Powered by Outside

New But Bent SRAM HS2 Rotor Opinions

PB Forum :: Mechanics' Lounge
New But Bent SRAM HS2 Rotor Opinions

 Post Message | Latest Comment
Author Message
flag Callmesb
O+
Posted: Sep 23, 2023 at 7:18 Quote
Hi, gang, cross posting from MTBR over here...

I recently bought 220/200 HS2 rotors to pair with my Code brakes. After install and during new pad bedding, I noticed a strange modulation (like and on/off feeling during consistent brake lever pressure) in the rear brake. I checked it, but couldn't find anything that seemed out of the ordinary.

After bedding, I took the bike on a shakedown and when at trail speed, the weird on/off felt much more pronounced (especially when trying to focus on slowing to avoid danger/crashing). After the ride I took the bike home, put it on a stand, and that's when I discovered my new, much more expensive 2mm HS2 was not straight. Turns out it has a pretty significant bend in it, which leads to a very disconcerting on/off feeling when braking.

I immediately contacted the shop where I bought my new rotors to see if they could initiate a warranty replacement, and they told me that bent rotors are common, and that they could not warranty them. They said the only thing they could do is bend the rotor, in hopes of straightening it.

I have installed two sets of TRP DHR EVOs on my wife's bikes, and her rotors are completely straight and work flawlessly with minimal fuss. I find it hard to swallow that I just have to accept a bent-but-brand-new $65 rotor.

Which brings me to my question...has anyone else experienced this? Are brand new rotors commonly bent from the factory? Is the shop giving me the runaround?
flag lvdukerider
Posted: Sep 23, 2023 at 10:00 Quote
Sounds like B.S. to me.
The only thing I could see them saying is that you bent them through improper instalation if they wanted to get out of warranting them for you but even that's pretty poor customer service I.M.O.
flag Callmesb
O+
Posted: Sep 23, 2023 at 11:14 Quote
lvdukerider wrote:
Sounds like B.S. to me.
The only thing I could see them saying is that you bent them through improper instalation if they wanted to get out of warranting them for you but even that's pretty poor customer service I.M.O.

Agree. I've installed plenty of rotors and I've never bent one on installation. Maybe during a crash, but never installation. I find it odd that their best answer for fixing the issue was bending it. Sure, I've straightened rotors that have been bent in a crash, but never a brand new rotor. Seems...wrong.
flag BenLow2019
Posted: Sep 23, 2023 at 15:25 Quote
Bicycle rotors are prone to bending. 2mm discs of metal can get bent at any time from manufacture to packaging to shipping, storage and distribution even before they get sold to a customer who may throw it in the backseat and maybe put groceries on top of it on the way home. In these situations the rotor hasn’t suffered a manufacturing defect so it won’t be covered under most warranty policies. Had this bent rotor been installed by the shop then the mechs would most likely discover the problem, straighten the rotor up, and give the customer a functional bike. They wouldn’t throw out the rotor and start over.
While I agree that new things should be perfect I also have to remember that I don’t live in a perfect world. In the big scheme of life, straightening a 2mm piece of metal is small potatoes.
Be advised when bringing your bike to the shop, they may charge for the time to diagnose and straighten the rotor. I’d do it myself if I were in your position.
flag lvdukerider
Posted: Sep 24, 2023 at 10:17 Quote
I bought a inexpensive rotor straightening tool off Amazon for less than $20 dollars. If all the shop is going to do is attempt to straightening it I'd save myself the trip, get the tool, and just do it myself. It's not difficult at all especially if they might find a reason to charge you anyway.
flag Callmesb
O+
Posted: Sep 24, 2023 at 18:36 Quote
The shop I bought it from is 2 hours away, so I think I’ll have my local shop bend it straight and then re-bed it.
flag Callmesb
O+
Posted: Oct 26, 2023 at 21:23 Quote
Just an update...turns out that, not only was the rear rotor bent, but it also suffered from a thickness defect from manufacturing. My LBS warrantied the rotor and the pads with SRAM, and I should have a new setup within the week. Looking forward to having my rear brake feeling as great as my front.

