I ride MTB in a coastal town where all roads are dirt roads with lots of uphill/downhill. Nothing extreme, I just ride to relax and enjoy the landscape. I have mechanical disc brakes and after a 2-4 hours ride session my hands hurt (too much braking). I have never ridden with hydraulic brakes, but it seems to me that they will be easy on my hands. Should I change to hydraulics?
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The difference between mechanical and hydraulic disc brakes (or v-brakes and cantis, for that matter) shouldn't equate to more or less usage. Either your disc brakes need to be serviced, or your issue is more a result of bar setup and body posture. Could you describe a bit about the brakes (age, brand, whether they've been serviced...) and a bit about your setup (i.e. resting lots of weight on your hands and wrists).– WTHarperOct 26, 2012 at 17:05
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Brakes are Shimano Alivio. Age 3 or 4 years (bought second hand). I have made near 2.000 kms. Never changed pads; they look good to me. They work well; just need lot of pressure for complete stop while running downhill (~30-50 k/h). I changed the cable casing for a new one (teflon inside). My handlebar is narrow (shoulders wide) and my setup oriented to minimize weight on my hands and get an upright position (I weight 100 kgs). As I said, I enjoy looking the landscape. I do basic maintenance myself, but take it regulary to my mechanics.– user5369Oct 26, 2012 at 17:30
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2Brake lever pressure vs stopping force is a function of mechanical advantage and pad/disk composition. You can get the equivalent mechanical advantage with hydraulics, cables, or even rods and levers. Hydraulics have the advantage that there's a hair less friction in the mechanism, and generally less "slop", which would allow for brakes to be set up with less "pre-travel" before they engage. But this advantage is largely negated with proper maintenance.– Daniel R HicksOct 26, 2012 at 18:05
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1You say your hands hurt from too much braking, but braking fatigue ("arm pump") hurts your forearms, not hands. Painful hands tend to result from poor gloves, grips, posture, etc.– cmannett85Oct 27, 2012 at 7:05
4 Answers
I have or have had bikes with mechanical rim brakes, mechanical disks (shimano deore), hydraulic discs (also shimano deore) and recently hydraulic rim brakes (Magura hs33).
The experience I had says that:
- The force you have to apply depends on brake-system preload / elastic constant (lever spring + actuator spring), cable friction, and actual, braking, pad friction.
- Pad friction means how much decelerating power you'll get for a certain force applied by the pad against the braking surface. Good quality pads brake more with less force. Bad quality, or dirty, or whatever-else-not-ideal pads require more force to get the proper braking power.
- Cable friction means, the more cable friction, the more force will be irreversibly lost between the lever and the actuator. At extreme cases, with very dirty/rusty cables, you get enough friction that you get an absolute maximum beyond which no additional force on the lever creates aditional force at the braking surface. THIS IS THE MAIN PLACE WHERE HYDRAULICS MAKE A DIFFERENCE: they always have a very low (inexistent?) cable friction, and that doesn't change even after miles and months in the muddy rain, for example.
- At last, system preloads mean the force you have to apply to the system BEFORE it even starts to break. For example, my Magura HS-33 has too much preloat at the lever, and if you ride lightly, only correcting speed now and then with the brakes, even so the hand gets tired, because even for a slight touch you have to overcome half the lever course of a relatively stiff spring preload, whereas on modern, race-oriented disc systems the lever action is so light that it seems like there is no actual brake connected to the lever (at least until the pads hit the disc, of course).
So, I'd say the hydraulic systems are well worth the upgrade, but unless some facts are taken into consideration, sometimes the magic might not happen, specially if the braking pads are not doing their job. Also, a v-brake with new and well tuned cables/cable-routers, killer pads and decent levers can beat most fancy disc brakes around.
Hope this helps!
