Mechanics Quick Question Thread [Ask Questions Here]

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Mechanics Quick Question Thread [Ask Questions Here]
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Posted: Jul 6, 2022 at 5:44 Quote
BryanBobo wrote:
Hi All,

I’ve really been struggling with my SRAM Code RS brakes for an entire season now. ... Aside from that, any other things worth checking out before giving up entirely?

Assuming you know how to bleed brakes correctly and follow the normal service steps there's a few things I'd suggest that may help.

(1) de-gas the DOT fluid before bleeding the brakes
(2) lubricate the pistons and then verify that all pistons move smoothly
(3) complete the final steps of the SRAM bleed procedure in reverse order (remove the bleeding edge tool last vice first which allows you to put pressure in the system and pop out the device without losing any fluid)
(4) center the calipers over the rotors by using the "paper between the pads and rotor" trick

Good luck.

Posted: Jul 6, 2022 at 6:07 Quote
BryanBobo wrote:
Hi All,

I’ve really been struggling with my SRAM Code RS brakes for an entire season now. They just… suck. They are loud under heavy braking (they almost sound like the pad is entirely worn down sometimes) & have poor stopping power. I’ve tried swapping pads multiple times while also ensuring I’m bedding the brakes appropriately (thinking maybe they were contaminated), multiple bleeds, still no luck.

The final thing I was going to try before changing to new brakes entirely was upgrading from the stock centerline rotors to the HS2 rotors. Aside from that, any other things worth checking out before giving up entirely?

This may sound silly, but are the rotors on in the right direction? One of mine was installed backwards (from factory) and I never noticed it until i upgraded to the Code RS. Flipped the rotor that was in the wrong direction, and re-bedded on the next run then never had an issue again.

Posted: Jul 6, 2022 at 6:12 Quote
I'm not a fan of Sram brakes in general, but Codes should lock up a front wheel with ease. If they aren't something is wrong.

New pads and clean rotors should solve any contamination issues. Cleaning the rotor with IPA is fine, you shouldn't need to do more than that. If you want to be extra sure, you could give the rotors a light sanding and then clean with IPA again. Don't do anything drastic like set fire to them, this only ever makes it worse.

90% of the time, mysterious lack of braking power (when the pads are new) comes from poor caliper alignment over the rotor. If the rotor contacts one pad before the other, you will lose braking performance and increase noise. This would be the first thing I'd check on your bike. Getting the calliper correctly aligned is a total pain in the arse, and even most bike shops do a really poor job of this. Get it perfect, and I suspect you will see a good increase in braking performance.

Also, I never spray fancy "brake cleaner" sprays on my brakes. They often have "pad conditioning compounds" in them to reduce noise, which are essentially just light oil Facepalm

The only cleaner I ever put anywhere near my brakes is IPA. People often comment on how amazingly powerful my brakes feel compared to theirs. All I use is standard pads, proper alignment, and IPA.

Posted: Jul 6, 2022 at 11:23 Quote
Hey all,
I just got around to doing my frame bearings on my GT force, I pulled off my Seatstay's with little issue, but i ran into a small issue with the main rocker pivot and the main lower pivot. I'm not entirely sure how to remove or loosen these 2 bolts/areas,

There was a torx (t25) that screwed into the main pivot. I think that's just a (dust cover) for the pivot?
I have no idea how to get this bolt out, any help is appreciated!


Posted: Jul 6, 2022 at 11:57 Quote
MTBrandonLee wrote:
Hey all,
I just got around to doing my frame bearings on my GT force, I pulled off my Seatstay's with little issue, but i ran into a small issue with the main rocker pivot and the main lower pivot. I'm not entirely sure how to remove or loosen these 2 bolts/areas,

There was a torx (t25) that screwed into the main pivot. I think that's just a (dust cover) for the pivot?
I have no idea how to get this bolt out, any help is appreciated!
Not trying to be a dick, but have you read the owner’s manual?

Not sure if it’s the right one but I found this for the 2019 model. https://www.gtbicycles.com/media/wysiwyg/pdfs/GT_Force_Sensor_OMS_web.pdf

When in doubt RTFM.

Posted: Jul 6, 2022 at 12:10 Quote
Nobble wrote:
MTBrandonLee wrote:
Hey all,
I just got around to doing my frame bearings on my GT force, I pulled off my Seatstay's with little issue, but i ran into a small issue with the main rocker pivot and the main lower pivot. I'm not entirely sure how to remove or loosen these 2 bolts/areas,

There was a torx (t25) that screwed into the main pivot. I think that's just a (dust cover) for the pivot?
I have no idea how to get this bolt out, any help is appreciated!
Not trying to be a dick, but have you read the owner’s manual?

