Bought some Zees as I wanted mucho stopping power, compared to my 2 pot slx’s they just seem a bit pants.

they’ve now had lots of bleeds and tlc and still I (in my head) feel they never have the power I’d expect for a 4 pot.

so what 4 pot should I replace them with? Cheaper the better? Caliper swap? Lever swap?

Zees should be powerful but have better modulation than the 2 pot shimanos. Are you sure you’re not just mistaking modulation for lack of power?

Codes are powerful – but again with modulation – so assuming the zees aren’t faulty I don’t think they’d be an improvement.

Maguras are similar I think.

Zee are some of the most powerful brakes available. Something is wrong if this isn’t the case.

JP

Increase rotor size?

My Zees have 203mm front and 180mm rear, they are very powerful brakes.

Also are your rotors worn?

Thanks all

yeh bought the Zees as wanted the power, I’m heavy and sometimes need to rein in some speed rapido.

I’m running 203 front and rear and it’s the rear that feels the most vague, but the front has its moments.

both have sintered pads in, well bedded etc.

jumped on my other bike with single pots and they felt far more powerful and predictable with 180 rotors so it left me wondering.

Hadn’t considered the modulation point, perhaps that’s it? Maybe I drag them a bit and that manifests as wandering bite point?

When you have a sec, try swapping the front and rear rotors and see if they feel different.

Unless you have a new spare 203mm you can just stick on the rear to try.

I’ve been caught out by worn rotors with my Zees before so I always check now when the performance starts dropping off.

Contaminated rotors and/or pads? Air in the system? Pistons not working smoothly?
There’s no way that properly working Zees are less powerful than 2pot brakes.

Back worse than the front you say?

Bled on the bike? FWIW, shimano’s bleed much better vertically. Your comments so far point to possible bleeding technique improvements.

AFAIR, Shimano 4 pots are only 15 to 20% more powerful than their 2 pots, so if you were expecting eye dislodging levels of power improvements, you might need to manage your expectations too. I have Zee’s, I’m 90kgs in my birthday suit and I find them fine.

The real benefits to me are superior modulation and heat management.

Do you have organic pads in your SLX?

Sintered pads are not as sharp as organic pads when they are cold.

Thanks again all

good to ‘fact check’

brand new rotor on the rear however the brake was re bled and then new pads fitted and bedded in, i did however accidentally pop a piston out in error but I think I’ve sorted that and certainly removed any trace of contamination.

i think another bleed is in order to rule that firmly out (technique is the same as on all of my shimanos which are fine)

frustrating as riding time is really precious at the moment and brakes giving me the eeeby jeeebies is tainting some rides.

Bigyan another fair and valid point, shimano original organic I believe and zees are on Uber bike sintered now

I have some zees and the last thing in the world they lack (when working properly) is “power”. If it was me I would consider what this could have knackered:

i did however accidentally pop a piston out”

Leaks at seal? One sticky / non moving piston / air in caliper or just about anywhere.

Are they still under warranty?

2 pot SLX are pretty powerful IME and I have a set of Sram Guide 4 pot brakes on one bike and slx on another and the SLX are definitely the more powerful .