06, 09:40 PM   #8
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There is such a thing? Live and learn. Well, most of the time, when someone mentions a tri bike it's expected to be used on paved roads. Therefore, my comment.
Yeah, I know. I just meant to call attention to the fact that most people associate the term "road bike" with a road-race bike. Neither term is perfectly descriptive, but they're pretty common jargon.
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Old 02-24-06, 09:14 AM   #9
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Excuse me, a Tri bike IS a road bike. The alternative would be a mountain bike.
Interesting. Most don't split bikes into one of two camps: road, mtn. Usually posters here talk about a wider variety of bikes: road, road-performance, road-sport, TT, Tri, cyclocross, hybrid, mtn, and bent. I may have missed one or two.



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As an aside, why on earth do you want to put disc brakes on a Tri bike? If any type of bike competition doesn't put high demands on brakes, its triathalon.
True, but the "tri" name is closest to the bike I want to get next. I won't actually tri, but looking for highest aero without going bent for good solo rides and able to easily handle long, steep, wet descents.
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Old 02-24-06, 09:19 AM   #10
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I was also interested in a bladed fork with a disk as well for a traffic riding build for the extra stopping power. I'm still looking but it doesn't look like many road forks are build to have the deceleration stresses at the bottom of the fork.
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Old 02-24-06, 10:23 AM   #11
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Really, there is no riding style in which you need both discs and the tiny aero advantage a bladed fork can provide. That's why nobody makes one (AFAIK).
Lugging around a big heavy disc brake on those hills pretty much cancels out any aero advantage you may get. I say, get a good road fork and keep your brakes in tiptop shape with good pads.
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Old 02-24-06, 10:30 AM   #12
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Not really looking for the areo advantage but hoping the extra material helps with the front to back stresses. Similiar to the areo deep v rim being choice for traffic riding.
Wanted the disk for stopping ommph in evil wet conditions.
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Old 02-24-06, 12:19 PM   #13
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Originally Posted by LóFarkas
Really, there is no riding style in which you need both discs and the tiny aero advantage a bladed fork can provide. That's why nobody makes one (AFAIK).
Function + form == cool.

Mechanically 30 gain is small, but aesthetically it looks dorky. Picture this nightmare a Cervelo P2C with standard cyclocross or mtn fork. Can you picture yourself on a sales floor trying to unload that monstrosity?



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Lugging around a big heavy disc brake on those hills pretty much cancels out any aero advantage you may get. I say, get a good road fork and keep your brakes in tiptop shape with good pads.
Heavy? 1 pound is what percent of total bike and rider weight? < 1% or < .5% not a big number unless you weight 50 lbs. Don't you lug around a helmet? safety in all riding conditions does cost something.
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Old 02-24-06, 12:49 PM   #14
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Weight on the bike is effin' different from weight on your effin' body for a bunch reasons. It matters a zillion times more. These comments and the "lose some of your own bodyweight" ones crack me up. (me= 6 foot 1 inch, 134 pounds) So 1 pound is a LOT.

Outta here.
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Old 02-24-06, 01:05 PM   #15
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Originally Posted by LóFarkas
Weight on the bike is effin' different from weight on your effin' body for a bunch reasons. It matters a zillion times more. These comments and the "lose some of your own bodyweight" ones crack me up. (me= 6 foot 1 inch, 134 pounds) So 1 pound is a LOT.
A zillion times. This does not sound like any math I know of.

The only difference in bike weigth and total vehicle weight is the rotational weight which will have an effect on acceleration but not on speed.

1 pound is a lot??? 134 rider with no gear + 17 lb bike is 151 lbs. One pound / 151 lbs == 0.6% It's the same weight as a 16oz bottle of water. I personally don't think a pint of bottled water weighs much.
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Old 02-24-06, 01:15 PM   #16
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Unless your a horrific weight weenie trying to hollow out TI parts with a dremel.
I carry a bag with me all the time so a couple pounds is nothing.
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Old 02-24-06, 01:47 PM   #17
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OK, I said outta here but I will come back once...
No, rotational weight is not the only consideration. All extra weight on the bike affects handling in corners, bunnyhopping, carrying the bike up staircases etc. Ok, no big deal so far. But it also affects acceleration and climbing. When you stand up on the pedals, your bodyweight is pressing down on the pedals, while the bike is "dead weight". See? So 1 pound is 1/20 of the weight of the bike, whereas the aero advantage of an aero fork is ... well, quite a bit less.

