Friday Group Ride #142

The bike industry has this funny habit of trying to sell me things I’m not sure I need. It is all change, all the time, and the trick of it is that some of the change is good and some of it is just expensive. I think of myself as a discerning consumer, but my parts bin will testify to some imprudent consumption throughout the years. It happens.

This year there are a couple trends that have me puzzling.

The first one is 650b mountain bikes, and let me come right out and say, I own one. In fact, it’s the only mountain bike I own. And it’s a single-speed, which makes it a lot like a unicorn in the mountain bike universe where everyone seems to be on a dual-suspension 29r anymore.

The conventional wisdom on 650b (or 27.5 for those of you who want the world to make sense) is that it combines the best of 26″ wheels, the weight and handling, with the best of 29rs, obstacle clearance and rolling speed. The new (actually old) wheel size is even being raced at World Cup level, so if there is some kool-aid drinking going on, it is not limited to a bunch of engineers in the parking lot of a bike company. This thing is happening.

At Interbike, Ritchey even displayed a 650b bike Tom built for himself, and raced, in the ’70s, perhaps just to confirm things we already knew such as, everything old is new again, AND Tom Ritchey is cooler than you or me.

Well, let me tell you, I have ridden 650b, and I like it. I’m not such a trail shredder that I will attempt to communicate in technical terms why it does what people say it does, but I do like it, and coming from a 26″ bike, I think it makes sense for my limited riding style and general propensity for impracticality.

The other trend, and this one is bigger and I’ll wager more interesting to RKP readers, is disc brakes on road bikes. Everybody’s talking. The big builders are rumbling as though this is going to be their next thing, but there are only a few market entrants at the moment. Volagi makes the Liscio (and soon the Viaje) and Colnago makes the C59 disc. Lynskey just announced one. Canyon showed one at Eurobike. And there are others, but chances are you haven’t seen them on the road yet. All current models are running mechanical discs while we wait for a really good drop bar shifter that will support hydraulics.

This week’s FGR is technical and wonky. Are these two trends worth our time? Do you see the value to 650b trail bikes? Will you go disc on the road? Why? Why not? Have you ridden either one? Share your experience. If the future is now, are you going along for the ride?

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  1. Kenny McCarthy

    650b makes complete sense for a lot of riders. I’m 5’9″ and I found it rode better than the 26″ I’ve been riding for years. A 29er is simply too large, perhaps for those 6′ and over it would make complete sense.

    On the other hand, a road disc won’t be pratical because unlike a rim brake, a disc brake loads a tremendous amount of torque into a wheel. For that front wheel you’re going to need to beef up the rim mass, make the hub shell much more robust, and increase the spoke count. The weight penalty would negate any advantage a disc brake could have i.e. modulation. Pus, I suspect you could get significantly better modulation in a rim caliper/lever system by introducing hydraulic into the mix.

  2. A Stray Velo

    Yes, both are certainly worth our time. Besides who doesn’t like new things?

    650b is nice, but so are 29er’s. I’m predicting that 26″ wheels are out in 5-10 years. The choice is nice because for some terrain one may be better than the other.

    Disc brakes on road bikes are a interesting idea. To be honest I’d only want them on my bike that I ride in the “off-season” or that other part of the year when I don’t ride my nice bike. They only really peak my interest for bad weather conditions, other than that…I don’t see them as something I’m really want.

    Choice is nice and that is what I really like about new stuff…more choices.

  3. Q

    I haven’t done much off-road riding in a while because there are limited opportunities where I live now, so I sold my aging mountain bike last year. At some point in the future, I may buy a new one, and I expect it will be a 29er. Why? I’m tall (6’3″) and that seems like the natural wheel size for the size of frame I ride. All the technical arguments about handling and such are secondary considerations for riders at the edges of the size bell curve. I think it just makes sense to have different wheel size options for different frame sizes. Heck, when I look at the geometry of my wife’s road bike, sometimes I think maybe you could build a better road bike at that size if you used 26″ wheels. So, I’m all in favor of more size options, even if I’m not likely to use them.

    I’m also very interested in road disc brakes. I can’t say I have a good technical argument why I need them, though. I haven’t raced in years, so I don’t need the UCI’s blessing. I wouldn’t buy any of the current offerings. I’d like to see the technology progress a bit first.

  4. Doug Page

    I have a 29er and a 26er, and I like them both. The 29er has been a Godsend for my technical prowess. Even on my 26er I ride rock gardens now with more confidence than before I rode my 29er. Big wheels rock!
    As to disc road wheels, I think wheel designers will get creative with rim design now that there will be no brake track on the rim. I’m seeing carbon 29er disc wheelsets around 1500 grams now, and they are plenty strong. The braking/spoke issues have been pretty much worked out.
    In fact, I am waiting for a disc bike to buy carbon rims, because I am not ready to deal with the funky braking characteristics of today’s road carbon rim brakes, which,
    IMO, have led to particularly horrific crashes in recent races.

