Highgear

It's really amazing the crap the industry comes up with. So now, would this be called a slow - release? I mean, is there good reason for this?

hueyhoolihan

i'll hold my judgement until i see what's on the other side, i guess.

Highgear

Think about it. Now you have to pull out the axle to get the wheel off.

hueyhoolihan

i edited my post...

i did think about it though and i don't know what's on the other side, but you do.

Highgear

Not sure. But I would guess a nut.

hueyhoolihan

so this isn't your bike?

Highgear

He'll no. I don't care for carbon or disc brakes.

hueyhoolihan

okay, let's start over.

i'll go first...

so why don't you think that's a QR skewer in there?

Highgear

Well, I have no doubt there is a cam mech. like a standard QR.

QUOTE=hueyhoolihan;16704861]okay, let's start over.

i'll go first...

so why don't you think that's a QR skewer in there?[/QUOTE]

Highgear

OK, I'll pick this conversation up in the AM. Time to do some gaming!

Andrew R Stewart 

It's hard to tell from that photo angle if the drop out is slotted or not. And I don't know the shapes of the DT (I think) "QR" levers well enough to ascertain from that detail. But there is some movement to the through axle spec on disk braked bikes, road and CX too. Fear of a brake force induced axle pull out of a slotted drop out. Don't know why a repositioned slot angle isn't seen as a solution. In the MtB world the added stiffness to a suspension fork (with the larger diameter axle/skewer and contact surface) of a through axle has it's merits. On a road bike the non suspension fork blades have less need for this. Andy.

cruiserhead

because it's a great solution for road disc brakes. Much more stiffness and stability without adding undue weight.
It cures the flex and rubbing of the rotor.

The quick release is a nice concept to bring it into road racing and standard road equipment where quickreleases are needed.
*it's not a traditional quick release. It's a quick release as you find in machine equipment, metal working rigs, etc

It's just further development for road disc.

Here's a link to more info about it. Focus version is the RAT system
I really think it will go hand in hand with disc as a future standard
https://velonews.competitor.com/2014/...u-axles_316278

well biked

Increased stiffness. That's what we're supposed to say. Increased stiffness.

And I don't doubt that it's true. But I also don't doubt that most riders, and most bike types, see no real benefit. And yet thru axles are here, have been for quite a few years in the mountain bike world, and they will continue to spread. Like crazy. To cyclocross bikes. Yes, even to road bikes.

And yes, it takes a little longer to remove and install a wheel with a thru axle than with a traditional QR wheel.

Increased stiffness. Increased strength. Progress. That's what we're supposed to say.

For anything other than downhill mountain bikes, freeride mountain bikes, okay, maybe "all-mountain bikes"............. I don't like thru axles. There, I said it.

YMMV.

cobba

Possibly because the disc brakes mounted on the rear of the fork put a downwards force on the axle.


Cotic made a fork with a front right mounted disc brake instead of the usual rear left mounted disc brake, they did this so there's a upwards force on the axle instead of a downwards force.

https://www.cotic.co.uk/geek/#ROADHOG_discmount

Retro Grouch 

I can tell you that I personally worked on a Specialized disc brake bike that would shed it's front wheel when the brake was applied so I know for sure that it really happens. My solution was to replace the house brand QR skewer which had an external cam with a Shimano skewer that had an internal mechanism so it would grip harder.

hueyhoolihan

well, okay, i see there's a problem with disk brakes and traditional dropouts that i was unaware of.

glad to see somebody is on top of it.

Andrew R Stewart 

As one who removes and reinstalls wheels daily I will say that faster is usually easier.

But the main point I'll make is the quest for stiffness and it's questionable need.

Back in the day better bikes were sold with "resiliency" as the star quality to the frame. The lower cost frames then were made of thick walled tubing that made their ride stiffer and less comfortable then the nice stuff. But these days to say such is a deal breaker. It's as though all the buying public are hard bodied 25 year olds. The only thing resilient thing about these targeted riders is their connective tissues.

