Rear sprocket and brake questions

[seven]

I changed my brake pads a few weeks ago from stock to EBC HH pads. I only had a couple rides on them before replacing the rear sprocket. As I have finally been riding more I have noticed noise from the rear under light pressure on the rear brake like when just coming to a stop. I thought maybe my wheel wasn't properly aligned but I think I have it pretty good. I don't feel anything like pulsing that I have felt in cars when you get pad material deposits. It is just noise. I checked the rotor and I do not see deposits.

When I was checking my wheel alignment I saw some movement in the sprocket. Both linked videos are of the bike up on a swing arm stand and idling in first gear. For the brake video I am applying some mild pressure on the brake pedal. Of note, when actually riding and braking it seems like the noise is more frequent where in the video it sounds like it might be on just each rotation. I have not been able to confirm any of that though.

Is this movement in the sprocket normal? I was cognizant of making sure everything was good and clean during assembly. I also watched the wheel during rotation and I don't see the same movement.

Sprocket movement

Brake noise

I did not use and brake lube like I do on car brakes but I never saw anything about needing to do that on a bike. I also didn't regrease any of the pins as I thought they would be fine with what they had.

Bike had 3500km on OE parts before replacing. 

[Pursuvant]

Just getting fundamentals outta the way, did you bed the HH pads after install? I've noticed front can make some extra noise untill I put those new EBC babies to bed - just noise nada else

[seven]

1 hour ago, Pursuvant said:

Just getting fundamentals outta the way, did you bed the HH pads after install? I've noticed front can make some extra noise untill I put those new EBC babies to bed - just noise nada else

I did do a bed in session and coincidentally I actually went out for a ride right after posting and also thought to try another bedding session. It was raining so more an exercise in ABS engagement but I think the brake got hot enough. Will see if it helps any on my next ride.

[M. Hausknecht]

Did you deglaze the discs to remove the original brake pad material? I have never not done it, so personally I have no experience with the symptoms when incompatible pad material attempts to co-exist on the same disc, but it could be your problem.

[Pursuvant]

1 hour ago, M. Hausknecht said:

Did you deglaze the discs to remove the original brake pad material?

That's a good point (not trying to hi-jack OP thread) - I started using those "scotchbrite scrub pads" on discs every time new pads go in, I like to think it's making a difference

Edited May 3, 2021 by Pursuvant

[M. Hausknecht]

OP noted noise when applying rear brake lightly. Noise is vibration, right? I dunno what his problem is but I don't think its sprocket related.

[seven]

22 hours ago, M. Hausknecht said:

Did you deglaze the discs to remove the original brake pad material?

No I didn't. My understanding was that it was not really needed and doing the bed in process would basically take care of that.

21 hours ago, M. Hausknecht said:

OP noted noise when applying rear brake lightly. Noise is vibration, right? I dunno what his problem is but I don't think its sprocket related.

And from what I can tell the brake rotor seems to be moving in a nice flat plane and I do not feel pulsing. I am thinking of grabbing a dial gauge to see if in fact everything is rotating properly.

Further update, after doing another bedding session the problem persists. Is it possible to deglaze the rotor now and start again? Would I also need to clean up the pad surface too? If so what is the best course of action for both? Interestingly I do not get any noise from the fronts which were installed the same way.

Regarding the sprocket, even if it is not the problem with the brake, is that normal movement that I see in my video?

[shinyribs]

Are you just hearing a slight hissing noise? Like a "ssssssss" sound, similar to a couple pieces of paper siding against each other? If so, you're just noticing the normal sound they make when creating friction. The HH pads are a bit louder than stock. More friction, more sound. 

 

Your sprocket looks fine. The whole rear sprocket assembly is rubber mounted and not rigidly fixed like a wheel is. It'll float some. Also, sprockets are not produced/machined like a gear or brake rotor is, so they very often have a certain degree of runout of their own. Combined with their rubber mounting, they can look pretty wobbly compared to a rim or brake rotor. Chains are flexy, so they don't mind. I don't believe you have anything to worry about! 

 

Edit: the brake video finally loaded. That chatter is the pads vibrating a bit. Double check all your spring plates are properly installed. They can be a bugger and slip out of place easily when you have things apart. 

 

If you decide you need to "deglaze" your rotors, and don't want to get too aggressive with it, there are things made specifically for that. Bardahl is my favorite. They simply call it anti brake squeal. A few drops on the pad faces and they'll settle into their new home immediately without any weird ceremonies involving heat cycles, panic stops or whatever techniques are being done now. I live on a gravel road and that dust permeates everything. My pads will squeal when they start getting funky. A little Bardahl sorts it in out in a hurry. 