  5. mk

    Disc brakes on road bikes just seem like overkill. CX? I can see the benefit there. But not on asphalt – just don’t need that kind of power. All at the cost of heavier cross laced wheels, added complexity. Although at the added benefit of modulation & lower maintenance. Nice way to make most parts incompatible though.

    650B seems more interesting than 29″ at least where I ride. The downside is the bike industry is iterating so quickly, standards are multiplying. The cynic in me wants to point at sales vs. benefit. There are so many standards that almost nothing is standard anymore.

  6. TominAlbany

    I’m a father of two young (6/4) children and we agreed my wife would stay home with them at least til they’re in school.

    I have NOTHING new! My 13.5 year old Serotta with 9 speed ultegra is going to have to last me. I need to replace the tranny. Anyone know where I can find reasonably priced parts?

    My 11 year old Trek Fuel (9 speed) rim-brakes, full boing – old-fashioned 26″, non-tubeless wheels, is going to have to last me. It needs a tranny overhaul too. Same question on parts! Oh yeah, the fox shock for the rear triangle leaks.

    I’d love a sweet new road ride. I don’t need disks.
    I’d love a sweet new dirt ride. Would love 650b w/disk and tubeless.

    The beauty of our sport is, in itself, bicycling is a simple activity and the new is mostly style over substance. The main exceptions, IMO, disks and tubeless for dirt. My Ti Serotta will never break or wear out. I will never need a new road bike. Just replace parts – that is, until I can’t find quill stems anymore!

    Enough rant. Ride and send your Christmas wish list to your personal Santa Claus and get a new widget. I miss bike shopping but, until the $$$ change, I can make what I have work for at least 10 more years.

  7. SteveP

    Road disc is a solution in search of a problem. Maybe I’ll have a problem if I start riding mountain descents in the snow, but I’m not that lucky yet.

    650b is cool because tires are cool, and I’ll never tire of being a tire nerd/snob.

  8. SeanoSean

    Currently on a 26r with a 29r on order to be built up next year. @ 6’2″, the proportions of a 29r look to be about right and the weights have come down to make them reasonable. With that said, 650b makes a lot of sense for all the same reasons –

    As for disc brakes on the road – definitely a huge plus in the bad weather as well as ease of running carbon wheels (without the heat build up issues of carbon clinchers!). My carbon mtb wheel set comes in at 1285g and proves that you can have lightweight and durability built in to offset the slight increase in brakesets. I say, can’t wait!

  9. DJ

    Disk brakes save rims from getting destroyed at the brake surface. I live in a place where it rains over 160 days a year; I’ve gone through lots of rims. Also, disk brakes work better. Why not choose the design that is less scary. Finally, the idea that you don’t need lots of brake power on road bikes seems silly to me. The slick tire surface and smooth road makes it so it can take more stopping force before the tire locks up. Might as well have the ability to stop as fast as possible without using Hulk hand strength.

  10. Rspinnaking

    I didn’t want to believe in 650b. I wasn’t excited about another new standard or the poor selection of tires, rims, and forks available at the time. This all changed at the Interbike Dirt Demo 2 years ago when the 29er I was waiting to ride failed to return on time. The 650b evangelists at the Jamis tent rolled out a Dragon 650. “Just try it,” they said. After a full day spent riding 29ers of all materials, price points and handling styles the Reynolds 853 frame, slightly slack but playful geo and ‘tweener wheels just felt like home. For me, 650b truly is the best of both worlds. The wheels are large enough to add just a little extra stability, traction and roll-over ability but are still small enough to carve into little curves and pockets on the trail, rip berms and pump track, flick around trail obstacles and generally shred anything in their path. Now that the industry has delivered a whole new boatload of 650b-specific components, all of my previous objections are non-issues. I heartily encourage everyone to give 650b a try. Your experience may not be as revelatory as mine but there is a lot there to like.