Not sure if it’s the right one but I found this for the 2019 model. https://www.gtbicycles.com/media/wysiwyg/pdfs/GT_Force_Sensor_OMS_web.pdf

When in doubt RTFM.

You're good. Preciate the help Smile

TBH didn't even think about the manual...ape brain moment. Big Grin

Posted: Jul 7, 2022 at 2:10 Quote
Nobble wrote:
MTBrandonLee wrote:
Hey all,
I just got around to doing my frame bearings on my GT force, I pulled off my Seatstay's with little issue, but i ran into a small issue with the main rocker pivot and the main lower pivot. I'm not entirely sure how to remove or loosen these 2 bolts/areas,

There was a torx (t25) that screwed into the main pivot. I think that's just a (dust cover) for the pivot?
I have no idea how to get this bolt out, any help is appreciated!
Not trying to be a dick, but have you read the owner’s manual?

Not sure if it’s the right one but I found this for the 2019 model. https://www.gtbicycles.com/media/wysiwyg/pdfs/GT_Force_Sensor_OMS_web.pdf

When in doubt RTFM.

^^^^ What he said
But also, it looks like an expanding collet design. So after you remove the t25, you are likely to have to loosen a further bolt that lives underneath it. Looking at the etching on your frame, I think it's a 6mm allen key you need. But yeah, getting hold of a copy of the manual should answer all your questions

Posted: Jul 7, 2022 at 3:49 Quote
gabriel-mission9 wrote:
I'm not a fan of Sram brakes in general, but Codes should lock up a front wheel with ease. If they aren't something is wrong.

New pads and clean rotors should solve any contamination issues. Cleaning the rotor with IPA is fine, you shouldn't need to do more than that. If you want to be extra sure, you could give the rotors a light sanding and then clean with IPA again. Don't do anything drastic like set fire to them, this only ever makes it worse.

90% of the time, mysterious lack of braking power (when the pads are new) comes from poor caliper alignment over the rotor. If the rotor contacts one pad before the other, you will lose braking performance and increase noise. This would be the first thing I'd check on your bike. Getting the calliper correctly aligned is a total pain in the arse, and even most bike shops do a really poor job of this. Get it perfect, and I suspect you will see a good increase in braking performance.

Also, I never spray fancy "brake cleaner" sprays on my brakes. They often have "pad conditioning compounds" in them to reduce noise, which are essentially just light oil Facepalm

The only cleaner I ever put anywhere near my brakes is IPA. People often comment on how amazingly powerful my brakes feel compared to theirs. All I use is standard pads, proper alignment, and IPA.
This is what worries me about the new prototype brakes from SRAM, https://youtu.be/JGT0EDlznk8?t=227
If you look at the timestamp in that pinkbike pits video you see that you cannot look in them from the top. No clear view on the pistons and pads.
With open tops it is so easy to see if there is a lazy piston or the caliper isn't setup parallel with the disc and if the gaps are equal left to right. With out a long baseline view it hard to see if it is off or not.

It does look like a super stiff caliper with plenty of material for a heat sink, so that is probably nice. But I can already hear all the whines and turkey gobbles in the Bikepark of all the misaligned brakes. lol

Posted: Jul 9, 2022 at 8:34 Quote
Hey- putting together a bike right now and as shown in the photo due to the size of my brake disk the brake itself cant be attached to the frame- Is there some sort of extension piece I could get or do I have to decrease the size of the disk?-

Posted: Jul 9, 2022 at 8:40 Quote
jackoconnor wrote:
Hey- putting together a bike right now and as shown in the photo due to the size of my brake disk the brake itself cant be attached to the frame- Is there some sort of extension piece I could get or do I have to decrease the size of the disk?-

yup, you need to figure out what size max rotor your frame can run and them what size rotor you are running and there will be a adapter for it it will be someone like PM180/203 or something like that

Posted: Jul 9, 2022 at 8:50 Quote
PM160/180 here probably

Posted: Jul 9, 2022 at 8:57 Quote
TibZ wrote:
PM160/180 here probably

Seconded.

Posted: Jul 9, 2022 at 21:55 Quote
Anyone purchase anything off of TITLES upcyceling program? if so what defects did you component come with?

Posted: Jul 10, 2022 at 13:47 Quote
Hello, I have a ZEB ultimate 170mm. I happened to try 2 other ZEBs , a ZEB Select and a ZEB R.

The first thing I notice is how much more eager and free these other forks are to compress, while the other guys are shocked first by my lower pressure, and then by how much stiffer my fork feels to squeeze compared to theirs at higher pressures.
These are parking lot squeeze tests.
My fork has always been this way, also did a lower leg service this week. I use motorex supergliss 100k as a lube.
Anything I should check?

Posted: Jul 10, 2022 at 13:49 Quote
Air spring service

(Too much grease in there might explain your issue)


 
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