Rear Brake surge

[vamootsman]

After my mechanic changed my tires and shocks, (and told me the rear brake pads would last forever on this thing), The rear brake feels like its grabs then lets go then grabs and lets go like an out of round drum on an old truck that need to be machined down. I took it back and he put new pads in it??????? got it back, have been riding it for 2 weeks, and the surging came back along with a high pitched squeal with each surge. Anything I need to look for when I pull the rear wheel myself and check things out? Anyone ever experience this?

Thanks!

[cnikonpete]

Is it a rhythmic squeak? Put it on the centre stand and get someone to operate the rear brake,and let it go,see if you can pull the brake arm at the wheel any further back,if you can it would suggest that the brake shoes are binding because of a build up of brake dust etc on their pivots.
To be honest though any mechanic would have cleaned and applied heat resistant grease to these when replacing the shoes.
The other possibility is an out of round drum,or maybe something happened when the wheel was removed,did the surging only start after the tyre replacement?

[vamootsman]

Its rhythmic. Opened it up and nothing looks abnormal in the wheel drum. Going to clean it out because he didn't, use some brake on the moving parts, put her back and see what happens.

[vamootsman]

It started after the tyre replacement

[cnikonpete]

Hmm, given that he didn't clean and lube the pivots,I would be a bit suspicious about his care in the correct torque setting being used when the wheel went back.

Hopefully it's just the shoes grabbing,when the shoes are off just make sure the brake lever moves freely,I would remove the adjusting nut so the arm is free from the rod .

[vamootsman]

Hmm, given that he didn't clean and lube the pivots,I would be a bit suspicious about his care in the correct torque setting being used when the wheel went back.

Hopefully it's just the shoes grabbing,when the shoes are off just make sure the brake lever moves freely,I would remove the adjusting nut so the arm is free from the rod .

I cleaned everything and lubed the pivot points with brake lube, put it all back together with the old pads, put a strap on the brake lever to incrementally cinch it down till I could some resistance, and there a distinct spot where the brake grabs harder. Put the new pads back, flipped them for the hell of it, and same result. Put it all back together then checked again, same result.

It's hard to imagine, but could a tyre changing machine bend the wheel or drum? Never used one so don't know.


the squeal is gone for now but I just rode it around the block to make sure all was good and snug, will have to see if I can fell the surging again after work

[gn2]

Sounds to me like either the drum isn't round or the wheel bearings are shot or the wheel and A-bracket haven't been reassembled correctly.
Or a combination of any two or all of the above.

[vamootsman]

Sounds to me like either the drum isn't round or the wheel bearings are shot or the wheel and A-bracket haven't been reassembled correctly.
Or a combination of any two or all of the above.

I could feel the grabbing in the one spot before and after I re-assembled and tightened the A-Frame.

Rode it a bit more, and it's barely perceptible, so will see how it fares after more commuting over the weekend.

[springer1]

Sounds to me like either the drum isn't round

Maybe either not round or has a ding in it. Is there an area on the drum’s surface that has a different color or patina than the rest or can you feel a ding or burr on the surface ?

[vamootsman]

Sounds to me like either the drum isn't round

Maybe either not round or has a ding in it. Is there an area on the drum’s surface that has a different color or patina than the rest or can you feel a ding or burr on the surface ?

I looked it over thoroughly, cleaned it ran my fingers around it and couldn't find anything. I'll ride it for the weekend and if and when it gets worse I'll pull it apart again and put cheaters on, grab a magnifying glass and go at it with some calipers.

Just pissed me off that I got the tyre change, which I needed, but ended up with a can of worms

[cnikonpete]

Is your "mechanic" a tyre fitter or a proper mechanic. If he used an air impact wrench on your bike he could have overloaded the bearing,hope not,but if it persists that might be your next port of call

[vamootsman]

I rode the bike 2 up and alone a little for the last few days, but not too much. Seems to be a lot better after all of my fiddling, but I'm reserving judgment until I can do a proper shake down.

[iceman]

Looking at changing the rear pads on mine as it's done near 16,000 miles and is over 4 years old, and I feel I have used the rear much more the past 2-3 weeks that my front brake lever was hard to press.
There are youtube videos showing rear pad replacement needed on younger PCX so they do wear (there is that check thing in the manual for rear wear). Depends how much and how hard you use the brakes.

[MikeWard]

After my mechanic changed my tires and shocks, (and told me the rear brake pads would last forever on this thing), The rear brake feels like its grabs then lets go then grabs and lets go like an out of round drum on an old truck that need to be machined down. I took it back and he put new pads in it??????? got it back, have been riding it for 2 weeks, and the surging came back along with a high pitched squeal with each surge. Anything I need to look for when I pull the rear wheel myself and check things out? Anyone ever experience this?

Thanks!

I have the exact same issue, but I haven't done any checking because I don't have the tool. Did you find out what the problem was?
I got the same feeling after service at honda dealer shop but was too lae when I noticed...

[vamootsman]

After my mechanic changed my tires and shocks, (and told me the rear brake pads would last forever on this thing), The rear brake feels like its grabs then lets go then grabs and lets go like an out of round drum on an old truck that need to be machined down. I took it back and he put new pads in it??????? got it back, have been riding it for 2 weeks, and the surging came back along with a high pitched squeal with each surge. Anything I need to look for when I pull the rear wheel myself and check things out? Anyone ever experience this?

Thanks!

I have the exact same issue, but I haven't done any checking because I don't have the tool. Did you find out what the problem was?
I got the same feeling after service at honda dealer shop but was too lae when I noticed...

I should have called them shoes, as they are in drum brake.
I put the old shoes back in and the problem went away. They weren't even close to being worn out anyway. Not sure what will happen when I change them next time though. Maybe someone on the forum has recommendation for a better quality set of shoes.