Tuesday, January 25, 2011

Discs On The Road? Disc-uss

If you're consistently bored enough to have read this blog for a year or more, you know that the deepest, darkest months of winter are when I start casting covetous eyes on other bikes that I have neither the space nor the money to procure. Luckily, the winter of 2010-2011 has been no different.

This year's "Thou Shalt Not Covet" award goes to the Salsa Vaya:

Now, I should disclaim right away that I haven't ridden a Vaya, and the folks at Salsa offered no bribes for a mention of their bike here. It's just an abstract longing of mine... nice, clean-looking road-biased do-everything bike, fat tire clearance, drop bars. Pretty much an off-the-shelf answer to my weird mountain/road mutt-bike cravings.

The discs give me pause, though. This is not the knee-jerk whining of a Luddite (for a change) -- I was still doing shop work when discs really hit the scene, and I got pretty comfortable servicing them. And I know the theoretical pros behind discs:
  • Riding in the grime? Your braking surface stays clean.
  • Wheel gone wonky? Your brakes don't care.
  • Braking surface on your rims? Don't need it. 

The problem on a road bike, though, is that no one's making (yet) an off-the-shelf drop-bar brake lever that can actuate a hydraulic disc. And in my extremely limited experience (just a little more than "squeezing levers on the shop floor"), I've been underwhelmed by cable-actuated road discs. Now maybe they just aren't set up right at the shops I visit (for shame, shops!) or maybe it's the "good squishy" that comes from a really powerful brake (the kind of squish that comes from all that power smashing the flexier parts of the system). Dunno. But I remain unimpressed by the feel and power compared to a good high-profile cantilever or even a basic Shimano V-brake. I'm also not 100% thrilled with the thought of a dished front wheel, but that could just be the paranoid ramblings of a lunatic.

I know I have readers who palp/run/rock discs on drop-bar bikes (lookin' at you, Local Steve) -- so convince me. Are they really all that and/or a bag of chips? Or are we looking at Biopace 2.0 here? And please phrase your answer in the form of a justification for me to get a Vaya if at all possible... because one brown bike in the garage is unusual, but two is a theme (or the smallest UPS fleet in the world).


Steve Fuller said...

My current brake line up

Canti - 1 (was two until the LHT was sold)
Dual Pivot Sidepull - 2
Hydraulic Disc - 1
Mechanical Disc - 3

Out of all of the types of brakes I own, I like the feel and stopping power of a well adjusted mechanical disc the most, especially on the Fargo and the La Cruz. Every set of mechanical discs that I've given a "test squeeze" to in a shop has felt too soft to me.

The amount of dish needed on your front wheel will depend on the hub that you use (and maybe your rim width and drilling?). For the SON hub based wheel I just built, the calculator allowed me to use the same length spokes for both sides. There's a bit of dish, but not a ton.

Of all the brakes I've used, the cantis on my LHT inspired the least amount of confidence to me, especially when the bike was loaded up. They were a a combination of short and either long or medium arm cantis. I know pads make a huge difference, and I was never fortunate enough to try out Kool Stops on that bike.

Steve Fuller said...

Forgot to add, of the bikes with mechanical discs, two of those use Avid BB7 "mountain" discs, and one uses Avid BB7 "road" disks with 105 "brifters". Really, the only difference between them is an adjustment for the pull rate. I've ridden bikes with the Avid BB5 and I've found those to be softer than I'd like, even when adjusted properly.

Scott Loveless said...

The bicycle industry is so busy stuffing its head up it's own ass reinventing the wheel, that they can't see the rest of the world has everything they need. There is absolutely no reason at all that someone, somewhere can't manufacture a master cylinder with a little screw to attach a brake cable. Maybe two screws - one for long pull, one for short. I swear to Thor the bike industry is run by inbred nincompoops who can do nothing but stare at their own navels. Gah.

Iowagriz said...

Nauman has a Vaya that you could test. Lives fairly close to you as well.

Steve Fuller said...

I'd be happy to bring over both a La Cruz and a Fargo as well. :)

Cavale said...

At the very beginning of bicycles braking was applied to the tire. But quickly engineers thought "isn't that totally weird and unefficient ?" and they invented rim braking. And then drumbrakes but they weren't powerful, light and simple enough so for a century rim brakes were the unquestionable way to go.

But we're in 2011 and it has now been a decade since disk brakes were successfully adapted to bikes. I personnally think that rim braking is weird and that disc braking is the next logical step, for the very reasons you mentioned.

According to dish, there's already the back wheel inflicted with that flaw so ...
I'm actually longing for the day when, as another logical evolution, some smart company will decide to widen the dropouts spacing (rear AND front) to avoid dish. But cost is the supreme judge ...