Cross Bikes and Disc Brakes. Welcome To The Jungle

By now, most of us have seen the countless online and print articles about the next big thing in cyclocross and (gasp!) road bikes being disc brakes. Of course, there is a ton of info about all the positives and negatives associated that come with using disc brakes and skinny 700c wheels and tires and some of the information ou there is actually true.  A lot of the buzz being generated is also the bike industries way of creating “the next big thing” and pushing more people to buy a new bike. None of this really helps you, Joe (or Josephine) Consumer if you are trying to wade through all the ad copy and technical mumbo jumbo and just want to buy a new bike and not be that person stuck with outdated technology. So what should you do if you are considering a new cross bike and the added wrinkle of disc brakes or no disc brakes leaves you with a little paralysis through analysis?  Here’s a few things that you might want to keep in mind as you consider looking at a cross bike equipped with disc brakes.

1. Disc brakes are heavier. They require heavier hubs, disc rotors, reinforced frames to mount the discs to, and the brakes themselves are heavier. Yes, as discs become more common place, the weights will come down, but they won’t ever be as light as a rim brake. Especially at the low and mid-range models.

2. Disc brakes are right now only really available in a mechanical version. There’s a couple of options for a kludge of a cable actuated hydraulic brake system, but they are expensive and not an easy retrofit. Everything out there is a mechanical system that is heavier, uses one pad to flex the rotor into the other pad, and requires you to constantly adjust the brake at the caliper to compensate for pad wear. You can’t just turn a barrel adjuster at the lever and have the brakes keep functioning as effectively. While that will pull more cable and move the pads closer to the rotor, it also changes the actuation of the internal cam in the caliper and makes the brakes weaker and weaker each time you do it. Hydraulics are self adjusting for pad wear. It’s why you’re always surprised when you take the car in for new tires and they tell you your brakes are shot. They felt fine on the drive. The pedal always goes to the same place on the floor. That’s because hydraulics self adjust for pad wear and will work the same until the brakes are completely worn out.

3. All those wheels you use on both your cross bike and road bike? They are now only good for the road bike. No more grabbing the road bike’s wheels to use as an emergency back up. You can’t offset the cost of deep section carbon wheels by telling your significant other that they will be for crits and cross racing. If you fancy yourself as a “real” cross racer, you are going to be investing in quite a few new sets of wheels that will only work on one bike. “But can’t I just share wheels with my 29er and my cross bike, then”? Probably not, especially in the near future. Almost all mountain bikes are going to be equipped with thru-axles front and rear within the next couple of years, meaning your cross disc wheels with QRs are going to be quaint hoops only good for one bike.

4. Discs are here to stay and will become the standard eventually. But what version will be the standard. When mountain bikes first were getting discs, there were multiple standards for how the rotors attached (3 bolts, 4 bolts. 6 bolts, splines) and how the caliper attached to the frame or fork (IS, Post Mount, Hayes 22mm, Rock Shox, Sachs). Right now, road and cross bikes use a 130mm spacing for the rear wheel. Most of the industry agree that it will bump up to 135mm for cross bikes to fit the disc, but there are a few models out there with a 130mm disc hub. Those hubs are almost impossible to locate should you need to replace a wheel. years from now?

“Wow! That seems like a lot of doom and gloom towards disc brakes. I should stay away from them”. Not so fast. Disc brakes also have a ton of advantages. Here’s a few.

1. Discs work better. Everywhere. All the time. Sure they are stronger and are inherently better in the wet, but what really makes their performance shine is that they work the same regardless of conditions. That consistency allows you to not have to factor anything in to how you apply the brakes. you never have to clear water from a rim. Your rim can be covered in muck. It can be a bit out of true. It doesn’t matter.

2. Do you like to take long gravel rides in all sorts of conditions when you aren’t racing? Do those rides have long descents? Discs are the way to go. Break a spoke out in the boonies? No problem. As long as the wheel still turns through the frame, you can ride it out and have perfectly functioning stoppers.

3. Have you ever looked at the difference in materials between a rim brake pad and a disc brake pads? One is squishy rubber and the other is some sort of really hard metallic looking stuff. Guess which one lasts longer? Sure, you’re gonna have to still by new brake pads every now and again, but way less frequently than you did with rim brakes.

Where does that leave you? Options still as clear as mud, right? OK, lemme break it down a bit more.

If you are a racer, don’t worry about your new frame or bike not having discs. You will save some money as rim brakes are cheaper, so you can funnel that money back into entry fees and paying me to huff tubular glue while I mount up your tires. You can use all of your other road and cross wheels. Set a set up with clinchers to train on. Rob your wife’s road bike for a set of pit wheels. Be brave an use those deep section carbon hoops. They are faster and make really cool noises when you get them spun up. Also, you are a racer, so the odds of this bike being a lifetime frame are pretty small. You’re either gonna crash it and dent the top tube, or you’re gonna cover that dent with a sticker and sell it off to finance the newest toy in a couple of seasons. If you get a bike with discs, no problems either, just be okay with having less wheels at your disposal. Pick a good tubular and keep a spare around in case you slice it.

Not a racer, or just the occasional racer? Do you only have one set of wheels for everything? Then if the bike you are looking at has discs and the rest of the components looks good, go for it. Find a good deal on a used cross bike, but it doesn’t have discs? No biggie. Slap some mini-V brakes on there. They are worlds better at actually stopping you than a traditional cantilever and for the money, might be the bestest, cheapest, goodest upgrade you can do.

Gonna buy a cross bike for everything a cross bike does well except racing cross? Light touring? Adventure riding? Gravel grinding? Commuting? If it’s a new bike. go for the discs. If it’s a used bike and it doesn’t have them, see the paragraph above and don’t sweat it.

Basically, the longer you actually plan on keeping a bike (not the fake amount of time we always tell our spouses. “It’s gonna be the last bike I’ll ever need. I swear”.) the more you should look into getting a bike with discs. If you have a stable of wheels with tires for every condition, then you will gain more by having those treads at your disposal than you would with the better breaking. If you get a new cross bike every couple of years, don’t worry about having discs. If you have a cross bike now but you hate the braking with the old fashioned cantilevers so that’s why you are looking to get a new bike with discs, then throw down $40 on a set of mini-v’s and see if that helps. Besides, if you decide that you still want discs, then you aren’t out much coin and your old bike is now way easier to sell.

Quick Disclaimer. I sell Kona bikes and they have been making cross bikes for eons and they do it well. There are options for discs and non-discs from them. This year, the top end models are non-disc, and the other versions are disc. Next year I would expect to see more disc options. I would also expect to see at least one model that is non-disc at the high end as well. So while I sell a brand of bike that makes me biased, I’m pretty certain I’d give you the same following speil regardless of whatever brand you were inquiring about. I always try and sell a bike to a customer that will fit their needs instead of getting a customer on something just because I have access to it. A non sale because I can’t get what you need is much better for me than trying to force you onto a bike that isn’t what you want or need.