This marketing ploy does work. On the relatively short (5-25 minutes) test ride that most all buyers do the negatives from a jarring ride don't become a problem and the sharper sensations make one feel faster.

But for the vast majority of buyers that i deal with a ride that's less tiring, more comfortable, that requires less focus on the task of steering is one that allows a longer and more enjoyable experience. I feel that the current fondo/endurance road bikes is the industry's response to the miss direction of trying to fit every road rider on bikes designed for professional racer needs. Yet the need to have "stiffness' still is present. Handle bars have OS or double OS center sections. Reduced spoke counts require far more rigid rims to keep from failing. Cranks and their BB designs trade off stiffness for flexibility of gearing choices (as though a low strength rider only needs a stiffer drivetrain to get up that hill).

As frames and forks got less compliant gel bar tape gets more common. Rigid wheels now have tires that can be run at "only" 100 psi (as in 25/28mm widths). Even decades old saddle designs with softer give (tensioned leather) are now the new cool.

But back to the question at hand. The "slow release" comes from the MtB world where flexible forks (remember that suspension is extreme flex in one axis, there's a certain irony here...) can't keep the reduced pad/rotor gaps (that disk brakes have) from rubbing. So a design that further braces the drop out/hub interface helps. In the road racing world the rider is followed by a support car. So their flat tire repair is more often now a bike exchange. Just watch in the future races with bike having disk brakes. The impressively fast wheel change (as the pack rides up the road) will be a thing of the past, instead a bike exchange will be the fix.

I don't know about you all but the pack I ride with stops and has a snack when I get a flat. And our support car isn't there. Just saying. Andy. (Who's about ranted out)

Homebrew01

So, if manufacturers set the dropout openings at the correct angle, regular QR would be ok ?

well biked

On current, higher end mountain bikes, rear wheel thru axles are about as common as front wheel thru axles.

Jeff Wills

Heck no. All they need to do is put the caliper in front, so the axle is forced into the dropout instead of out.

Andrew R Stewart 

Well the brake reaction forces would be directed against the sides of the drop out slot and not in the slot's open end direction. And if the user properly tightened the QR all could be good, as far as wheel retention goes. Note the qualifiers.

Still a concern will be the transfer of bending forces down the fork blade toward the drop out. the diameters/stiffnesses of traditional steel fork blades are challenged to resist these forces. Stories of unraking blades from disk brake use are about. So now you'll have stiffer blades, less comfort. And a new marketing plan to convince the riders that sore hands/shoulders are from poor fit.

Lastly there's the riders' using a wheel retention design properly to begin with. The lack of this is why there are so few kids bikes with QR wheels. New Jersey saw to that. The lack of this is why we have QR's that need an additional 6 (or so) turns of the skewer ends to clear the retention lips on the drop outs. I have to admit that i see as many (if not more) improperly secured Qrs these days as i did 30 years ago. Only now the springs are often on backwards keeping the wheels from at least seating fully...

Darn i got on another rant. Andy.

bradtx

Or moving the caliper to the front of the fork? Anyway, the problem of separating the axle from the drop outs has been known for over a decade. The through bolt is similar to what is found on a motorcycle and looks to be as good a cure as anything else. I like it, possibly because I have no money lost on a slow puncture repair.

Brad

cruiserhead

Front fork mount would rely solely on the threads of the bolt to hold the caliper. Every time you brake, it pulls at the threads.
Behind the fork, braking forces "push" the caliper into the fork. Correct?

RAT thru axles are minimally slower than quick releases... and if you include lawyer tabs, maybe it's a wash between them with speed of wheel changes.

Even though it's a whole new standard, I'm all for it.

Bill Kapaun

Just consider it a toolless release instead of QR.

cobba

I doubt that the bolts attaching the caliper would pull out.



Rim brakes on road bikes are only held in place by one bolt and nut.