    As for disc brakes on road bikes, I’m uninterested. It’s an interesting engineering exercise for bike makers and I can see a place for discs on an adventurous, all-weather, go-anywhere type of ‘cross or touring bike that might be on the fringes of the “road” category but don’t think the benefits outweigh the costs for any kind of skinny-tired, competition-driven bikes. The traditionalist in me won’t allow it and there are plenty of more practical issues in play as well, like the hefty chunk of added weight over a svelte set of cantis, mini-Vs or calipers. That weight isn’t just in the brakes themselves. It comes in the form of added material in the frame and fork, heavier wheels with rotor mounts and more spokes and all the freaky adaptor-majiggers currently needed to get hydraulic performance from mechanical levers. Add in the fact that all those nice sets of road and ‘cross wheels hanging in your garage would be rendered useless and you’ve got one ugly, expensive mess. You’ll never see me racing ‘cross on discs (unless the UCI does away with barriers and tire width restrictions and turns CX into short-track MTB) and I doubt we’ll see widespread adoption of disc brakes on skinny-tired road bikes for many years, if ever. At least I hope we don’t.

  11. Ransom

    I think what Q says about sizing wheels to go with the bike makes some sense… I haven’t ridden a 29er, and I could be ridiculously, stupidly wrong, but though I’m 6′ tall, my 26″ wheeled mountain bike feels unwieldy and whippy and rangy compared to my 24″ wheeled trials bike or my ‘cross bike. I’d spent some time off mountain bikes and seat time is helping, but the idea of significantly larger wheels kind of puts me off…

    Road discs: I’m curious to see what wheel manufacturers come up with in terms of rims, spokes, etc. I feel like it’s a better solution than providing a braking surface at the rim, but I also feel like it will take some thinking to come up with solutions for taking advantage of that outside of high-end carbon wheels. I wonder whether we’ll see larger hub flanges in order to align spokes better with braking forces. Bigger flanges = more weight, but if a similar amount can be removed from the rim, that’s still a big win.

    I wonder whether we might even see a whole new mode of rim production or materials with the need to brake removed from the rim. Chopped-carbon injection molded, or even plastic for more economical rims…

  12. Eric L.

    Disc brakes on a road bike. I am wondering if this is a potential solution for the issues with using carbon as a braking surface on clinchers. Padraig wrote recently about delamination of some wheels under heavy braking loads. With most of us not being supported by a team with spare wheels, tubulars are not practical. Moving to clinchers leaves the braking surface unsupported horizontally. Thus, a disc takes care of two problems by producing a more rigid wheel and pulling heat out of the wheel itself by not using it as a friction surface.

    A lot of effort has been put into making disks strong enough for off-road use. With all of the engineering that seems to be going on with road bikes, I bet that they can quickly figure out how to make it light.

    Maybe, just maybe, by separating the two, we will get carbon wheels that are both good and affordable. Then again, I hit my head once so it could just be mental problems.

  13. Gary

    The disc brake doesn’t attract me much. 2 applications on the road, with carbon rims, and for wet weather riding come to mind.

    I have a teammate/buddy in Portland,OR that I rode with plenty. He has a Ti rain bike with disc brakes. Seems like the disc was rubbing/hitting half the time, made some concerning noise when braking and required different wheelset.

    The carbon rim application makes theoretically more sense. The now-wellknown issues with melting clincher rims on descents would be eliminated as would wet weather and rims. No changing pads between aluminum and carbon rims.

    Whether these are convincing to the market place remains to be seen. Like electronic shifting, the mechanical method has worked pretty well for a very long time. Is that compeling?

  14. Champs

    All road bike braking power is limited to the traction of slick tires, so discs definitely won’t be too powerful. You can lock up the wheels with dual-pivots if you want.

    But I’ll be happy to never hear the screech of pads on carbon tracks or proclamations that *THESE* carbon wheels really do brake like alloy (and we mean it this time).

  15. WV Cycling

    Purchased a 2009 Gary Fisher Cobia my last year of undergrad. $1000 after discounts. 29er with X5 components, RockShox Tora front suspension, and heavy wheels, even at that price.

    Mountain bikes are easily pricing at $6000 for a full-susser these a days. I don’t have that kind of cash, but at 168cm tall with a 75cm inseam, no matter what I do, no matter what parts I attempt to replace for comfort, I do not like my mountain bike at all. ( I think Q-Factor on mountain bike versus road bike is a big part of this also. )

    This is a travesty. I live in West by God West Virginia. We have so much natural and untapped land, along with some of the best state park trails I’ve ever seen, but I have the hardest time enjoying it. I can’t place my finger on it either.

    Going down to a 650 wheelsize could potentially alleviate these problems, but that is a damned large investment for a person who doesn’t have that kind of cash right now. I keep telling myself if Betsy Shogren (160cm tall) and Emily Batty (155cm tall), why can’t I ride a 29’er? That and what if it isn’t the frame and tire-size, and there’s just some odd problem with me and mountain biking?

    It makes me feel like such an outcast living in West Virginia and not enjoying mountain biking, being very much like a Canadian who has no interest in hockey (stereotypes can be fun sometimes).

