Disc pad help

redvee

I've just made the jump from V brakes to hydro discs. Now I understand there are differing grades/quality of pad. Which is best? I'm running Hayes Soles with I guess factory standard pads, when the time comes to change, which pads should I upgrade to?


TIA

whyamihere

Depends on what you want. What's wrong with the current pads? You need to know if you want more stopping power, longer life, better braking in the wet... There's no "perfect" brake pad, just ones better at certain things.

redvee

Cheers. Guess I'm gonna have to ride my bike first but stopping power will be what I'll be looking for it seems. Riding in the wet, whats that?

wwjjtt

if your riding in the uk you need sintered pads. they are a harder compound and will last loonger! resin pads wear really quickly in the mud and wet weather and i have seen people go through one pair in a day in the afan valley. i'm not sure you can get sintered for soles, but you can get magura julie pads and file them down a bit and they will fit. to be honest you wont get much difference in breeaking so your better of getting sintered.

skyliner

Hayes only make a resin pad for the Sole. Which suggests resin pads are needed to prevent rotor damage because they're semi hydro brakes.
But there are other manufacturers pads out there with a similar profile in sintered compound (can't think of the brand off the top of my head).
You could fit these with HFX-9 rotors if you're experiencing high wear rates on the std setup, but for a couple of £'s more than this'll cost you, it's possible to get a set of full hydro Shimano Deore brakes, which will run sintered pads.

tagmnbagm

Semi- Hydro?????????

Think you'll find they are hydraulic, but only have one piston so actuate from one side of the caliper only. This is why you see the rotor deflect slightly when you apply the brake.

Semi Hydro, I ask you!

skyliner

Yes semi hydraulic. They have one active, and one static piston the active one is the hydraulic side, operating on an open system principle at the lever, but with pad ajustment via a hex adjuster on the caliper.
The static side is basically a mechanical piston with adjustment via a hex key, locked in position with a grub screw making them a mix of hydro and mechanical, therefore semi hydro. And if you see the rotor flex in use, they're not correctly set up.

Full hydraulic systems, be they open or closed, will have hydraulic pistons on both sides, and will self adjust for pad wear (open) or have an adjuster on the Master cylinder reservoir (closed).
Older hayes semi hydro brakes had cable actuation, on a hydro caliper. So a mechaical lever and cable action, liked to a hydro unit.
The industry term for the hybridisation of the two technologies is "Semi Hydraulic".

tagmnbagm

Not getting the fact that your refering to these as semi hydraulic at all. the hydraulic actuation of the piston pushing the pad onto the static pad via the rota is what is giving the stopping force. And you will always get some deflection of the rota with this kind of system, if you didn't youe brakes would be rubbing very badly or locked on. There is no mechanical actuation of any kind in the static pad, only manual adjustment.
So I would define this brake as hydraulic, however basic. 8)

skyliner

It's just a terminology thing. Because the system utilises 2 different technologies, I'd class it as neither one or the other (therefore "semi hydro"). (You say potato?) The marketing dept. would disagree of course, and that's what gets printed in the mags etc.
The brake cannot be described as a fully hydraulic system, because the caliper is half mechanical.( a full hydro system comprises a lever, hose, and caliper with all pistons hydro actuated). The difference to me, is that full hydro systems are adjustable "on the fly" (or self adjustng) and hybrid, or mechanical brakes are not. ( it's standard practice in the industry to call them semi hydro)
My point on setup is that if you can "see" rotor deflection with the naked eye during operation, the brake is poorly set up. As it's possible to set up the brake inside a 1mm tolerance, while maintaining a free spinning wheel.(with deflection barely visible in operation)
Call it what you will, I'm only concerned with how it operates, and trying to improve it's performance.
If you can buy a better full hydro open system brake for not much more than it costs to upgrade the Sole to accept sintered pads, I think it's a worthwhile investment.

LaurenceGough

I find with a 100% mechanical like my current bike with one static side the rotor deflection will always be there. I have about 0.3mm on each side but the pad on the static side is worn out uneven and has more pad left towards the inside of the rotor.

So today I just made it so it drags along there slightly in hope of it evening out. Now the rest of the pad is within 0.3mm. I must say it hasn't really improved my braking much it just seems they have a limit.... Could be the pads perhaps? No matter how hard you push on the levers there's never that instant stop at slow speeds .

nicklouse

Sorry to butt in here. but can i refer you to the true semi hydro brake from some years ago.

the caliper was hydraulic but was activated by a cable.

cant remember who made it and it was not that good and was heavy.

So what is the Magura Gustav?

tagmnbagm

Sorry to butt in here. but can i refer you to the true semi hydro brake from some years ago.

Water operated brakes? surely not... I think you'l find it would taket a great deal of pressure to achieve very little compression, so water operated brakes would be worse than Hayes Soles! :?

By the way I am being sarcastic here, but its nearly 2am, an i'M STUCK AT WORK :x

skyliner

nicklouse wrote:

Sorry to butt in here. but can i refer you to the true semi hydro brake from some years ago.

the caliper was hydraulic but was activated by a cable.

cant remember who made it and it was not that good and was heavy.

So what is the Magura Gustav?

Hayes made the semi hydro brake you're referring to Nick. And it was a piece of crap, as the cable got shitted up, and it was a bugger to bleed too.

I refer to all brakes that don't have full hydraulic actuation as "semi hydraulic", so as not to mislead customers into thinking they're getting more than they bargained for.

AFAIK, The Gustav is a 4 piston mineral fluid hydraulic brake with a "floating caliper" mounting system. And hasn't changed too much since 2003? and maybe beyond that.

Unless yu're you're referring to a model I'm not familiar with?

nicklouse

2 piston on one side, but yes with the floating caliper.

my point is that if you take away the floating caliper and the extra piston it is the same as the sole.

there are mechanical disc brakes that have dual moving pads just like a hydro system.

I would describe a sole as a hydraulic single piston system.

by saying that it is semi hydro are you not impling that the other part is somehow activated differently?

i can easily see your description being valid in a shop where you can "show" the customer the similarities and differences.

skyliner

In retrospect, I should have gone with my first instinct, and said it was a piece of crap, but, relying on memory, I assumed it was a 4 pot hydro system. (a big mistake on my part, as I've now checked it out).

I accept your definition of what constitutes a "semi hydraulic" system. The fact that the actuation should be both mechanical and hydraulic seems to be the defining factor. (my definition has always been based on systems that utilise mechanical and hydraulic technologies in tandem regardless of actuation)

I still don't accept though, that a brake with half of the constituent parts being mechanical, and for the most part inactive, can be classed as "fully hydraulic". And it's misleading to describe it as such.(eg. remove half of a Magura HS33, leaving one side active, and repalce it with a fixed V brake canti and pad. Is this still a "hydraulic rim brake"? or more importantly, would you use it?)