SRAM Code rear brake keeps exhibiting contamination symptoms

[ah1]

I wonder if you have 200mm rotors and you need 203mm rotors?

I don't see how - SRAM system is only 200mm (and if anything, the rotors would need to be a tad smaller, not larger). But reading this - maybe I have a bracket for 203mm rotors by mistake? It can with the bike bought new, but you never know...

 

[ah1]

PROBLEM SOLVED
So reporting back to all that are curious: starting from the end - I replaced the rear pads with Galfer Purple E-bike pads - problem solved. Squealing gone, vibrations gone, brakes are dead silent (for now, after 2 rides).

So prior to trying that: I went to SRAM booth at Sea Otter, and they confirmed the little gap on the rotor surface is typical of HS2 rotors and the alignment is fine (this is different from Centerline rotors that won't have a gap).
They also confirmed the adapter was the correct one BUT they suggested trying the SRAM 20p-2 adapter which attaches differently - instead of bolt going through both caliper and adapter like came with my bike, on the 20p-2 one bolt attaches the adapter to bike, and another attached caliper to adapter. They also suggested changing the hose attachment angle (be careful with that not to open too much, a half turn is enough). I tried both and it didn't help.
More importantly they did take a look and rule out contamination. So after trying the above, I tried the different pads and problem gone! Now, what I don't know is had I kept my old adapter with the Galfers would it have still solved the issue - but I'm not experimenting anymore, I'm just glad the brakes are back to great!

On a final note - I did previously try SRAM sintered and MTX Gold and neither helped. It could be that the Galfers are made of different material, that handles what is probably my over zealousness of using the rear brake. So not saying Galfers are better pads, just that I've been trying the wrong pad material in the rear that doesn't suit my riding style. And I know people have complaints about the Codes but honestly they feel bulletproof right now!

Thanks all that posted helpful and detailed suggestions!!

 

[Mikerb]

Glad you got it sorted. I have Code RSCs on both my bikes and they are brilliant. One is using HS2 rotors the other centreline. I use SRAM sintered pads or RaceTi.....no real difference except price.
My experience is that the front brake rarely needs attention but the rear needs the calliper/ pistons cleaning fairly regularly to keep it sweet. I put that down to the fact the calliper is mounted horizontally and allows mud and dust to enter the top of the calliper. It is also the case that because of the route the dot 5 has to take to reach opposite sides of the calliper the wheel side pistons tend to push out further than the outside pistons. So as the pads wear....or you change contact point the calliper can need realignment. Easily done...just loosen the adapter bolts....apply the brake and retighten the bolts. Any incorrect alignment will cause rotor squeal . So maintenance is the answer.

 

[Utah Rider]

Thanks for the update!

 

[ah1]

Glad you got it sorted. I have Code RSCs on both my bikes and they are brilliant. One is using HS2 rotors the other centreline. I use SRAM sintered pads or RaceTi.....no real difference except price.
My experience is that the front brake rarely needs attention but the rear needs the calliper/ pistons cleaning fairly regularly to keep it sweet. I put that down to the fact the calliper is mounted horizontally and allows mud and dust to enter the top of the calliper. It is also the case that because of the route the dot 5 has to take to reach opposite sides of the calliper the wheel side pistons tend to push out further than the outside pistons. So as the pads wear....or you change contact point the calliper can need realignment. Easily done...just loosen the adapter bolts....apply the brake and retighten the bolts. Any incorrect alignment will cause rotor squeal . So maintenance is the answer.

Yes agreed. I do maintain, clean and realign monthly (needs to be done regardless of squealing). In my case it would help for the first hour of the ride, then squealing would return (with previous pads) even if alignment is kept and nothing rubbing. I will say the right pad material most likely depends on rider, bike, etc so each can be different - My other bikes also have Code RSCs and no issues for years.