Mechanical vs Hydraulic Disc Brakes

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carlosfandangus

Über Member
I took my Avids off and replaced with Shimano, I kept the set with a view to selling them on, they still looked good, however I eventually threw them in the bin, I would only have been selling a problem, cable discs, never entered my head to try them
 

figbat

Slippery scientist
Shimano brakes use non-hygroscopic mineral oil and are rather better designed.
This is true, but there is a downside. If any water does get into the system then it stays as free water and works its way to the lowest point, usually the caliper, where it sits waiting to boil and/or corrode the alloys there.
 
I've recently replaced my commuter bike and gone from cables (BB7) to hydraulic discs (Shimano). Whilst I was happy with the BB7, I don't think I'd go back.

If / when I replace my road bike(s) I can see me making the move from rim brakes to hydraulic discs there too.
 

rogerzilla

Legendary Member
Cars and motorbikes have provision for fluid expansion. Some bike systems also do (I had a Hope Mono setup once, which used bellows in the master cylinder). The trouble with DOT fluid in bikes is that you want the system sealed against the outside world and you also need to minimise weight. Both of these conspire against a simple reservoir as used on motor vehicles.
 

mythste

Veteran
Location
Manchester
Lost a front brake during a lairy mtb ride due to a damaged/burst hose. Still had a back brake so carried on regardless and the other riders caught me up eventually..... :whistle:

If you do have problems with hydraulic brakes it is rarely so catastrophic, and even then you still bave the other brake as they are separate systems. Don't be afraid of hydraulic brakes!

Respectfully, if anyone uses you or the gear you use as an informant to what they should do on a bicycle, they will die. :laugh:

Get hydros for MTB, cable for road, IMO.
 

Vantage

Carbon fibre... LMAO!!!
The thread title is Mechanical V Hydraulic Disc Brakes.

Noooooo! Really? Who knew :rolleyes:

they take less effort at the levers than mechanical for the same braking results

What I said to the op, whom I presume is thinking about going to discs from rim brakes is that mechanical discs require no more pull at the lever than rim brakes and so he'll not notice the extra pull they require over hydraulics.
 
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Eziemnaik

Über Member
Indeed, I've said in another thread today that I haven't looked near a Rival hydro setup in nearly 5 years.. Same pads and same DOT4 fluid, which I should probably change**:laugh:

**yet that would be fixing something that isn't broken
20200521_212655.jpg

My rival brakes also were completely problem free and low maintenance (change the pads, wipe the pistons)...untill they weren't
Rear brake failure was not deadly but could have been
A few different opinions from different mechanics about what went wrong, common response was I should have bled regularly

(Also I was positively surprised by the modulation and power on my GF triban rc 500, some dirt cheap promax brakes, certainly close to rival I have, or 105 hrd I tried, YMMV)
15917077183284110422123548523007.jpg
 
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OP
OP
MntnMan62

MntnMan62

Über Member
Location
Northern NJ
Thanks to everyone. Good info here. I'm going to do some more reading up and will see what is available with the bikes I'm thinking of getting.
 

Moodyman

Legendary Member
The only downside with hydraulics is if you frequently carry the bike horizontal or upside down i.e. in the boot of the car. You risk getting air into the system and losing braking.

If you choose hydraulics, better off with Shimano as they use mineral oil and it doesn't degrade with time like Dot fluid does. Replacement pads are usually cheaper and more widely available.
 

Jody

Stubborn git
The only downside with hydraulics is if you frequently carry the bike horizontal or upside down i.e. in the boot of the car. You risk getting air into the system and losing braking.

Couple of pumps on the lever when the bike is the upright would sort that out. Any air in the reservoir might migrate but it's not really an issue.
 

fossyant

Ride It Like You Stole It!
Location
South Manchester
The only downside with hydraulics is if you frequently carry the bike horizontal or upside down i.e. in the boot of the car. You risk getting air into the system and losing braking.

If you choose hydraulics, better off with Shimano as they use mineral oil and it doesn't degrade with time like Dot fluid does. Replacement pads are usually cheaper and more widely available.

Nope, doesn't affect my bikes being tipped up.

Got both oil and DOT in two bikes - both absolutely fine (just means I need two bleed kits and fluids). I actually prefer the SRAM bleed solution as the bleed ports are less messy, but that's all.

There are plenty of folk who don't like Shimano, and a similar number who don't like SRAM. Horses for courses.

You rarely get a catastrophic failure with hydraulic - it will start to go spongy. As Skol says, he got a damaged brake hose (rare) from a rocky MTB ride, but he could tell his brakes were failing, rather than bang, cable gone.
 

Tom B

Guru
Location
Lancashire
Agreed. Nothing to fear with hydraulic, can be easier to set up than some cables and usually require less adjustment.

I've used and still use.

Shimano M615 and M6000
Avid/SRAM Level 1
Tektro. Auriga and something I've forgotten

And rate them in that order. The Shimano are my favourite for use and maintenance. I binned one set of tektro that felt horrible.

The only issue I have had is a cracked tank due to a crash and a goosed caliper (Shimano) that meant a replacement and that was after many years of use including lots of salty manky commuting.

If I was going to buy some tomorrow it's be Shimano.
 
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