from Rookie’s keyboard
Hello, friends
Let’s get this Friday post started.
Today, I will share a profound revelation with you (slight sarcasm here).
I prefer mechanical disc brakes over V-brakes any day of the week.
Why?
- Reliable braking performance, even in less-than-ideal situations
The ultimate advantage of disc brakes (all types) is their consistent stopping power even in wet and dirty conditions.
The brake rotor is small compared to the rim and positioned away from the tire and the ground. Thanks to its protected position, it isn’t affected as much by water and dirt.
The rotor provides a larger contact area for the pads than the brake track of a rim.
That doesn’t mean that braking doesn’t suffer in wet conditions, but the downgrade is much smaller, especially when using disc brakes of higher quality.
If the bike in question is going to be used off-road and in all weather, disc brakes are a logical choice.
Stay away from no-name entry-level disc brakes because they tend to perform poorly even though the fundamental technology is superior to that of rim brakes.
- The wheels don’t have to be true
A disc brake will continue to operate even when the rim is out of the true as long as the rotor is straight.
Since the rotor isn’t subjected to impact during riding (unless there’s a fall), it’s a lot less likely to bend it.
And even if does get bent/warped, it’s somewhat faster and easier to get it back to its proper shape with a tool like the one below. You could also use an adjustable spanner wrench.
And, of course, you could also make your own tool with a piece of steel, an angle grinder and a metal file (to soften the rought edges).
- The rim doesn’t have to be replaced
Disc brakes do not wear down the rim. Only the rotor and the brake pads need replacement.
You can use the same rim as long as it’s intact, which provides a greater incentive to invest in a set of high-end rims.
Of course, nothing is perfect. Mech. disc brakes have their cons:
- Weight
The rotor and the caliper add weight. If the goal is to build the lightest possible bicycle with brakes…..discs aren’t a good choice.
For recreational purposes – the weight savings are irrelevant.
- Expensive
Disc brakes are more complex and cost more. But mechanical models are on the cheaper side and a quality set can be acquired for a reasonable sum.
I’ve used entry-level Shimano mechanical disc brakes for years. They are perfect for my needs.
- Rear Racks Hate Disc Brakes
Very often the caliper will prevent the installation of a standard rear rack. Whether this will happen depends on the frame’s architecture.
When I was using a rear rack on my hardtail, I had to purchase a special one with L-shaped support legs.
And now, let’s talk about the positives of V-brakes – let’s face it – there are many of those:
- Cheap
Vs are older and simpler technology. You can buy high-end models for a lot less than it costs to acquire a set of disc brakes from the same class.
- Strong Stopping Power In Dry Conditions
Properly adjusted V-brakes offers a lot of stopping power in dry conditions. The level of effectiveness is comparable to that of disc brakes.
- Simple
Vs are not complicated. When you press the lever, a cable squeezes the two brake arms together. The arms pivot around the brake bosses and the brake pads grab the rim.
Unlike disc brakes, V-brakes do not require a brake rotor and have visible brake shoes making calibration easier.
Most of the adjustments are done with an Allen key.
- Universal Replacement Parts
V-brakes follow the same mechanism across brands and allow you to easily find replacement parts and brake shoes even when traveling to remote destinations.
- No Interference With Front or Rear Racks
V-brakes do not create rear/fron rack issue because the body of the brake is far away from the support legs.
- Lighter
The table below compares the weight of V-brakes and mechanical disc brakes.
V-brakes | Weight | Mech. Disc Brakes | Weight |
Shimano Deore XT BL-T780-B | 196.6g | SRAM BB7 | 170g |
Shimano Deore XT BL-T780-B | 174g | Avid BB5 | 215g |
Shimano Deore BR-T610 | 168g | TRP Spyre SLC | 146g (road) |
Shimano Alivio BR-T4000 | 188g | Hayes CX5 | 195g (road) |
Tektro M530 | 158g | Shimano BR-R317 | 183g |
Tektro M730 | 158g | Shimano BR-RS305 | 170g |
The weight difference between V-brakes and mechanical disc brakes is small.
However, the mechanical disc brake column shows only the weight of the caliper without the caliper. The rotor itself easily adds 100 grams to the whole set-up.
In some cases, a V-brake can save close to 200 grams per wheel or 400 grams in total. In the world of cycling, this is considered a lot.
For me, those advantages don’t matter all that much and aren’t enough to outweigh the cons below:
- Lower Braking Power In Wet Conditions
The rim has a large surface that’s very close to the ground and in contact with the tire. As a result, the rim gets wet and dirty (lol).
When the brake shoes grab the rim, the first few spins of the wheel clean the wheel and only then full braking power is reached.
For that reason, V-brakes are considered sub-optimal for riding in the rain and off-road.
- The Wheel Must Be True
The pads of V-brakes have to be close to the rim for the rider to quickly initiate braking. If the rim is not true (round) and has deviations to the right or left, one brake shoe will touch the rim before the other. The contact will happen at the deformed location.
- The Rim is a Consumable
Sooner or later, the brake shoes will wear down the brake track of the rim. When that happens the rim should be immediately replaced. If it’s not, the wheel may collapse unexpectedly.
- Limiting Tire Clearance & Mud Accumulation
V-brakes encompass the wheel and thus limit the size of the tire. Usually, this isn’t a major problem because there’s plenty of space to install a wide wheel.
Another shortcoming is the possibility of mud accumulation around the brake. In extreme cases, the clogged area may even prevent the wheel from spinning.
- Heavier Non-Aero Rims
V-brakes require rims with a brake track. The brake track is a thick, flat part of the rim that the brake shoes grab and rub against. The brake track adds weight to the rim and reduces its aerodynamic properties by a slight margin.
Until next time,
Rookie
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