Mountain Biking - Mech disc brakes vs hyrdo

Hi
What is the difference between mech. disc brakes and hydro disc brakes? and what are the pros and cons of each?

pacu1

mech work by wire, kinda like your regular rim brakes except with a rotor and caliper
hydro work more along the lines of a car brake, with fluid and pistons instead of the wire

cable:

pro: easy ot get a replacement cable, quick to setup, light weight.

cons: not as good of performance as fluid, cable stretch


fluid:

pro: best and most consistant stopping power, has no significant issues that are comparable to cable stretch.

cons: uses special tube instead of a cable housing so if it breaks in the middle of whereami, you might have a hard time finding a replacement part. Also takes more time to set-up, since you have to bleed the lines, etc. Also for field service fluid has to be handy. Not all disc use the same fuild, so carrying some is highly reccomended since the bike shop in that area might not carry the fluid you use.

I've been very tempted to go fluid, however I'll stick to my mechanicals. Just knowing all i need is a regular brake cable is a very comforting thought.

You forgot to mention the Pros and Cons associated with costs.

Mechanicals are cheaper, especially when upgrading. Why? Usually you can use the same brake lever as your vee (linear pull) brakes.

Also, Pro for Hydros is Modulation. The "feel" at the lever. Instead of a on or off feel, you can have a "barely on yet not enough to really slow me down stay in control for that next big turn" feel at the lever.

True, the feel of my mechs are not that great around turns, but i do have the modulation down...you just dont get that nice personal feedback that you get with a firmer brake system, most of it is just knowing how far on the lever to go, since the feedback is kind of sloppy on my set.

My set are deore mechanicals with LX levers. I'm seriously thinking of going to another brand, maybe Avid.

i find the pro that relates to "easy to fix in the middle of whereami" is not really much of a pro for mechs. unless you carry spare cable and a wire cutter - but my wire cutter is way too huge to bring along on rides.

not that i'm dissing mechs or anything :p

unless you carry spare cable and a wire cutter

Like I do? :D A lot can be said for having pre cut cables on hand

Be core, ride without brakes. They are overrated at times anyways :D

Avid Mechanical discs, with Avid levers that have the Speed Dial feature, (go check on the Avid part of the www.sram.com site) and full housing runs over good stainless cables feel sooooooo buttery. Excellent modulation, plenty of power. 185mm up front, 160mm rear rotor.

It's an easy/no brainer setup to install and maintain. And yep, I carry a spare brake cable, precut in my toolbag part of my pack. I've not had to use it yet, though I've been on several rides where people have developed problems with their hydros........

Catatonic, if you want to get better performance for minimal $$$, hop on E-bay and pick up some Avids. You can normally find a full set of calipers and lever going for $100 or less.

They will feel WORLDS above the Sh#tmano Deore/LX combo you have. Really.

i always ride with a leatherman...while not a perfect wire cutter, it will do for a field repair...plus it does so much more that it's like having nearly an entire toolbox in your seat bag.

I also have a multitool that is a socket wrench/ closed end wrench/screwdriver set/hammer but it's too big to carry.

i always ride with a leatherman...while not a perfect wire cutter, it will do for a field repair...plus it does so much more that it's like having nearly an entire toolbox in your seat bag.

I also have a multitool that is a socket wrench/ closed end wrench/screwdriver set/hammer but it's too big to carry.
I normally walk around with a Leatherman and / or a Swiss Army Knife, I always find a need for having them.

hmm, can you use the avids with the LX levers? Only reason I ask is they are those blasted integrated shifter types...so if I have to replace the levers it's going to get costly.

hmm, can you use the avids with the LX levers? Only reason I ask is they are those blasted integrated shifter types...so if I have to replace the levers it's going to get costly.

yep, you can. even just using the avid calipers instead of the deores will make a huge improvement.

i'd not reccomend buying any other mechanical than Avid.