  16. Walt S

    There seems to be more innovation in the bicycle industry every year. Some of them are good and others have proven to be merely a relatively short lived fad. Does anyone remember Campy C Record Delta brakes or even the Cobalto with its “jeweled” center nut? The former was heavy, hard to adjust, and had inadequate stopping power. The latter was pretty, but no better than the brakes that preceded it. Today, like yesterday, we have the idea that the newest is actually better. Sometimes it is. But disc brakes on road bikes are inherently heavier. They may work better in certain applications like cross or touring, but with the currently available technology, I do not see an advantage for disc brakes on road bikes. Yet! I have an open mind about the supposed “improvements” coming down the pike in cycling, as well as being critical of whether it is something that improves the cycling experience or complicates it.
    The subject of wheel size in mountain biking is an interesting one. The choices that consumers make will determine ultimately which wheel size stays and which fade away. When I started road riding when dinosaurs still walked the earth, 27 inch wheels were found everywhere, with nary a 700C wheel to be found. When I needed a replacement wheel for my Gitane Tour de France, the quizzical looks I got when I went into a bike shop for a replacement 700C tire immediately told me the replacement was going to be harder to find than I thought. Now try to find a 27 inch tire. 26 inch, 27.5/650B, or 700C/29er, will all sort itself out eventually in the marketplace by what consumers buy.

  17. Rod Diaz

    I don’t do MTB, but I think it makes sense to have wheels proportional to the size of the individual – and their use. I don’t think BMX bikes will ever use 29ers 😉

    Disc brakes – I like the notion. I think they will enable better rims and wheels in general, since the braking surface is decoupled from tire-mounting duties. Especially for carbon rim applications, I think they make perfect sense. Having a couple of scary moments descending in the wet with carbon rims, I definitely think this aspect can be improved (and yeah, you can just use what it’s currently available. Square-taper BBs are still available, as well as coaster brakes and downtube shifters).

    I will definitely try them in my CX bike when they are a bit more developed, maybe when the “big” guys come up with a full, cohesive system.

  18. T. Guy

    As an occasional off road cyclist, I still ride an old hard tail Trek. I have no compelling reason to upgrade to 29 or 650B or full suspension. I just don’t do it enough to want a new bike, though if I had a new bike I might ride it a lot more. But I’m not shopping for one right now.

    I have a lot more to say re: disc brakes for road bikes. I have a Volagi Liscio. The Avid BB-7 brakes work great, I have more control and therefor more sure stopping power than any rim brakes, and I am usually on Shim. D-A. Though the brakes work fantastic, there are certain issues, mostly involving the exact spacing and alignment of the rotor in the caliper such that you need perfection in order to swap wheels. OK in the garage, but how could you do neutral support wheel swaps in a road race situation? And for an on the road wheel change where you can’t put the bike in a workstand the poor mechanic (or YOU) is/are risking slicing his hands as he works trying to hold bike steady to insert the wheel in the dropout.

    I have gone to carbon fiber rims to take advantage of the fact that there is no rim overheating or special brake shoes needed, and the result is better climbing on the lighter wheels, and using road tubeless, the ride is sublime.
    I ride a road tandem with discs and it is the solution to the problem of rim overheating and tire blow off on the big mountain descents.

    But the Volagi is my winter bike, and I did not buy it just for its’ disc brakes, I bought it for all round bad road and bad weather riding. The tandem is a special case. On my summer bike I see no need for disc brakes at least until they have evolved and perfected them from where they are today.

    Bottom line: disc brakes will remain a specialty niche for a while until the minor bugs are worked out.

  19. Andrew

    No opinion on MTB. I don’t really ride them these days. When I did, I was always perfectly happy with 26″ wheels.

    I just made the plunge for disc brakes on a gravel road bike (Salsa Warbird Ti). Why? Just because I wanted this cool new Ti bike (I’ve always lusted after a Ti bike) and they didn’t make it with cantis. Would I have bought the canti version if it was available? Yes- I’m a more aggressive descender than some, and I’ve never once wished that my cantis worked better. They’re fine. I imagine the disc brakes will be nice on wet days or in the snow or mud. I can’t imagine a reason why I’d want them on a regular road bike.

  20. DclDJ

    I’m with TominAlbany. I’ve got a great, albeit 2002, Look with a 9 speed group that I’m still trying to be worthy to ride. My annual cycling expenditures are limited to replacing what’s worn out.

    Will disk brakes make me a better rider? Will they increase my enjoyment? Probably not, and honestly (much to your sponsor’s chagrin), I don’t expect to find out any time soon.