TRaffic Jammer is closer to right about what he wants and why, but if bladed forks were necessary or even useful for disc brakes, manufacturers would be making them. Also, notice the fact that it doesn't matter at all if you use a disc or a rim brake to achieve a certain deceleration from the point of view of flexing the fork. The brake stops the wheel, the road pushes back on the contact patch of the tire against your momentum... sort of. And, of course, you can't get "harder braking" on asphalt from a disc than from a good rim brake. A rim brake is easily enough to throw you over the bars if that's your fancy.
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Old 02-24-06, 01:58 PM   #18
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I'm concerned mostly about the roatation needed to clean the wet off the rim before good solid braking occurs. It's been quite sometime since rain braking on a roadbike for me, but I seem to remember at couple wheel rotation were needed before everything kicked in. Yes the brake stops the wheel, but the stress at the top of the fork is considerably more if the brake is mounted closer to the hub, no? The weight will "push" against the brakings' negative force and cause extra stress where the fork meets the head tube vs. the brake being mounted traditionally. Plus I think it would look kinda cool, on a pimped ride. Most of my riding is whizzing around in traffic and if I want to use my brakes and stop it's because I want to stop now. Not to control my speed but to come to a complete STOP. Oh why didn't I pay more attention in Physics class?
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Old 02-24-06, 04:06 PM   #19
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LoFarkas,
Finally understand why you are concerned about bike weight and I'm not. You stand and I only sit. That simple difference explains all the talk about percentage differences.

My problem is one of the things I like best about current bike is disc brakes. I want to move to a aero bike, i.e., Blade/Saber/Tiphoon/P2C/P3C/Aero-Ti, but these do not come with disc brakes. At least one manufacturer will custom the bike all to pieces but balks at disc's in the front where all the force is because of the concern that CF will not take the added stress and CF has a tendency to fail suddenly without some time of warning like other materials.

It's similar to what Zipp says about their wheels. They are ok with rim brakes because they don't stop suddenly, but with disc brakes the extra forces will pull the zipps apart. The al Hed 3 will probably be able to handle the disc brake forces, but I have not verified this yet.

For the wheels, I can replace the standard hub in Hed's alps with a disc hub and that would give me fair aero wheels with disc brakes. Hed says this is not recommended but should work and I should expect occassional spoke replacement. Now moving up from the wheels, next is the forks. Will they take the extra pressure. Thus my question. Does this make more sense?
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Old 02-24-06, 04:30 PM   #20
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With a carbon frame and the non-tested config, you could conceivably rip the whole front end apart in a panic stop. Now for a carbon fork some manu is going to have to create a carbon TT fork with disk mounts as well.
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Old 02-24-06, 04:41 PM   #21
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Originally Posted by HiYoSilver
Does this make more sense?
No, it doesn't. Aero parts just aren't designed for disc brakes.

If you want a very slightly more aerodynamic bike and a more forward riding position, get a tri bike. Upgrade the brake pads to either Kool-Stops or Swissstops for improved braking in the rain.

If you want disc brakes, get a bike (and components) designed for them.
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Old 02-24-06, 04:50 PM   #22
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Quote:
Originally Posted by TRaffic Jammer
Yes the brake stops the wheel, but the stress at the top of the fork is considerably more if the brake is mounted closer to the hub, no? The weight will "push" against the brakings' negative force and cause extra stress where the fork meets the head tube vs. the brake being mounted traditionally.
No, not at all. The forces between the legs of the fork and the steerer will be the same as long as the brakes are slowing the bike at the same rate, regardless of the design of the brake.
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Old 02-24-06, 04:53 PM   #23
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With a carbon frame and the non-tested config, you could conceivably rip the whole front end apart in a panic stop.
As if the bike were made of toilet paper or something...
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Old 02-24-06, 04:53 PM   #24
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Are you sure? Not paper...plastics......lol.. I was exaggerating somewhat. If the wheel manu doesn't think the wheel would hold up, that's enough of a colossal failure to me. I'm a child of aerospace, I get to see materials fail in big bad ways......it's fun. The early TI seat rails used to fail in a fun explody kinda way.

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