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2"Also, a v-brake with new and well tuned cables/cable-routers, killer pads and decent levers can beat most fancy disc brakes around." - Until it rains. Oct 27, 2012 at 7:01
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1@cmannett85 Yeah, that's why I wrote "can beat" instead of "will beat" or "will ALWAYS beat"... I see a case for rim vs disc brakes, but the world would be a much happier place if hydraulic actuators (instead of wire cables) were the default for bike brake systems... Oct 27, 2012 at 13:53
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"HYDRAULICS MAKE A DIFFERENCE: they always have a very low (inexistent?) cable friction"... Close but no cigar. When you apply pressure at the lever, a certain volume of fluid need to move before pad contact occurs. The flow will be proportional to the pressure and the hydrodynamic resistance calculated from the radius and length of the channel (hose). Hydrodynamic capacitance also exists when fluids are compressible and/or the channel has elasticity. en.wikibooks.org/wiki/Microfluidics/…– EmyrNov 16, 2015 at 10:46
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@Emyr Yeah, you are right, I guess I meant static friction... Anyway, compared to a sub-optimal cable, the friction is much lower. Nov 16, 2015 at 11:20
I'd recommend giving your current brake installation a good service before considering spending money on an expensive upgrade.
Hydros are great (I have them on my bike and enjoy riding with them), but a well-maintained braking system should be more than adequate in all reasonable riding conditions. Hydros would have advantages if you're into mountain riding as a sport, but for day-to-day use you probably won't notice much difference.
You say you've never changed your pads because they work. A pad can last a good while to be sure, but they do tend to become gradually less effective as they wear (more force for the same braking needed). You might want to look into changing the pads for fresh, good quality ones. That should give an noticeable increase in breaking power.
Similarly, the discs or rims that the pads press against can wear, though that's very unlikely to be a factor unless the brakes in question are very old. What is more likely to have an impact is dirt and other contaminates on the braking surface. Mud and dirt, lubricating oil from your bike, the remains of old brake pad material and what have you can build up on the surface. If you clean the surface thoroughly then you should notice further improvements in the stopping power of your brakes.
The cable in mechanical systems can stretch, fray, rust and so on. As it's a mechanical moving part it also needs to be properly lubricated. As the cable stretches with use you should adjust the brakes to counter. You should also apply some kind of lubricating grease or wax to the exposed portions of the metal cable with the brake in both the released and applied state. Finally, if there's any sign of rust or fraying in the cable, get it replaced immediately!
All this maintenance should make a very noticeable improvement in the stopping power of your brakes. More effective braking means less effort needs to be used when braking, and hopefully less strain being put through your hands.
You may also want to invest in a good pair of padded cycling gloves, they also offer a measure of protection from strain on your hands.
If none of the above helps enough then that's the point where you might want to start seriously looking at replacing your brakes. However, doing the above is likely to be effective in reducing the amount of effort you need to apply when braking, and it's a lot less expensive then replacing the brakes on your current bike.
In order to brake you apply force on the brake lever that is then transferred to the braking surface (e.g. disc and pads). The advantage of hydraulics is the efficiency in which force is transferred (i.e. reduced system flex). Cable actuated disc brakes will have more compression in the cable housing, resulting in reduced efficiency and potentially tired hands from the extra force applied during extended braking.
That said, you can greatly improve cable disc brake efficiency by upgrading the cable housing to "compression less" housing (e.g. Avid Flak Jacket). This could be a much more cost effective option than switching to hydraulics. I did this on my commute bike and the performance was quite close to hydraulics, but did take some time to properly set up.
I had some Shimano XT hydraulics on a mountain bike, and now have Avid BB7 mechanical disks on my touring bike. I don't know whether to attribute it to the lack of cable compression or some other mechanical advantage, but there's no question that the hydraulics feel much easier and controllable. It is also a more linear feel (or "better modulation" is a phrase I sometimes hear used) -- you get more braking right at the beginning of the lever pull because you don't have to first squish out all the flex in the cable and cable housing.
By contrast, my mechanical disc brakes, while very strong, have a bit of squish at the beginning, and don't subjectively feel as nice. I still choose not to run hydraulics because of the increased vulnerability (hydraulic line punctures) and difficulty of doing field repairs (particularly inappropriate for a touring bike). But the hydraulics, subjectively, definitely feel much stiffer and stronger. Since you're a bigger guy at 100 kilos, and braking quality sounds important to you, I don't think you'd be crazy to want to try switching over to hydraulics to see if they make a significant difference.