I've ridden on both mech and hydro brakes and I can vouch for the stopping power it's alot stronger on the hydros and it's so much smoother. That is just my opinion and that is comparing the avid mech bb7 to hayes nines

I have never had issues with stopping power using Avic BB7. I hear some people complain how their hand gets tired with them, i wont comment on that. But i dont see myself going to hydro i think its more than most people need anyways.

i'm 400lbs, I find the hydros w/ 6" rotors to be inadequate sometimes

i'm 400lbs, I find the hydros w/ 6" rotors to be inadequate sometimes

Well, you weight more than most high performance motorcycles do, maybe you should try some 12" motorcycle rotors. Or lose 200lbs.

Well, you weight more than most high performance motorcycles do, maybe you should try some 12" motorcycle rotors. Or lose 200lbs.

Hmm lose 200 pounds, that´s kind of rude eh? :rolleyes: But it´s comforting to know that there are brakes that can take that sort of abuse :)

doh - precut cables didnt think of that. tell me you guys dont carry precut derailleur cables too?

doh - precut cables didnt think of that. tell me you guys dont carry precut derailleur cables too?


yep. only the cable, no housing. one brake and one shift cable, long length, with the end cut. a spare chainring bolt, crank bolt, a couple rotor bolts, some standard size m5 and m6 bolts, spare disc pads, sip ties, duct tape.

and at one time or another, i've ended up using it all. either on my bike, or someone elses.

I just carry an uncut cable...cut it when i need it...that way it can be used on any part that fubars. If the rear cable fubars, I might keep it to use for front brakes or front deraileur, etc.

yep. only the cable, no housing. one brake and one shift cable, long length, with the end cut. a spare chainring bolt, crank bolt, a couple rotor bolts, some standard size m5 and m6 bolts, spare disc pads, sip ties, duct tape.

Sounds like somebody rides WAY out in the middle of nowhere!

I bet you don't leave the house without a whole pack of condoms in your pocket either... :D

Back to the brake subject...

Anyone use the Avid BB7's with their Full Metal Jacket Cables or Flak Jacket Cables and can compare them to Hydro's? Or compare to standard cables?

I bought Flak Jackets but I'm thinking of reselling them and getting the Full Metal Jackets... I had thought that they were the same thing, saw the cheaper price and leaped on it but then realized they were different and said screw it I'll just use the Flak Jackets... Hmmm, what to do?

never leave the house without condoms, 2.00 in quarters, 40c in nickels, 40c in dimes, a quality wind-resistant lighter, and a pocket flask of your favorite spirits.

For these are the items that might just keep you form having a crappy night :p

BTW change is good for san jose's public cans, which cost 25c to use...exact change only.


edit: ok...sometimes it's good to leave the liquor at home....sometimes ;)

i've used both, and of the two, i prefer the flak jackets. full housing runs all the way to the front and rear - this leaves no open housing sections for crud to get into, other than at both ends. and if you have those sealed up well, you'll have no problems.

the FMJ work great, depending on your frame. if you have long straight runs of housing, they are good. the more bends/joins you have, the worse they are, as you will have more junctions withthe metal sleeves/housing to junk things up/introduce more friction into the system.


three bikes in the house setup with avid discs and flak jacket housing. butter smooth feel at the lever, great power, and great modulation.

all that is assuming you take the time to do a really good setup. once set and dialed though, they are great. i've seen some crappy setups; guess what? then you have crappy braking.

and for PWRDbyTRD, at your size dude, you need larger rotors, no matter what brake system you are using. at least move up to whatever the next size up for your brakes is. new rotors+new adapters won't run too much $$$, and you'll have much better power/feel/modulation.

Personally I like my Gore Ride On brake cables for use with my Avid's, but that's me.

from here:
http://www.mtbr.com/techtalks/brakes/brakesfaq.shtml

i'm of the full housing camp, with the cable ends nice and tight. i've gone as long as two years on the same set of cables. though i normally replace cables once a year just out of habit, on shifting and braking. on my geared mtb, i even run full housing for my shifting. worlds better, and i don't have to do nearly as much maintanance work.



Why would I want to run full-length housing or something like Flak Jacket or Full Metal Jackets?