  21. Anthony F

    Disc brakes will allow wheel manufacturers to move the weight from the rims to the hubs. Lighter rims will eliminate resistance to the use of slightly wider (heavier) tires. Such tires will result in increased traction and improved aerodynamics with the current crop of wide rims.

    I want the best stopping power available.

    I’m nudging 60mph coming down Mt. Baldy, I’d like to be nudging 70 or 80.

    Unfortunately, like in motorsports, how fast you go is limited by how well you can stop.

    I need the component and wheel companies to really get the road disc/ wheel thing going.

  22. Khal Spencer

    Bicycles should be elegant, simple, and somewhat resistant to forced obsolescence. The constant fiddling with parts and designs might be fine for top level racing funded by deep pockets, but when imposed on consumer product line, might not be so fine for Joe or Jane Sixpack, who has to feed a bike fix on a normal wage or salary. So in my view, it had better be a sea-change level of improvement if I have to start changing out all sorts of parts to adapt to a new standard such as 650c. As an everyday Fred, it ain’t gonna happen with me without a fight. I still run Shimano 9 speed and Campy 10 speed because if it ain’t broke, don’t fix it. The legs need to improve first.

    Disk brakes make some sense, i.e., separating the braking function from the rim function. Ideally, they can be merged with good rims and rim calipers. For those in adverse climates that abraid rims or where rim temperatures are a consideration (where I live, a four mile descent at high speed is normal) a disk can be a significant improvement. I have disks on my commuter bicycle, a Salsa cross bike, and they are excellent for both modulation and riding in crud. For racers on carbon rims, likewise, a light and reliable disk brake setup could be a significant improvement over the present clunky efforts to make rim brakes work on carbon rims.

  23. Jon2020

    I cannot wait for the bike companies to bring out disk brakes. It may be because I live in Auckland which is built on the sides of 50 different volcanoes and where the weather is either raining, just finished raining or just about to rain but going down steep hills in the wet when cars pull out in front of you and you can’t stop. That just freak the hell out of me.

  24. Souleur

    650b wheels…hell, i still haven’t even gotten a susser’ (as WV says it) front fork, nor rear (as i REFUSE), i can only afford one gear and the wheels are 26″. Would it be a value, to me, maybe, but so much of the bike is marketing and we fall for it, hook..line..sinker. We say we suffer, we ride to suffer, and then again we buy stuff to minimize our suffering and make our rides ‘quality’ and easier to some extent. When it comes to my mtn bike, i just expect to suffer and i know its gonna be by the boatload. And it sounds like i need to go to WV

    disc….I won’t be buying any anytime soon. I would if i lived in colorado and did alot of steep/long descents as that would definitely be of benefit, but I don’t and won’t anytime soon. I am new to cx, and it may well be good for that, but i will have to see

    the real revolution i see disc is for carbon clincher wheels too, since sooooooo many manufacturers are really me too makers and haven’t reliably cracked the nutshell on carbon clinchers in that of braking surface and the heat that can delaminate them. So, if i ran carbon clinchers (i am a tubie guy), i would, but don’t and so..won’t.

    debby downer..over and out

  25. Anthony F

    Spin out your crankset (53×11?), then sit on the top tube with your chest on the stem/ bar. One knee touching the fork and the other close to the front tire.

    I don’t think I’ll be able to go much, if any, faster. Too much wind resistance. Someplace steeper, maybe. But I’m probably maxed out there.

  26. Todd

    For cyclocross this year I switched from a canti cross frame to a 29er frame. I like the hydraulic discs but I’m not a fan of cable-actuated discs. So far, I’ve been frustrated with rubbing issues – even though I’ve never had that problem on my mtb’s. It may just be the cheaper hubs are out of spec and are warping the rotors. Also, quick wheel changes are not as easy which isn’t a problem if you have a back-up cross bike, but I don’t – this will also be an issue on road bikes. I do love the brake power, though. Modulation is excellent and wheel lock-up is not a problem with 160mm rotors. Once full hydraulic shift/brake levers are developed, I will probably switch back to a cross frame. I think the kinks can be worked out of the system. Do we need road dsics? No. Are they cool? Yes. And in my experience, most people like having cool stuff. Road biking remains a sport for the affluent and the consumers will buy the product once it comes out.

