Mechanics Quick Question Thread [Ask Questions Here]

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Mechanics Quick Question Thread [Ask Questions Here]
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Posted: Jan 23, 2020 at 11:29 Quote
scjeremy wrote:
Should I clean my old rotors before bedding in new brakes? Same brakes / pads and the rotors were not contaminated. Can I just bed them in on top of the pad material already on the rotor?

No don't clean them, just bed them in as per normal.

Posted: Jan 23, 2020 at 13:50 Quote
wrote:
[Quote]Cane creek makes an adjustable angle set but I’ve heard it’s prone to creaking. Works components makes a solid angle set in 1 degree increments. I’ve used one and it was flawless.

sosburn wrote:
+1 for the Works angleset.
cheaper than cane creek as well iirc

ThanksSalute

Posted: Jan 23, 2020 at 14:36 Quote
scjeremy wrote:
Should I clean my old rotors before bedding in new brakes? Same brakes / pads and the rotors were not contaminated. Can I just bed them in on top of the pad material already on the rotor?

i don't know whether this is a goer or not so don't take it as advice. i have never cleaned or replaced rotors when replacing brakes, brake pads, different brand, etc. just plug and play. i'm not a downhill world cup racer however ...

Posted: Jan 23, 2020 at 15:34 Quote
chickenrunz wrote:
scjeremy wrote:
Should I clean my old rotors before bedding in new brakes? Same brakes / pads and the rotors were not contaminated. Can I just bed them in on top of the pad material already on the rotor?

i don't know whether this is a goer or not so don't take it as advice. i have never cleaned or replaced rotors when replacing brakes, brake pads, different brand, etc. just plug and play. i'm not a downhill world cup racer however ...
Didn’t touch the rotors. Ten hard slow downs each front and back on a long hill and both ends are locking up at will.

Posted: Jan 23, 2020 at 15:44 Quote
scjeremy wrote:
chickenrunz wrote:
scjeremy wrote:
Should I clean my old rotors before bedding in new brakes? Same brakes / pads and the rotors were not contaminated. Can I just bed them in on top of the pad material already on the rotor?

i don't know whether this is a goer or not so don't take it as advice. i have never cleaned or replaced rotors when replacing brakes, brake pads, different brand, etc. just plug and play. i'm not a downhill world cup racer however ...
Didn’t touch the rotors. Ten hard slow downs each front and back on a long hill and both ends are locking up at will.

If you are sticking with existing pad compound there's no real issue. However in some circumstances switching from organic to metallic compound pass without sanding the rotor can cause horrific noises.

Posted: Jan 23, 2020 at 16:13 Quote
There's never harm in taking some fine emery paper / cloth to the rotors if you change compounds, but it's rarely necessary.

Posted: Jan 24, 2020 at 4:24 Quote
guys I have a cove hooker bike and there is a problem with it.

The rear shock is a fox rp23.

The problem is that it just blows through travel and the pedal assist doesnt seem to work.

Anyways do you think I could change the rear shock to something that is firmer? Maybe something like the monarch shock that has different tunes?

I also have a pslope and it has a monarch with an mm tune. It also has a very different rear suspension I know.

How to know what tune, and what size shock would fit?


Or is the fox rp23 an okay shock and maybe just get it rebuilt? Im a little worried this shock has always had a problem since day 1 when I got the frame. New - old stock

Posted: Jan 24, 2020 at 7:45 Quote
Thepureface wrote:
guys I have a cove hooker bike and there is a problem with it.

The rear shock is a fox rp23.

The problem is that it just blows through travel and the pedal assist doesnt seem to work.

Anyways do you think I could change the rear shock to something that is firmer? Maybe something like the monarch shock that has different tunes?

I also have a pslope and it has a monarch with an mm tune. It also has a very different rear suspension I know.

How to know what tune, and what size shock would fit?


Or is the fox rp23 an okay shock and maybe just get it rebuilt? Im a little worried this shock has always had a problem since day 1 when I got the frame. New - old stock
blown damper. It will need rebuilding and possibly new parts like shims. Send it to suspension werx or vorsprung

Posted: Jan 24, 2020 at 7:49 Quote
spaceofades wrote:
Thepureface wrote:
guys I have a cove hooker bike and there is a problem with it.

The rear shock is a fox rp23.

The problem is that it just blows through travel and the pedal assist doesnt seem to work.

Anyways do you think I could change the rear shock to something that is firmer? Maybe something like the monarch shock that has different tunes?

I also have a pslope and it has a monarch with an mm tune. It also has a very different rear suspension I know.

How to know what tune, and what size shock would fit?


Or is the fox rp23 an okay shock and maybe just get it rebuilt? Im a little worried this shock has always had a problem since day 1 when I got the frame. New - old stock
blown damper. It will need rebuilding and possibly new parts like shims. Send it to suspension werx or vorsprung


Or, since you're in Ontario, send it to S4 in Quebec. Generally cheaper than both suspension werx or vorsprung, and cheaper/quicker shipping too.

Posted: Jan 24, 2020 at 8:06 Quote
freerider11 wrote:
spaceofades wrote:
Thepureface wrote:
guys I have a cove hooker bike and there is a problem with it.

The rear shock is a fox rp23.

The problem is that it just blows through travel and the pedal assist doesnt seem to work.

Anyways do you think I could change the rear shock to something that is firmer? Maybe something like the monarch shock that has different tunes?

I also have a pslope and it has a monarch with an mm tune. It also has a very different rear suspension I know.

How to know what tune, and what size shock would fit?


Or is the fox rp23 an okay shock and maybe just get it rebuilt? Im a little worried this shock has always had a problem since day 1 when I got the frame. New - old stock
blown damper. It will need rebuilding and possibly new parts like shims. Send it to suspension werx or vorsprung


Or, since you're in Ontario, send it to S4 in Quebec. Generally cheaper than both suspension werx or vorsprung, and cheaper/quicker shipping too.

Posted: Jan 24, 2020 at 9:38 Quote
Wow that was an easy diagnosis- while on the topic. What causes a blown damper?

Thanks guys.

Posted: Jan 24, 2020 at 10:59 Quote
Thepureface wrote:
Wow that was an easy diagnosis- while on the topic. What causes a blown damper?

Thanks guys.

Wear and tear man! Seals wear parts brake shit like that

Posted: Jan 24, 2020 at 17:17 Quote
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.

Posted: Jan 24, 2020 at 18:41 Quote
Or check out the homemade parts thread also.

Posted: Jan 24, 2020 at 22:13 Quote
Hi is my brake dead?

Sram guide rs 2017, ridden thrice! was fine before bleed!

Front brake bled ok.

Rear brakes after bleeding the lever would go all the way to the bar. Tried again Still lever to the bar. Third time confirms there is not a single bubble in the line.

The only thing I can think of is the rear brakes were disconnected and reconnected as I removed from internal routing. But before the bleed I had brakes now there is very little action at the calipers, does move though.

This is the bleed procedure I did on both brakes.

1. attach hose with prefilled dot 5.1 fluid from automobile shop.
2. pull on syringe let go, repeat until no bubbles
3. attach 2nd hose with prefilled.
4. pull on syringe let go, repeat till no bubbles
5. push fluid from one end to other, repeat, until no bubbles.
6. pull let go few times on both ends
7. pressurize line before disconnecting.

yes once i did check what happened when i pulled lever when syringes were connected - nothing. no pressure on the syringe or calipers.

Madder

i have about 12 shimano brakes from XT, to cheap stuff and they all bleed and work just fine. this is my only sram brake and i've broken it from bleeding it.


 
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