Mechanics Quick Question Thread [Ask Questions Here]

PB Forum :: Mechanics' Lounge
Mechanics Quick Question Thread [Ask Questions Here]
Author Message
flag chickenrunz
Posted: Jan 25, 2020 at 0:49 Quote
I took the whole contraption off the bike and gave the caliper a good shake and it started working. So I rebled them. I took the other one off the bike and also gave it a good shake. They are now better than new. I cannot believe that.

Anyway I have 2 questions -

1. Will i need to bleed them every year? If so I'm selling them and sticking with Shimano. If they will like forever like Shimanos I will stick them on wife's bike.

2. The bottle of DOT fluid that i bought just for this brakes - can they be stored for a few years or will they degrade?

Thanks
flag chickenrunz
Posted: Jan 25, 2020 at 3:06 Quote
I took the whole contraption off the bike and gave the caliper a good shake and it started working. So I rebled them. I took the other one off the bike and also gave it a good shake. They are now better than new. I cannot believe that.

Anyway I have 2 questions -

1. Will i need to bleed them every year? If so I'm selling them and sticking with Shimano. If they will like forever like Shimanos I will stick them on wife's bike.

2. The bottle of DOT fluid that i bought just for this brakes - can they be stored for a few years or will they degrade?

Thanks
flag ajax-ripper
Posted: Jan 25, 2020 at 6:01 Quote
A well bled sram brake will last a season or two without requiring a rebleed, whereas a Shimano brake will require a bleed atleast once or twice every season.

That said, the bleed procedure for a sram brake is much more in depth and if not completed properly will cause the breaker to feel worse then it did prior to service. The steps I followed in the shop where as followed:

1: fill two syringes with fluid, one should be 2/3 - 3/4 full the other about 1/4 - 1/3 full. Both syringes should be purged of air.

2. Connect both syringes to the system, the more full of the two goes on the caliper.

3. Push fluid from the caliper to the lever and then back, repeat this a few times, you should end this with the caliper syringe being about as full as it was when you started.

4. Pull the lever to the bar and hold it there with a ziptie or toestrap.

5. Pull vacuum on the caliper syringe to pull any air out, tapping on the caliper can help get any air out.

6. Hold the lever against the bar with your hand, apply pressure to the caliper syringe and allow it to push the lever out. Once fully extended remove the caliper side syringe and close the bleed Port.

7. Pull vacuum on the lever, pulling the lever on and out can help get bubbles out.

8. Once satisfied pressure up the syringe, remove it and install the plug.

Remember that they won't ever feel like a Shimano brake, they will always have softer engagement with more pull from lock to release.
flag riish
Posted: Jan 25, 2020 at 6:17 Quote
chickenrunz wrote:
I took the whole contraption off the bike and gave the caliper a good shake and it started working. So I rebled them. I took the other one off the bike and also gave it a good shake. They are now better than new. I cannot believe that.

Anyway I have 2 questions -

1. Will i need to bleed them every year? If so I'm selling them and sticking with Shimano. If they will like forever like Shimanos I will stick them on wife's bike.

2. The bottle of DOT fluid that i bought just for this brakes - can they be stored for a few years or will they degrade?

Thanks

I usually hang my brakes up from the workshop roof with the lever pulled before bleeding when I’m doing full bike overhauls.
That and tapping on the caliber and lever body with a plier handle works really well for getting a good bleed from them.
flag Thepureface
Posted: Jan 25, 2020 at 6:22 Quote
potato wrote:
Thepureface wrote:
Wow that was an easy diagnosis- while on the topic. What causes a blown damper?

Thanks guys.

There is a good chance that seals are worn, but what i have often seen is nitrogen leaking out of the ifp.
The nitrogen is now mixed with the oil and the damper won't work with the froth.
This is why sometimes the shock will work a bit at first and after a few cycles just blows thru as the oil and n2 froth up.

A rebuild will fix this pretty easy.

I have my own nitrogen needle, and access to mostly spent industrial n2 bottles.
I only need a couple hundred psi.
Drain oil, carefully set and refill.
Fill damper with oil and close it up, charge the ifp with correct n2 psi.

Shock makes a lot less squishing noises, and damper is much more sensitive after this service.

Rp23 ifp rebuild, videos on youtube are helpful.

