Improving PCX rear drum brake

[alx123]

In my opinion, the rear brake is the PCX's weakest point.

My complain is the lack of feedback feel, it seems to feel lacking in stopping power but suddenly will lock as soon as you give it a little more squeeze.
The lever feels like it's too loose but once you forced it a little bit will lock the brake before you even feel in the lever that it's already activated.
What I'm looking for is a gradual/progressive brake feel, in which I can easily modulate my braking.
I didn't have this concern on my other bikes before, but mostly are foot brake levers.

Adjusting the lever slack will improve the feel but will also result in the brake shoes engaging a little even when not applied; I can easily tell by rotating the wheel while the scoot is on center stand.

Iv'e tried changing brake shoes, but it only alleviate the problem when it's new and the lack of feedback feel always comeback after a few weeks or so. Iv'e tried other aftermarket brand of brake shoes, and the one I'm using now feels better than the OEM.
I did try to change the spring on the brake arm but it resulted in a very hard lever.

Iv'e posted this problem somewhere before but didn't find any good solution yet.
I'm not sure if it's just me, or this is just how rear drum brakes really feel on hand levers.

[gn2]

Its never going to feel great, that's just how drum brakes are.
The biggest problem is the length of the cable.
Foot brakes feel better because the cable is shorter.
Its the same with cable operated bicycle brakes, the rear usually feels more mushy than the front.

[alx123]

^^^That makes a lot of sense. Do you think CBS contributed to this too?

[fish]

I was unimpressed to learn that the new Piaggio Liberty had a rear drum brake, as well.
Vespa Motorsport's ROBOT passes it off as, "this drum brake will last longer than disc brake pads".
Yeah, well....my KYMCO LIKE200i has twin disc brakes and they provide the best and smoothest braking you can imagine!
And the pads look like they are about 30% worn after 8 summers and 16,000+ miles.
Probably, along with ease of servicing, the LIKE's brakes are my favorite feature of the scooter.
Incredible brakes!

Fish

[gn2]

^^^That makes a lot of sense. Do you think CBS contributed to this too?

Probably will.

[alx123]

I also noticed that Honda's OEM brake shoe is the same for most models; PCX 125, PCX 150, Click 125, Click 150 and even for the 110cc zoomer X. This means this is like a fit-to-all drum brake that doesn't get any updates or improvements. They could've at least gave the 150's a bigger drum for a little better stopping power.

[springer1]

I have no issue with the PCX rear brake and I think the advantages of a disc are nominal anyway on a lightweight low powered scooter. I think the advantages of a disc on a low power light scooter are marketing. I’ve ridden a lot of different motorcycles and scooters over almost 55 years.

[Jge64]

I agree; on a scooter a rear drum brake is fine, we’re not at Daytona. However I believe ABS works the best on a disk brake versus a drum. That’s the only reason I can think of that it’s “better”.

[iceman]

The rear break is not great, front much better but now I would rather not have ABS and stick with the CBS system as it seems perfectly fine, and is much easier and less costly to maintain.

[alx123]

I'm sure a disc brake would feel much better than a drum on the hand lever.
I just changed the shoe on my brakes today as I don't like how spongy the lever feels.

I guess the best thing to do is to just change to a new shoe every time I feel the brakes starting to feel unpredictable.
Sorry to disagree but CBS is just a marketing ploy, it's not functional and doesn't offer any benefits to the rider.
ABS on the other hand is on another level, I believe it should be put on all bikes regardless of displacement.

[gn2]

A longer actuating arm and/or adjustment to the angle the cable meets it at can help.

[Mel46]

You know that everyone has opinions so this may never be resolved, but I think scooters and motorcycles should follow suit with cars. If manufacturers of automobiles have upgraded most cars to rear disc brakes, bikes should follow that lead. Even if...and that is a big IF...drum brakes are fine for scooters, safety would dictate that what works best for other vehicles should work well on a scooter as well.

I feel the brake fade after riding for an extended time on my scooter. I don't believe this is from the front disc brakes (though I could be wrong). To me, disc brakes all around would be safer.

