Stucky

Are you the same guy who was shilling for KTM a few weeks ago; or are you a different shill?

bt

that was his sock puppet Cntcasey

https://www.bikeforums.net/search.php?searchid=11177741

Stucky

Exactly. Either that, or the only two cyclists who appear to be obsessed with through-axles for roadbikes, both like to post links to a relatively unknown [to Americans] manufacturer.

And he forgot the "u" in "C_ntcasey".

(I may have been oblivious to the BD shills [Well, then again, I wasn't around, then] but this guy....!)

RJM

I would think thru axles would be worth it if one was to go with disk brakes....they are a pretty solid system of wheel retention. Not fast to switch a wheel, but thru axles make it easier to get the hub in square and keep the rotor tracking correctly.

The Trek Domane has thru axles on it's disk brake equipped models....I'm sure there is an engineering reason why.

bt

plus thru axles keep the wheel from popping out on a disc setup.

tumbalacasa

Doesn't the Specialized diverge also have thru-axles?

tumbalacasa

What do you think the engineering reason was as to why Trek Domane disc was built with thru axles, and why the Specialized Roubaix was not?

colnago62

Thru axel make more sense from an engineering standpoint. From a real word standpoint, you will have much less compatibility issues with a quick release. I feel like Specialized has a real world philosophy as a company, where Trek tends to push the innovation more.

Stucky

I remember when I got my first bike with quick-release levers.....it seemed so liberating, compared to axles with nuts. I'll stay with the QR's; Like rim brakes, they work fine; and accomplish what needs to be done in the simplest way. Seems like they're trying to turn road bikes into MTB's. If this keeps up, a few years from now, a road bike is going to weigh 30 lbs.

prathmann

Most disc brakes put a direct downward force on the front wheel when applied so it's more important to have secure wheel retention than on a bike with rim brakes. Recently one of our club riders had a bad crash when her front wheel came off her bike. The exact cause hasn't been established, but I suspect a combination of a quick release that hadn't been properly tightened and application of the disc brake on her bike. So, although a firmly attached quick release should be sufficient, I'd be in favor of the through-axle approach with disc brakes to minimize the chance of a serious injury crash resulting from foreseeable operator error.

hairnet

Because people use crappy ultra light skewers? I have never had an issue with QR on MTB with 160-203mm rotors. I just use a Shimano XT skewer. Not saying I'm against thru-axels.

tumbalacasa

I think you are right prathmann. I am pretty sure I want my next bike to have thru-axles and disc brakes.

Brian Ratliff

Thru axles are stupid. The problem is that the brake on the front fork is on the wrong side of the axle. The caliper needs to be ahead of the front wheel, on the front side of the fork. If this is done, then there won't be any issue with reaction forces from braking pulling the front wheel out of the dropout.

emveezee

A simple forward-facing dropout takes care of the wheel-ejecting-itself problem.

Dave Mayer

OK. I've figured out the latest sloping top tube fad on road bikes. A horizontal top tube is the most efficient design in terms of strength to weight. With a horizontal top tube, if a roadie wanted a more upright position, it only requires the addition of some spacers and and a riser stem to accomplish this. Someone mentioned 'stiffness', but to be clear, a riser stem has the same 'stiffness' and weight whether it is pointing up, or flipped and slammed down.

There are two reasons for the sloping top tube/high head tube fad on road bikes:

1. Ex-MTB riders expect it. Converts from MTB riding to the road are the biggest sales demographic for the industry. These new riders don't want to crush their junk. But unless they are falling off their bikes every few rides, a sloping top tube on a road bike is silly.

2. Weekend warrior road riders don't want to look like dorks. They want to look like their heros - the pros. Pros ride in a low aero position, hence they slam their stems. Your average Fred with a gut cannot emulate this low position. So they want a bike that superficially looks like a pro ride, with a negative rise, slammed stem. The taller head tube accomplishes this. Lengthening the frame head tube is about the heaviest and least efficient way to get this extra rise, but it is all about image and sales.

Fiery

Still not bothered by the fact that most pro riders ride sloping top tubes even though you claimed the opposite?

And let's do not forget your claim that there is a significant weight incrrease required to strengthen the seat tube cluster against the longer seat post, or your implicit claim that a head tube extended above a level top tube is for some reason lighter but no less stiff than having the top tube slop up to the top of the head tube.

You are an excellent example of starting with a conclusion and then trying to make the facts fit.

Psimet2001 

Meh -

My cross rig is 16 lbs with full hydraulic disc and thru axle fork.

Psimet2001 

...is there still an argument about "compact" vs "traditional" geometry? What year is this? Sweet geebus there's a lot more in life to worry about.

the sci guy 

i think it should be noted that until recently most MTBs had a straight top tube as well...

grolby

This is Dave's M.O. Trifling matters like "reality" and "expertise" make no impression on him. Arguing is mostly a waste of your time.

Fiery

@grolby, I haven't had the experience with him until now, I guess I'm still fascinated.

Stucky

How much did it cost? The average lower-level CF bike these days is quite overweight already- Maybe your uber-light bike of high-quality components can afford the extra weight, but that 21 lb. entry road bike bike doesn't need even more unnecessary weight.

bt

pics please

RJM

UCI to lift ban on disc brakes in August - VeloNews.com

badger1

Yep; another source: UCI announces summer disc brake testing in professional peloton | Cyclingnews.com

I should imagine that beginning 2016 ('17 latest) discs will be standard on most new non-t/t bikes from the majors, with (possibly?) a few rim brake frames still available. Good or bad thing pretty much moot at this point; done deal.