Thanks appreciate it. I will take a look but to be completely honest, the dampers seem a bit intimidating to rebuild.
flag talkingspoon
Posted: Jan 25, 2020 at 8:36 Quote
riish wrote:
chickenrunz wrote:

2. The bottle of DOT fluid that i bought just for this brakes - can they be stored for a few years or will they degrade?

Thanks

That open bottle is only good for about 6 months now as dot fluid is hydroscopic (absorbs moisture) and will lower the boiling point
flag cyberoptixs
Posted: Jan 25, 2020 at 8:52 Quote
i have a YBN 10 speed chain and i need a chain pin for it, will a shimano 10 speed chain pin work?
flag ajax-ripper
Posted: Jan 25, 2020 at 9:04 Quote
cyberoptixs wrote:
i have a YBN 10 speed chain and i need a chain pin for it, will a shimano 10 speed chain pin work?
Yes, however a quick link is also not a bad idea
flag cyberoptixs
Posted: Jan 25, 2020 at 9:08 Quote
ajax-ripper wrote:
cyberoptixs wrote:
i have a YBN 10 speed chain and i need a chain pin for it, will a shimano 10 speed chain pin work?
Yes, however a quick link is also not a bad idea

yea i know i have one on there already but what im wanting to do is reattach the links i took off, bought a new frame and dont want to buy a new chain since it only a few months old
flag ajax-ripper
Posted: Jan 25, 2020 at 9:11 Quote
cyberoptixs wrote:
ajax-ripper wrote:
cyberoptixs wrote:
i have a YBN 10 speed chain and i need a chain pin for it, will a shimano 10 speed chain pin work?
Yes, however a quick link is also not a bad idea

yea i know i have one on there already but what im wanting to do is reattach the links i took off, bought a new frame and dont want to buy a new chain since it only a few months old
Don't be a cheap c*nt.
flag cyberoptixs
Posted: Jan 25, 2020 at 9:28 Quote
ajax-ripper wrote:
cyberoptixs wrote:
ajax-ripper wrote:

Yes, however a quick link is also not a bad idea

yea i know i have one on there already but what im wanting to do is reattach the links i took off, bought a new frame and dont want to buy a new chain since it only a few months old
Don't be a cheap c*nt.

Gotta be man just dished out some.big bucks for a new frame
flag seraph
Posted: Jan 25, 2020 at 9:32 Quote
A quick link will work better for a YBN.
flag chickenrunz
Posted: Jan 25, 2020 at 9:47 Quote
ajax-ripper wrote:
A well bled sram brake will last a season or two without requiring a rebleed, whereas a Shimano brake will require a bleed atleast once or twice every season.

That said, the bleed procedure for a sram brake is much more in depth and if not completed properly will cause the breaker to feel worse then it did prior to service. The steps I followed in the shop where as followed:

1: fill two syringes with fluid, one should be 2/3 - 3/4 full the other about 1/4 - 1/3 full. Both syringes should be purged of air.

2. Connect both syringes to the system, the more full of the two goes on the caliper.

3. Push fluid from the caliper to the lever and then back, repeat this a few times, you should end this with the caliper syringe being about as full as it was when you started.

4. Pull the lever to the bar and hold it there with a ziptie or toestrap.

5. Pull vacuum on the caliper syringe to pull any air out, tapping on the caliper can help get any air out.

6. Hold the lever against the bar with your hand, apply pressure to the caliper syringe and allow it to push the lever out. Once fully extended remove the caliper side syringe and close the bleed Port.

7. Pull vacuum on the lever, pulling the lever on and out can help get bubbles out.

8. Once satisfied pressure up the syringe, remove it and install the plug.

Remember that they won't ever feel like a Shimano brake, they will always have softer engagement with more pull from lock to release.

Thanks. Hmm I didn't zip tie the lever... Still works amazing though. It just needed to be shaken not stirred.
flag chickenrunz
Posted: Jan 25, 2020 at 9:48 Quote
talkingspoon wrote:
riish wrote:
chickenrunz wrote:

2. The bottle of DOT fluid that i bought just for this brakes - can they be stored for a few years or will they degrade?

Thanks

That open bottle is only good for about 6 months now as dot fluid is hydroscopic (absorbs moisture) and will lower the boiling point

Just as well I used nearly half the bottle trying to bleed the pair! Lol.
flag seraph
Posted: Jan 25, 2020 at 10:04 Quote
I bled my SRAM brakes with the new Muc Off high performance fluid and it's been really good. It has a much higher boiling point than regular dot fluid.

 


Copyright © 2000 - 2024. Pinkbike.com. All rights reserved.
dv42 0.027319
Mobile Version of Website