  27. tinytim

    I like to think in terms of faster. What makes one faster? Having a bike that is consistantly rideable and more than willing to accept hundreds of training miles per week is what makes one fast. Being able to repair one’s own gear is essential. A 3x cross wheel that is shod with a 25c tire is some serious shit. Buy some extra spokes and a key and you are set for 5 years. If you can afford 3 wheelsets then the prospect of having to wait 1 month for that specialty spoke from Italy that costs $100 won’t be an issue. But when you can only afford one wheelset, durability, function and availability come first. Road calipers have stopped riders for a hundred years. You want to descend faster, ride down hills more, alot more. Disc brakes, carbon clinchers and 800gm framesets are for vanity. Which is fine for some people. But ‘those’ people also need to be okay with being posers of the third degree. I’ve owned only one road bike for the last 4 years; a handed down Gunnar roadie, 105 throughout with 105 3x wheels. I’ve crashed the thing more times than I can count (once I even cold set the fork after a spill during a race and went back on to finish 4th). I used this bike to upgrade from cat6 to cat2 and still ride it to work. New tech stuff is nice, but you won’t see me buy it until its found in every store and has been proven by the test of time.

  28. J-man's Dad

    If I ever get another mountain bike, It will be a 29er. I’m over 6′, makes sense to me.

    Disc brakes will eventually be in the pro peloton. Better (Power+modulation) brakes ultimately means you can go faster. They’ll get smaller & lighter, maybe develop a new mounting standard from mtb discs, wheel/rim tech will improve & with Di2 & EPS its only a matter of time before the hydraulic disc drop-bar lever comes out, & ties it all together.

    I’ll never own one, but my Junior road & crit racing daughter, whos hand me down tires & wheels i use, just might.

  29. jorgensen

    I have ridden a 650b bike and I too think that for those under 6′ like myself it is the way to go. For my shorter spouse, no.
    On road bike disc brakes, I suggested an employee buy a disc brake flat bar road bike, he likes it, I test rode it. Discs are the future. The secret for me is Modulation.
    I would own a Volagi save two design choices, 130 mm rear wheel spacing which I am not sure will be the winner on a disc road bike as there are so many 135 mm wide hubs already around. and the tall head tube they made a part of the design for a given size. I would have liked 15 to 20 mm less. Even with a stem configured that projects parallel to the ground, it is just too high.
    Discs do seem to go through pads faster, but a small price to pay for better modulation.
    It will change how one descends though, you can brake later and go faster. I am not sure that I would want to ride in a aggressive rider mixed group if rim and disc brake bikes.

  30. Pat O'Brien

    I used to have 5 bikes before I retired. A commuter hybrid, a 26 full suspension mountain, a 26 hard tail mountain, a very nice carbon road, and a Trek 520 touring bike used to live here. Both mountain bikes had Avid BB mechanical discs. I think those are the best disc brake value for road and mountain. The simplicity, ease of home maintenance, and power of these brakes keep me coming back. Just keep the skewers tight. I retired and went to two bikes. A Trek 520 touring bike, and a Niner MCR. I am completely happy with these two bikes. But, a Salsa Vaya might end up taking the 520’s spot. And the Vaya will have Avid mechanical discs just like the Niner does. Touring bikes have heavy and strong wheels anyway, so discs make sense. And my MCR seems almost as smooth as my full suspension 26 did. So, large wheels and discs on the road have my vote.

  31. Les Borean

    Re: Roadie discs:
    I would love to ride in the rain but won’t because I don’t want to gouge the brake surface of an expensive wheelset.

    The other issue that concerns me is heat. Braking through the dicey descents in the Santa Monicas will heat the rims considerably. I was stopped at the bottom of Deer Creek last weekend, just past that radical hairpin, and I smelled something that brought me back to childhood in Rodeo, where my cousin had a tire recapping business. Hot rubber! Hot rims were roasting my tires and/or tubes. I immediately got riding again to provide forced-air cooling to the rims.

    Being the nerd that I am, I’ve stuck temperature-disclosing labels on my rims to determine the maximum temperature they attain in these descents, and I have recorded temperatures as high as 220F.

    On one occasion I got a blowout when the plastic rimtape softened during a descent, to the extent that the pressure from the tube forced dimples in the rimtape at the spoke holes. The tube ruptured at one of those points. A one-grand wheelset and the point of failure was the buck-fifty rimtape. I switched to old-fashioned canvas.
    Here’s the rimtape after the fact:

    Besides the increased possibility of blowouts I am concerned about the effect of the heat on traction. Heat affects the properties of all materials, and I’m wondering if the heat from braking changes the properties of tire rubber to the extent that traction is materially affected. This could contribute to accidents like Padraig’s recent crash at the bottom of the Tuna Canyon descent, where his rims were likely quite hot.

  32. randomactsofcycling

    I’m not one for the MTB question but as for Road discs, I would agree particularly with Champs in that the limiting factor is the grip of the skinny tyre.
    Other engineering issues aside such as beefed up forks, head tubes and spokes, will we see a return of 25-28mm tyres on race bikes, to help translate more powerful disc braking onto the bitumen?

