Disc vs. Rim Brakes

With technology progressing faster and faster within road cycling, it’s no surprise seeing hydraulic disc brakes not only making an appearance with the industry but is it taking over? We are going to look at the performance of hydraulic disc brakes, the benefits, the downsides, and how the outdoor elements will make disc brakes helpful or not. 

 At this point in the game, many cyclists are aware of the performance of rim brakes on carbon braking surfaces when descending at high speeds, and getting caught in unwanted weather conditions. The answer may be similar across the board, “That made me a bit nervous” was my reaction at least when descending at 78 km/hr on a sunny and dry club ride one Sunday morning. I can only imagine what may have been the outcome if it was wet outside. On a separate occasion, descending the same route on Shimano Ultegra hydraulic disc brakes was a different story. Not only did the hydraulic disc brake allow more stopping and speed control on the decent, but also they felt much more confident from top to bottom. The workings of two are very different, with the disc set up, as soon as the rider applies minimal pressure to the brake levers, the bike will start to slow down, as the pressure is continuously applied, the control increases without the feel of the rear of the bike sliding of the out on control. In wet or mild snowy weather conditions, it’s a no brainer that the hydraulic disc system outperforms the rim brake when stopping or even controlling the speed. 

The big question, which is faster on the road? Rim or Disc? The hydraulic disc set up does have a bit more weight, and not as aero as a rim brake but, we have to look at the type of riding that’s being done. On a steep descent, the rider will have more control of speed and braking, allowing for a more controlled environment, rim brakes tend to lock up and slid on a steep descent. To answer the question, is disc faster? We would like to say they could allow the rider to be more efficient. With controlled braking and speed, more confidence will be within the rider as they are descending around corners or even down a hill that may be wet, therefore getting down the hill in less time. 

The weight of the of the disc set up is slightly heavier, on average the disc set being about 150-200 grams heavier added to the total weight of the bike. Along with the heavier weight, the bike will take an aero penalty, but not by much. The average rider can find ways to shed 150-200 grams of weight off on other areas of the bike, and the aero penalty not much to write home about. Comparing the levers, bleed hose, mineral oil and disc calipers to the traditional lever, cable/housing, and rim caliper, the weight is not too far off from one another, or at least it’s small enough to find other areas to lose the additional weight off the bike or even the rider. 

 How much will the disc set up cost? Along with a bit of extra weight, will come with a bit of an extra cost. On average, the price difference from disc to rim can be about $400-$500 more for the disc. Does the price increase justify the braking power? We think yes, a one-time investment to increase the overall braking power and speed control of the bike is well worth it, especially when caught in wet conditions or speeding down a steep hill. 

 Does the disc set up come with any additional maintenance? Yes, but quite minimal. When setting up from new, the brakes feel well, just like a cable rim brake, solid, confident and the ability to easily adjust the reach of the brake levers. The hydraulic disc set up should always have an annual check-up to ensure pads have not worn down, the bleed hose has no bends or imperfections’, and most importantly air has not found its way into the system. We strongly recommend taking the hydraulic braking system to a pro cycling shop where an experienced technician, tools and knowledge are available. What riders are able to do is try to avoid touching the disc with bare hands, natural oil can find ways to the pads and contaminate them, once pads have been contaminated, they make a loud “squeak” noise when braking, no one wants to hear that on the club ride. Bleeding on an annual basis isn’t always necessary, but will allow the braking performance to feel like new at the start of every season, and gives the rider confidence on each and every ride. A downside to disc is many riders aren’t familiar with the simple maintenance that may be required on the side of the road, and no one wants to tamper with brakes, especially if they don’t know the way around these parts. Luckily, Shimano or Sram and engineered the braking system to work and work very well that these occasions occur less often to none. If the desired tools and instructions can be obtained by cyclists who would like to educate themselves on the subject. 

In conclusion, rim vs disc is still a personal choice, but many riders who try the disc set up are more impressed than expected. Overall the hydraulic disc set will add a bit of extra weight, may take an aero penalty, but still can make a rider more efficient depending on circumstances, add a bit of extra cost to the initial set up. If the cyclist is a more than the casual rider, a couple of days a week and a long ride on Sunday morning before lunch, the hydraulic disc system is certainly worth the minimal trade-off to get the most control out of their riding experience. Is the Hydraulic disc breaking system here to stay?

 We think so. Ride strong and be safe. -James

1 comment

  • Keith: March 01, 2019

    Good article will these be on sale at the Toronto show as I will want

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