Edited May 4, 2021 by shinyribs

[FZWes]

"Weird ceremonies" LOL! Good one.

 

[Pursuvant]

There was this, apparently the service manual had less than optimum torque specs for rear wheel sprocket nuts. 

 

Published sprocket nut torque too hot

[seven]

10 hours ago, shinyribs said:

Are you just hearing a slight hissing noise? Like a "ssssssss" sound, similar to a couple pieces of paper siding against each other? If so, you're just noticing the normal sound they make when creating friction. The HH pads are a bit louder than stock. More friction, more sound. 

 

Your sprocket looks fine. The whole rear sprocket assembly is rubber mounted and not rigidly fixed like a wheel is. It'll float some. Also, sprockets are not produced/machined like a gear or brake rotor is, so they very often have a certain degree of runout of their own. Combined with their rubber mounting, they can look pretty wobbly compared to a rim or brake rotor. Chains are flexy, so they don't mind. I don't believe you have anything to worry about! 

 

Edit: the brake video finally loaded. That chatter is the pads vibrating a bit. Double check all your spring plates are properly installed. They can be a bugger and slip out of place easily when you have things apart. 

 

If you decide you need to "deglaze" your rotors, and don't want to get too aggressive with it, there are things made specifically for that. Bardahl is my favorite. They simply call it anti brake squeal. A few drops on the pad faces and they'll settle into their new home immediately without any weird ceremonies involving heat cycles, panic stops or whatever techniques are being done now. I live on a gravel road and that dust permeates everything. My pads will squeal when they start getting funky. A little Bardahl sorts it in out in a hurry. 

Glad to hear about the sprocket. I had even noticed that the chain guide on the swing arm deflects the chain a tiny bit so it bows out very slightly. Seeing all of this I thought back to the comments people have made about the loose tolerances of this bike akin to someone building it in their back yard.

I will recheck the pads, regrease the pins and maybe grab some Bardahl. 

The pads themselves don't need "anti-squeal" lube like brake pads on cars do they?

1 hour ago, Pursuvant said:

There was this, apparently the service manual had less than optimum torque specs for rear wheel sprocket nuts. 

 

Published sprocket nut torque too hot

Yeah I was using my shop manual and it has the 80Nm (59 lbs ft). Not the first time a service manual has had incorrect values. Heck in an Audi TT manual we once found 3 different torque specs for a mount in different sections of the book...thank god for helicoils!

Sometimes I think I should just go by feel and not worry too much about torque specs.

[shinyribs]

13 minutes ago, seven said:

Glad to hear about the sprocket. I had even noticed that the chain guide on the swing arm deflects the chain a tiny bit so it bows out very slightly. Seeing all of this I thought back to the comments people have made about the loose tolerances of this bike akin to someone building it in their back yard.

I will recheck the pads, regrease the pins and maybe grab some Bardahl. 

The pads themselves don't need "anti-squeal" lube like brake pads on cars do they?

Yeah I was using my shop manual and it has the 80Nm (59 lbs ft). Not the first time a service manual has had incorrect values. Heck in an Audi TT manual we once found 3 different torque specs for a mount in different sections of the book...thank god for helicoils!

Sometimes I think I should just go by feel and not worry too much about torque specs.

I know what you mean with the wobbly chain guide. My 07 had the most chain nose I ever heard on a bike and I didn't know why. I finally noticed that "bent" chain guide. I took a razor and shaved the center rib off. It stopped it from "derailing" the chain and the weird noise went away. I was gonna replace it, but it's still going strong ( without the rib) 20,000+ miles later. That's the only thing on the bike I've thought was cheesy. Otherwise, everything is tight and solid IMO. And my bike's been through some stuff. 

I've never used anti squeal lube on pads, so I can't speak to that. 

And yeah...torque wrenches. I'm pretty sure 90% of all snapped bolts and stripped holes I've seen have been the result of torque wrenches. They've been known to lie!

[seven]

Okay, maybe I did something stupid so someone that has replaced their stock pads with the EBC HH pads please chime in.

Did I need to reuse the rear shim and isolating pads from the stock brake pads on EBC HH pads?

Re-reading the service manual I see the front pads and shim plate show as a single grouped part. And I do remember the EBC pads had a shim installed although it was perforated unlike the stock pad that had a solid shim.

However I do not remember if the rear EBC pads had a shim and insulator installed but I don't think they did and pictures on the internet do not show any installed. In the service manual the stock pads, shims and isolator pads are each separate items. So did I mess that part up?

[Curious kid]

Bike just passed 8k miles.. Is my rear sprocket still ok?