Full-length housing means the housing runs continuously from the brake lever to the brake. There are a few reasons for doing this.
First, a full-length housing will protect the cable from the elements, keeping it free from dirt, rust, etc. Second, full housings will keep friction down. This sounds a little weird at first, since intuition would say that more housing means the cable is rubbing more against it, meaning more friction. But in fact, a lot of friction is introduced at the cable stops. Plastic housing ferrules bend, tighter bends happen to fit the housing into the stops, and any break in the housing is a possible entry point for water, mud, grit, etc, that will all help to add friction. This is problematic for the rust problem, too, since water stays trapped in the housing longer than it would stay on the exposed cable, meaning more rust, AND rust that’s not obvious without removing the cable.

In extreme cases, and over a long period of time, the dirt and grit that gets in there will grind that rust away, allowing new rust to take place, as well as grind away at clean cable, contributing faster to cable failure… in all, a bad situation. Full-length housing helps to prevent this.

It used to be that another problem for this type of setup was compression of the housing, resulting in loss of braking power. But newer spiral-wound housings don’t compress anywhere near as much as older, cable-style twisted wire housings did, and many are reporting that the Kevlar housings put out by Jagwire and Avid are very good protection against compression.

Another reason some people are wary of running full housing, is that in order to use the cable stops to route the housing, they need to be drilled out, and some people are wary of permanently altering the frame. But there are some after-market hydraulic cable guides available that can be used instead. Zip ties can also be used, but not everyone wants or likes to do it that way. Some custom frame-makers offer housing guides in lieu of cable stops, eliminating this problem. In practice, it’s not too hard to use a Dremel tool to open up the stops. On steel frames, it’s a good idea to paint the now-exposed metal. On aluminum bikes, it’s not a concern.

Once you’ve decided to run full housing, it is a good idea to use Teflon or plastic lined housings, and even better to use Teflon coated cables in those housings, with a drop or two of Teflon based lubricant. Reducing friction is one of the main reasons for doing this operation, so using the Teflon coated cables can only help. Most cheap, house-brand housing is already plastic lined so fancy housing isn’t necessary.

Avid’s Full Metal Jacket is an alternate method for full length housing. This uses stainless steel tubes for the straight sections of housing on the bike: the straight run down the fork, along the top-tube, and down the left seatstay. The idea is that straighter sections would cut down on friction normally encountered from bending associated with flexible housing. Whether this option really cuts down friction over a normal plastic-lined housing with Teflon coated cable isn’t clear. The cable stops still need to be drilled out for this system to be continuous or alternate means of attaching the housing must be used.
IRD’s Metawire is another alternative, using segmented aluminum housing instead of straight tubing, allowing more flexibility when routing the housing. In this case, the cable stops remain intact, and the Teflon liner-tube remains intact between stops.

Nokon’s Trac-Pearls and Konkavex systems are another interesting alternative, as both systems use alternating beads and small tubes with concave sockets at each end, so the housing system is an endless stream of ball-and-socket joints. Inside is a continuous PVC tube, meaning the system is completely sealed, and this system reportedly works very well around tight bends as well, such as that which would normally go from your brake lever to the front brake. The manufacturer also states that this system doesn’t weight more than traditional housing, so weight isn’t an issue, and the thin pvc tube seems to use normal cable-stops, so they won’t have to be drilled to run housing.

Flak Jacket housings are another Avid option using ferrules at the cable stops that allow the use of a plastic sheath over the cable, essentially protecting it from the elements in a similar fashion to the Metawire and Nokon systems, so it doesn’t require the drilling out of the cable stops to run the housing. The only difference is that the tube is not continuous with the liner of the housing; it simply slides over extensions from the housing ferrules that go through the cable stops. It’s probably a good idea to use a good amount of grease or something else to seal this joint.

I don't think that this has been mentioned, but with the majority of mechanical disc calipers, only one pad actually moves when you pull the lever. I know there are some that do, but from my expirience, most don't. All (to my knowledge) hydo ones have both pads moving. I assume this has issues with brake strength, and that the rotor is being bend slightly when the brake is applied.
Cheers