  33. Chris

    Forget disc brakes. Put more R&D into alloys wheels. Call me a mid-twenties luddite but I just don’t gains with the disc brake that justifies them.

    If braking is so poor with carbon just ditch the carbon. Mavic’s Exalith coating increases braking power on an alloy rim and also looks just as cool as a carbon rim. The technology needs a bit of work but it is out there.

    Modulation. Road calipers have quite a bit of modulation. I don’t really even understand this argument. Disc brakes (hydraulic) I’ll agree have more but it is marginal. What are we modulating so much for anyway? Brake late and hard into the corners. Sprint out. Forget feathering the brake, sissies.

    Others have touched on the tires as well. No matter what speed I’m traveling at I can lock up my wheels with a road caliper. What more does one need?

    What I’m saying is road calipers already exist and are, actually, quite good at what they do. Alloy wheels already exist and with further advancements (if not already) can compete well with a carbon rim in a performance setting. Aerodynamics are a bit of an issue but look at Zipp. The 101 is a pretty quick wheel.

    I like cool new stuff just as much at the next guy but sometimes we (and the industry) need to step back and think that maybe it’s already being done right.

  34. slappy

    having just had a set of 27.5 lined up next to 26 and 29, they just aren’t different enough. and GarynFisher is great but the geometry of his bikes set 29rs back a good deal. Niner figured it out and their bikes are so freaking fast and fun and once you get it figured how to haul ass on big wheels, why go small? disc rubbing seems like an issue for to many people who are setting them up at home. ah well sadly avid hydraulic brakes are very common and suck so bad, that they call it elixiritus, best cure, shimano brakes. that being said, bb7s are swell, but even harder to set up perfectly, it can be done though, support your LBS. I’ve regularly steered people towards Niner hard tails instead of cross bikes, because they rip, and you get real braking power, plenty of room for fenders, blah blah blah. ah well, it’s snowing, time to get on the moonlander

  35. Alex TC

    29er, 650b, 26r: I’m into MTBking since ’85 and I’ve seen it all, come and go. After riding lots on both 26 and 29 I’ve decided that for a hardtail 29 wheels are the way to go, can’t beat. For a good, well designed and built full suspension it’s too much of a plush thing. Thus I chose a 26 ’11 Epic S-Works and passed the 29er. Snapier, lighter, flickier, just sweet. I’m open to the 650b for I believe it’s the best of both worlds but maybe in 3-5 yrs time.

    Disc brakes for roads: I consider myself pretty open minded to innovations but I see no point unless there are at least a couple REALLY GOOD, sensible improvements or performance advantages. Road brakes are just excellent as they are IMHO: they’re light, powerfull, elegant and K.I.S.S. to use, adjust, repair and maintain which is what cycling is a lot about for me.

  36. Pascii

    To change the subject (slightly), I have been pondering the idea of a 650B disc equipped road bike. If you get the geometry right you can run it with big tires for gravel road rides and then switch to 700C skinnies for Wednesday Night Worlds. The discs give you the flexibility. There isn’t a huge difference in outer diameter: 650B with 42mm tires provides about the same trail as 700C with 28mm tires. (28mm is as skinny as I run BTW)

    I am also lusting after a 650B MTB to replace my 13 yr old 26er. It seems like the perfect wheel size.

  37. AlMac

    MTB wheel sizes seems more like an opportunity to sell more bikes. Happy on my 26er. But, also happy for people to have a choice and ride what they like. No doubt I’ll get sucked into 650B or 29er one day. Of all my upgrades (dual suspension, carbon, wheels) tubeless wheels were the single greatest upgrade. Rolling at 20 psi is magic, especially with Stans.

    Road bike disc great for rain or when you need to brake a lot. Neither are problems for me.
    Wearing out your rims from braking isn’t a problem I’ve had, and that would be an excuse for new wheels.

  38. LD

    once upon a time there was the bottom of ones’ shoes, people scoffed, then there was drum brakes, people scoffed, then there was cantilever, people scoffed and now there is disc brakes….people still scoff. Its the nature of evolution. It might seem overkill on 14 lb road bike and we may see a rash of endos over the bars….. but thats not the brakes fault. It will be the norm and one day we’ll see something that we can’t even imagine with todays’ technology.

  39. Hobbanero

    I have ridden the Volagi Liscio with hydraulic brakes via a TRP Parabox, and I have Avid BB7 mechanical discs on my cross bike. The hydraulic discs on a road bike don’t feel more powerful, but they do have excellent modulation. I could easily keep the rear wheel just on the edge of its traction on a descent. It basically felt like I had 10 levels of braking, instead of around 4 on rim brakes.

