Upgrading from 160mm rotors

[droo]

Fill up your water bottle

Remove pads

Spray water on pads

Rub pads together

Rinse pads

Repeat until shinyness is gone

Replace pads

Find a hill

Sprint down

Brake hard, but don't stop

Repeat until the increase in power plateaus

Leave to cool.

 

You should get a decent improvement from this, if not replace pads and try again.

[MORNE]

1 hour ago, droo said:

Fill up your water bottle

Remove pads

Spray water on pads

Rub pads together

Rinse pads

Repeat until shinyness is gone

Replace pads

Find a hill

Sprint down

Brake hard, but don't stop

Repeat until the increase in power plateaus

Leave to cool.

 

You should get a decent improvement from this, if not replace pads and try again.

instructions unclear.

brake pads now smell like Rehadrate and coke haf-n-half

[Trance Dance]

In my experience, bigger is better! I went to 203mm up front and brakes went from good to great! My wife's bike was originally 180f and 160r. Putting a 180mm  rotor on the rear of her trail bike made a noticeable difference. She weighs like 56kg and noticed the difference. 

[love2fly]

7 hours ago, BenGraham said:

Would probably help to identify the brakes. Also it's worth noting that you get resin and metallic brake pads and they can have a significant difference on braking performance. Metallic is apparently stronger but you have to have rotors that allow them as metallic pads on rotors designed for resin pads is going to massively increase wear.

An important thing to understand is that on a hardtail something like 70% of your brake force is coming from the front so that's where you'll see the most significant gains. I run a 180mm front and a 160mm rear and find this to work well. I would say 203mm is probably excessive outside of DH. That said I recently replaced my ageing brakes and the new ones are better but it's not so much outright power as it is modulation (this matters but it's hard to quantify). They actually felt slightly weaker (or maybe just less apparent bite) at first but I think they're bedding in now and they seem to be getting better.

Also a good bleed is important. My brakes were getting very spongy so I bled them (poorly) and that's how I messed up my rear brake and ended up replacing them. A brake bleed is cheap and effective sometimes. And messing it up yourself can be expensive.

Anyway these are my thoughts.

I've always switched from resin to metallic pads and have sold bike components to LBS and have NEVER heard that you need different rotors. Even lower end Shimano brakes seem to be sharper than Sram but having said that I weigh 100kg and with 180mm in front I stop using 1 finger with Level TLM's.

PS I was told metallic pads chow up rotors. Am on 3rd front rotors and 2nd rear in over 10,000km

[HenryS]

54 minutes ago, love2fly said:

I've always switched from resin to metallic pads and have sold bike components to LBS and have NEVER heard that you need different rotors. Even lower end Shimano brakes seem to be sharper than Sram but having said that I weigh 100kg and with 180mm in front I stop using 1 finger with Level TLM's.

PS I was told metallic pads chow up rotors. Am on 3rd front rotors and 2nd rear in over 10,000km

Here is an example of a rotor that should only be used with resin pads.
https://www.evobikes.co.za/product/shimano-center-lock-disc-brake-rotor-160-mm-sm-rt30-resin/

[BenGraham]

1 hour ago, love2fly said:

I've always switched from resin to metallic pads and have sold bike components to LBS and have NEVER heard that you need different rotors.

It's literally printed on some rotors. I've seen it with my own eyes.

 

Edited May 12, 2021 by BenGraham

[StevieG]

16 hours ago, Hairy said:

Your brakes def. need a bleed!

Here is a interesting experiment for. Take a toe strap or some electrical tape. With the bike standing on the ground, wheels horizontal, pull the lever as far back as it will go and then tape or tie the lever into this position. Repeat for the other one.

Leave it till the next day, remove the tape and test the feel of the levers then.

Will have to try that later, but what would the result be if I may ask?

[100Tours]

Do the bleeding and bedding in, but at the end of the day it depends on your riding style. I'm 6', 82kgs and I have gone 180mm on all my bikes. it just feels better.

[RJClegg]

I'll bed in the pads this weekend and then go to 180mm rotors front and back. Will update here once done for future reference to others. 

[Headshot]

18 hours ago, Hairy said:

Not running properly bled SRAM brakes that is ... a properly bled SRAM brake = awesomeness

Maybe but then you still have *** power and the need for a horrid brake fluid bleed again soon. I haven't even got my 785 XTs running perfectly yet but they are in another league to my *** Guides.

[LOCO4360]

I fully agree with STOKE and HAIRY - I had a hardtail where the braking was poor even with Shimano Deores and bedding in the pads properly did the world of good... 

Sand them down with some 800grit paper just so the glaze is gone and then do a bed in like GMBN suggests (find a hill like Stoke said) and when you think you are done - do it again lol

As for a bleed I would say this may or may not be required but in order to improve the bite you should advance you pads a little. with the wheel out pull the lever a little to push to pads out a little more, wheel back and test to see if they bite sooner when pulling the lever. This could make a huge difference even when bedding the pads. 

Failing all this, if you have not done a bleed before and you are just going to give it a try, don't - take it to your LBS and let them bleed it - if the mess it up they have to sort it out. 

BTW - changed to 180 front and rear and with a bleed and pads advanced worked awesome (same brakes on my full sus now) and I ride hard and even when I was 96kg I had even power.  

[Quagga]

18 hours ago, droo said:

Fill up your water bottle

Remove pads

Spray water on pads

Rub pads together

Rinse pads

Repeat until shinyness is gone

Replace pads

Find a hill

Sprint down

Brake hard, but don't stop

Repeat until the increase in power plateaus

Leave to cool.

 

You should get a decent improvement from this, if not replace pads and try again.

Is the brake hard now what caused the shinyness in the first place?
I bed them in slowly as I read you do not want them to get hot, hot is what causes the shinyness

 

Play it cool. If brake pads overheat when new, it can permanently change the underlying structure of the materials they’re made from – and not for the better. Until the brakes are fully bedded, drivers should avoid the heavy braking that leads to overheating: whether it’s because they’re braking from high speed, towing heavy loads, or driving on steep terrain.

[Steady Spin]

I've always broken in brakes from little over walking speed to almost stopping and using wet pads. Repeat about 10 times on a good slope. Sometimes even hard and fast but never locking up the brakes.

From research it is also what Park Tool recommends. 

 

[The Ouzo]

Shimano recommends 5 or 6 repeated hard braking from around 15km/h to just before stopping, but never stopping, then up the speed to 20km/h and repeat.

Do one brake at a time.

 

It worked for my rear brake, but I suspect the front brake got a little contaminated as its not biting as well as the rear.

[dasilvarsa]

To Decontaminate Disks Take Disk Off the Wheel

Shield Car Wash Neat and a Nail Brush 15 Minutes per Side

Work The Dirt out of the Holes.

Be Careful Not to bend the Disks.

Do the same to the Pads but Only 2 Minutes.

If the Back Brake Can Lock the Back Wheel on Tar It's Working Good.

A bit more difficult to test the Front (OTB).

[W@nted]

Interesting topic. I have purchased new pads for my brakes, but how do I know the rotors are still in good condition?