On a related note, changing from Code R to RSC and adding 220/203mm rotors has really really improved my braking experience, especially on long steeps. My brakes still don't feel as good as my wife's TRPs, but they're close and were much less expensive.
flag cmcgowan
Posted: Jun 11, 2024 at 11:53 Quote
Callmesb wrote:
Just an update...turns out that, not only was the rear rotor bent, but it also suffered from a thickness defect from manufacturing. My LBS warrantied the rotor and the pads with SRAM, and I should have a new setup within the week. Looking forward to having my rear brake feeling as great as my front.

On a related note, changing from Code R to RSC and adding 220/203mm rotors has really really improved my braking experience, especially on long steeps. My brakes still don't feel as good as my wife's TRPs, but they're close and were much less expensive.

It sounds like there was an issue with some of their brake track and pulsation issues on a batch of HS2 rotors. I am experiencing the same issue and having a shop warranty the rotors.
flag Turbosloth
Posted: Feb 13, 2026 at 19:57 Quote
I realize this thread is a couple years old, but some might find this interesting.
Recently purchased a couple HS2 200 mm rotors here on PB, they appeared brand new, however they have a date code of Dec of 2021. Took bike out for initial ride & everything seemed happy, (was dealing with a back injury, so no technical riding was taking place) however after a while as my riding was ramping up, doing more technical slow speed stuff, I started noticing some very faint pulsation at the lever and could feel bike pulsing at slow speeds, similar to warped rotors but different. First tried watching the rotor from top as it passes through the brake pads, but nothing to see there. Started doing a little troubleshooting and discovered that both rotors vary in thickness by mapping the rotor at 32 points, between the cutouts (using a Starrett 1/2" precision caliper) The variation is approximately 0.035" from thinnest to thickest part of rotor, then compared to a couple known good rotors and there was zero variation. The variation (thicker portion) is all on one side about 1/3 of the rotor face. I have no way of determining if this is just on one face or shared on both faces. I suppose I could use a dial indicator, but have no way to secure it for reliable measurements. My plan is to roll the dice & assume each side is equally out of tolerance and begin slowly trying to fatten it out by hand with a sanding block, and or with my orbital sander. I will update this once the rotor is either repaired or ruined.
flag aegiz
Posted: Feb 17, 2026 at 13:05 Quote
Turbosloth wrote:
I realize this thread is a couple years old, but some might find this interesting.
Recently purchased a couple HS2 200 mm rotors here on PB, they appeared brand new, however they have a date code of Dec of 2021. Took bike out for initial ride & everything seemed happy, (was dealing with a back injury, so no technical riding was taking place) however after a while as my riding was ramping up, doing more technical slow speed stuff, I started noticing some very faint pulsation at the lever and could feel bike pulsing at slow speeds, similar to warped rotors but different. First tried watching the rotor from top as it passes through the brake pads, but nothing to see there. Started doing a little troubleshooting and discovered that both rotors vary in thickness by mapping the rotor at 32 points, between the cutouts (using a Starrett 1/2" precision caliper) The variation is approximately 0.035" from thinnest to thickest part of rotor, then compared to a couple known good rotors and there was zero variation. The variation (thicker portion) is all on one side about 1/3 of the rotor face. I have no way of determining if this is just on one face or shared on both faces. I suppose I could use a dial indicator, but have no way to secure it for reliable measurements. My plan is to roll the dice & assume each side is equally out of tolerance and begin slowly trying to fatten it out by hand with a sanding block, and or with my orbital sander. I will update this once the rotor is either repaired or ruined.

uhh... assuming that your measurements revealed a maximum thickness of 2mm, a delta of 0.9mm (0.035") means that the minimum measured thickness is 1.1mm. HS2 rotors are considered worn (and to be replaced) at 1.7mm minimum thickness.

something isn't quite right here.
  • Previous Page
  • Next Page

 


Copyright © 2000 - 2026. Pinkbike.com. All rights reserved.
dv65 0.009293
Mobile Version of Website