    Of course, you also solve the carbon clincher overheating issue. But, now you have a rotor overheating issue, which is just as serious. I am sure the engineers will figure this one out. My mtb brakes survive 2300′ descents off Tam without losing any power or overheating. I wonder how different the load is. More speed on the road bike, but big tires with lots of traction on the mtb.

    The mechanical discs are a big step down from the hydraulics, and much closer to the performance of decent rim brakes in the dry, while keeping that performance in the wet as rim brakes get weaker.

  40. Les Borean

    Quoting LD: “…and one day we’ll see something that we can’t even imagine with todays’ technology.”

    If you look at a road bike from the ’50s it’s basically the same thing we ride now, less a bunch of refinements that have been invented over the years. And yes, now looking back we tend to regard them as “refinements”; but each change when it first appeared was regarded with suspicion as discs are now. I agree with LD.

    Further, I think a century from now the road bike and the sport that deems it will be basically the same as it is now — with a lot of refinements, with discs probably the most imminent.

    But what else? I see electronics and nano materials playing a part. There are now nano-based materials that have amazing qualities, and I think it’s reasonable to expect that these will bring us stronger, lighter frame materials in the future.

    ABS braking that will modulate front and rear brakes for optimal emergency stopping. Electronic automatic continuously-variable transmission. An air bag-like protection built into the helmet that will pop out and protect the face when the pavement is imminent. (That coulda saved me a couple of teeth in my past). These seem far-fetched now, but no more so than something like the derailleur seemed before it appeared.

    That’s what I think.

  41. rashadabd

    I am currently weighing the pros and cons of discs as I’m looking to get my first CX bike. All I can say is that the weight penalty is a serious issue right now and people have differing opinions about the real world benefits for most riders in most situations. Roadies tend to love lighter bikes, so I’m not sure how willing they will be to take on an extra pound to two for stopping power that they don’t really need.

  42. rashadabd

    One more point: the best CX racers in the world tend to be riding cantilever brakes right now and not disc, but that being said, discs are becoming more popular in the pro CX ranks and the world cx championships this year in Louisville, KY should be a very important test case to see which brake set up performs better in cross.

  43. Neil

    With disc brakes, the issues are weight and compatibility and sunk costs. Disc systems still weigh about a pound more than traditional brakes which in the road world is unacceptable. Bike frames are already crowded at the back dropout with the new 11 speeds and most frames are 130mm, not 135 which is the typical disc wheel hub. If you offset the wheel to accept both, you’ll get a tenuous wheel strength. Finally, you’ve got a lot of bikers out there with huge sunk costs in expensive non-disc wheels. It would cost around $800 to rebuild a wheelset with new hubs which is prohibitive for most people and not very attractive when you realize the extra weight and limited benefits in the switch – not too many average riders relish a ride in the rain. You’ll see it in cyclocross, but not serious roadies.

  44. Diablo de Acero

    I noticed that in the picture you show, the original (650b) is essentially a 26er with 650B wheels and brakes bosses.(check the pic for tire clearance on the front fork . Also toe clearance on the cranks, I have an older Ritchey that still I love. It would easily would convert with the help of Paul Motolite V brakes.

  45. Hunter

    I view 650b as a compromise. Most of the chicks winning and competing in World Cups are on 29’ers and are on average maybe 5’3″. I’m not a tall guy myself at 5’7″ and much prefer a 29er. Height is not an excuse.

    That said if you like it more, more power to you. If your not comfortable on big wheels just say so.

  46. Dan O

    I’ve been riding mountain bikes since ’84 and watched it progress into what it is today. I’ve been through most of the progression – no suspension, front suspension, full suspension – all XC based, super downhiller I’m not.

    Bike I’m riding now is the best set up for me: 29er hardtail. Most of the hype is true – rolls faster and easier to clean technical sections. Also more stable and corners better. The 29er rear wheel also seems to take the sting out, I rarely miss having full suspension.

    With that, having never ridden a 650B, would be curious to try one. If I had the dough to spend, would probably add a dual suspension, 5″ travel, 26″ wheel bike to the mix. Including pads and full face helmet, just to give the downhill/bike park thing a more aggressive go.

    Disk brakes on road bikes? Maybe. Cyclocross bike? For sure. Commuter/rain bike? For sure.

  47. Byron Go

    Just to clarify, the only hydraulic road disc brake bicycle on the market is the C59 Disc. It’s a beautiful exclusive set of Formula brakes, but who knows how the hell to service them.

    But if you can afford this bike, then you can pay to find someone who can fix it 🙂

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