When we had our accident brake fade played a big role. We saw the accident happen in front of us, but our scooter brakes did not slow us enough in time for us to effectively miss it or stop. We had been riding in and out of traffic for 3 hours prior to that so the brake fade was apparent on the rear brake. I know, it will be argued that it wasn't the brake, it was us, but you can actually feel it when brake fade starts. It was mid afternoon, very hot out, and even road temperatures were going up. I could feel it through my boots when we were stopped at a light.

Whatever the arguments for or against rear disc brakes, brake fade is a real issue. If rear disc brakes would help resolve that issue, then I am all for them.

[Inoplanetyanin]

Just came back from a three day loaded touring trip with plenty of steep mountain descends and fast freeway riding ( LA to Pismo Beach and back).

And I had all the confidence in the brakes. They feel great and completely adequate. Never felt the need for anything different.

Advantages of drum brakes is lower wear, dust and dirt protection.

[alx123]

I also believe the brake is adequate enough to stop the small 150 cc engine, I even locked my rear once and skidded. My complain is all about the brake feel.
Iv'e just installed an aftermarket "Bendix" one, and it's great. At least for now.

[Peter Panini]

With a combination of front disc brakes and rear drum brakes, and the correct use of feathering them, I have zero issues with the braking system.

[Inoplanetyanin]

I also believe the brake is adequate enough to stop the small 150 cc engine, I even locked my rear once and skidded. My complain is all about the brake feel.
Iv'e just installed an aftermarket "Bendix" one, and it's great. At least for now.

Sounds like you may have an issue with your brakes or the drum.

I can't imagine mine locking up with normal use.

Have the drum checked for run out and minimum diameter. Also the surface should not be glazed and the drum should not be warped (can happen if it has ever been suddenly cooled after being hot).

Your cables and drum swivel pin should all move freely and be lubricated. I assume there is no corrosion.

Do you live in a climate where there is ocean near by, or do you ride in the rainy weather or let alone in the winter when roads are sprayed with salty acidic solutions?


I imagine brake feel would be very special under conditions like this, for example.



Finally, are any of your parts aftermarket of dubious quality? I've seen that almost anything can be bought or modified in Thailand when it comes to two wheeled transport.

[Limey]

I think the rear brake is fine, too. I locked mine up once so know what pressure is need for that, now!

[Conelite]

Isn't rear braking "feel" poor due to the Combined braking system? You want good brake feel, Eliminate the linked braking system and run a single independent rear brake Cable. Its the only way you will improve the "feel."

[alx123]

^^^That makes a lot of sense. Do you think CBS contributed to this too?

Isn't rear braking "feel" poor due to the Combined braking system? You want good brake feel, Eliminate the linked braking system and run a single independent rear brake Cable. Its the only way you will improve the "feel."

Exactly what I was thinking too. This kind of job is a little complicated for my limited skill, plus I believe you need the strip the scoot for that. I might need my mechanic's help with that.
Newly installed pads improved the braking feel somehow, though in my experience it only last a few weeks or so. We'll see..

[alx123]

I also believe the brake is adequate enough to stop the small 150 cc engine, I even locked my rear once and skidded. My complain is all about the brake feel.
Iv'e just installed an aftermarket "Bendix" one, and it's great. At least for now.

Sounds like you may have an issue with your brakes or the drum. Checked it and it's still within specs

I can't imagine mine locking up with normal use. It was an emergency braking situation, I guess I pressed the brake a little too hard because I don't feel it engaging at first - related to my current complain

Have the drum checked for run out and minimum diameter. Also the surface should not be glazed and the drum should not be warped (can happen if it has ever been suddenly cooled after being hot).

Your cables and drum swivel pin should all move freely and be lubricated. I assume there is no corrosion. - this I need to check, thanks

Do you live in a climate where there is ocean near by, or do you ride in the rainy weather ? - Thailand, so, YES!


Finally, are any of your parts aftermarket of dubious quality? I've seen that almost anything can be bought or modified in Thailand when it comes to two wheeled transport. - No, all OEM except for tires and now usng aftermarket brake shoes(which is better imo)