disc brakes br-m446 pads and disc rotor resin only ?

swod1

On my trek 4500, I've had from new shimano hydraulic disc brakes, model br-m446.

Since the bike was new they have always been ok but never had much bite to them but have stopped me quite well.

The bike is over a year old and after breaking my back wheel quite badly last week, the bike got a proper check over.

It also had a silver service in evans cycles back in may.

I looked at the pads and there is not much wear to say I've done nearly a thousand miles on the bike in all sorts of weather conditions.

Then i noticed stamped on the disc rotors of the original wheels is "resin only".

What does this mean and could this be as well as my lack of skill on the bike a contributing factor to me coming off the bike last week ?

I've started a fresh with a new rotor on the new back wheel and should i bin the front disc and install a new one and some better brake pads ?

advice welcome.

thelonegroover

Depends if it’s a recommendation or a stipulation. I thought all brake rotors were stainless steel; resin will work better but may not last as long as metallic sintered.

cooldad

The rotors make no difference - all cheap Shimano say resin only - I have them on a few bikes and use all sorts of pads. Theoretically the rotors may wear quicker, but one day the sun is going to explode anyway...

swod1

cooldad wrote:

The rotors make no difference - all cheap Shimano say resin only - I have them on a few bikes and use all sorts of pads. Theoretically the rotors may wear quicker, but one day the sun is going to explode anyway...

I just think the brakes could be so much better than they are at the moment which is why i was asking if i should bin the pads and front disc and buy something better ?

I was looking at upgrading the front rotor to 180mm and replacing the pads all round to sintered or kelvar for a better feel.

cooldad

Where the brakes better in the past? As I said, rotors make no difference, although obviously going bigger does.
Sintered or kevlar will not necessarily give better feel, if anything organic will give the best feel and stopping power.
OE Shimano resin pads are a bit rubbish, so try some Superstar pads and clean the rotors.

POAH

using metal pads on resin only pads will make them wear out quicker according to Shimano. there are two types of rotor for the cheaper end, the difference seems to be the rotors that can use metal pads are hardened

cooldad

POAH wrote:

using metal pads on resin only pads will make them wear out quicker according to Shimano. there are two types of rotor for the cheaper end, the difference seems to be the rotors that can use metal pads are
hardened

You may want to read that again.
As I said, they may wear quicker, but one day the sun is going to explode anyway...
Mine are five years old. Still going strong.

swod1

cooldad wrote:

Where the brakes better in the past? As I said, rotors make no difference, although obviously going bigger does.
Sintered or kevlar will not necessarily give better feel, if anything organic will give the best feel and stopping power.
OE Shimano resin pads are a bit rubbish, so try some Superstar pads and clean the rotors.

The brakes felt good originally when i bought the bike as it was the first time i'd ever had hydraulic brakes on a bike but as i've ridden it more, i think they could have a better feel and bite.

I'm using a new shimano sm-rt66 rotor on the rear which seems slightly better with the same pads but not great.

The front could be a lot better, maybe i need to up the disc size because i'm a big unit and 160mm be a little small and going up to 203mm front disc be over kill on a hard tail bike ?

thelonegroover

If, as you say the brakes were OK when new, then clean the disks with IPA and fit better quality resin pads.

swod1

Thelonegroover wrote:

If, as you say the brakes were OK when new, then clean the disks with IPA and fit better quality resin pads.

yes they were, i never had disc brakes before so thought they was great but a lot of riding later i think they can be better.

I think i'm just going to change the pads, i've already swapped the rear disc as i had to buy a new wheel so bought a new rotor at the same.

after riding to and from work today in the rain, a pad change cant come soon enough that squeal is starting be annoying now.

Are sintered pads only recommended in the winter ?

thelonegroover

I wouldn’t say sintered pads are only for winter. Just as organic pads aren’t just for summer. But if you ride a lot in wet gritty conditions sintered will last a lot longer. They will also tend to squeal more than organic. From what you say, I’d make sure your current rotors are clean and fit some decent organic pads.

Having said that, lots of members on here seem to like to spend money when they don't really need to. (I am from Yorkshire).

The Rookie

Also not a good idea to use sintered pads for long decents (Alpine style), they have a bit of a cliff in the friction curve, get them too hot and brake performance falls off very rapidly.

POAH

cooldad wrote:

POAH wrote:

using metal pads on resin only pads will make them wear out quicker according to Shimano. there are two types of rotor for the cheaper end, the difference seems to be the rotors that can use metal pads are
hardened

You may want to read that again.
As I said, they may wear quicker, but one day the sun is going to explode anyway...
Mine are five years old. Still going strong.

you might want to read what I wrote too

Chunkers1980

But again real world experience which is impossible for you to have says it doesn't make a jot of difference.

POAH

Chunkers1980 wrote:

But again real world experience which is impossible for you to have says it doesn't make a jot of difference.

not arguing that nor saying am I saying what shimano say is gospel