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Kano
09-13-2009, 08:21 PM
First question --

My road bike has "stock" brake pads -- whatever the LBS installs when they build the bikes, y'know? So I'm wondering if there's diferences in brake pads and I'd get more grip from some other brake pad? These work well enough, I'm sure, for the most part, and I'm probably being a bit silly, but I'd love to feel like they're doing a bit more to slow me down on a serious downhill run. Currently, if I'm on a downhill where I want to slow myself, my poor hands/forearms!

Maybe that's the way of things, but if it doesn't have to be, that would be so cool!

Now, Second question:

My old Trek hybrid has "traditional cantilever brakes." I don't know anything about the quality of them, just that I'm wondering if there's something else I could be installing instead. WAY too often, these buggers need to be adjusted because they're off center and rubbing on the wheels. If the "rules" are "once cantilever always cantilever" then what can I do to make this brake more reliable? I do want to be able to stop, but I also want to be able to GO!

Karen in Boise

Becky
09-14-2009, 04:32 AM
IME, it depends a little bit on what the stock brakes are. The pads come with the brakes that come with the bike, so the LBS just assembles what's in the box. I've had very good luck with Shimano Ultegra pads and with Kool-Stop pads. I'd ask your LBS what they recommend for your area.

As for cantis, the ones on my old hybrid were horrible- always rubbing. But the wheels were also pretty terrible- never quite true. So it was a case of the chicken and the egg. The Avid Shorty 6s on my commuter have worked great and rarely go out of alignment, but that bike has better wheels too. It's hard to say what the root cause of the hybrid's brake issues was. I would double-check that your wheels are true and the brakes are set up properly (pads aligned and tight, spring tension, etc.). If that doesn't fix it, maybe it's time for better cantis. I've had good luck with my Avids (though not everyone likes them). The Tektro CR720s get great reviews and are pretty affordable IIRC.

DebW
09-14-2009, 06:01 AM
First question --

My road bike has "stock" brake pads -- whatever the LBS installs when they build the bikes, y'know? So I'm wondering if there's diferences in brake pads and I'd get more grip from some other brake pad? These work well enough, I'm sure, for the most part, and I'm probably being a bit silly, but I'd love to feel like they're doing a bit more to slow me down on a serious downhill run. Currently, if I'm on a downhill where I want to slow myself, my poor hands/forearms!

The pads come with the brakes. There are differences in pad compound, some better for wet conditions, some better for dry. There are also big differences in brake quality. Cheap brakes have too much flex in the calipers and don't stop as well. You may find that upgrading the pads doesn't do much but upgrading the whole brake would make a huge difference, depending on what brakes came with the bike.


Now, Second question:

My old Trek hybrid has "traditional cantilever brakes." I don't know anything about the quality of them, just that I'm wondering if there's something else I could be installing instead. WAY too often, these buggers need to be adjusted because they're off center and rubbing on the wheels. If the "rules" are "once cantilever always cantilever" then what can I do to make this brake more reliable? I do want to be able to stop, but I also want to be able to GO!

The canti brakes on most hybrids are fairly low quality. The brakes have a spring on each arm to help center the brakes, but since each arm has an independent spring, the arms don't really work together well. Sometimes those springs do almost nothing, and it's quite common for the plastic sleeve around the spring to break. You can also adjust the centering on canti brakes by moving the pads in and out on their rods that attach them to the arms. And note that the length of the bridge cable can affect the function of the brakes. Cantis really can be a PITA to adjust properly, and sometimes the cheap ones just can't be well-centered. I'd first check if the plastic sleeves around the springs are broken and if the length of post exposed on the pad connectors is even or not. If that looks OK, try adjusting spring tension with the screws on one or both side of the brakes.

pinkbikes
11-14-2009, 12:44 AM
This seems like a good place to ask this question...

Ever since I have had mountain bikes with hydraulic disks I have considered my roadie brakes pretty awful. Not sure how I ever used to think they were ok actually!:o

Currently I am riding 105 brakes on a standard Shimano R500 wheel. The original equipment brake pads were pretty miserable, so DH got a bunch of aftermarket pads for both his bikes and mine and they seemed a little better.

After a few wet rides at events (so no real choice but to keep riding) I have noticed that they are not as good as they were, and indeed when I rode for the first time in a week the other day, I actually overshot the stopping bar at the bottom of our hill! Luckily nothing was coming the other way.:eek: And they did feel better as the ride went on.

Then today I was doing our local "epic climb" and on the resulting decent I was a bit cautious about letting the bike run because the end of the descent stops at a stop sign! The brakes were pretty ordinary I thought, and sounded maybe a bit scratchy (?) to me?

I am wondering whether the braking surface of the rims needs to be cleaned up? They look like there is black stuff in streaks on them. Or whether the pads are a bit glazed (like disk pads can) from all the muck they may have picked up in the wet rides? Do I need new pads or should I be giving them a light roughening with some emery paper?:confused:

Can anybody recommend good pads for 105 brakes? I'd like to think that they are not the cheapest brakes around and could be decent with the right pads?:)

DebW
11-14-2009, 05:45 PM
Definitely clean the rims and pad surfaces. Alcohol on the rims, emery paper or a metal file on the pads. Glazing does make your brakes less effective.

pinkbikes
11-15-2009, 12:16 PM
Thanks DebW.:)

lph
11-15-2009, 01:44 PM
and if they sound scratchy they probably are - you probaly have a little road gunk embedded in the rubber. File them a little until they look fresh and black and rubbery!

radicalrye
12-12-2009, 06:35 PM
I def. second the filing. Even if you just get some fine grain sand paper it works. I suggest filling the pads themselves and the rims for sure.

I'm pretty sure if you have canti mounts you could also switch to V brakes. Those seem to be pretty reliable and they don't need as much adjusting. I just got my first bike with canti's and I've had to adjust them a couple times. Depending on how old the bike is you may want to replace the brake cables. They can stretch over time.

DebW
12-13-2009, 07:24 AM
I def. second the filing. Even if you just get some fine grain sand paper it works. I suggest filling the pads themselves and the rims for sure.

I'm pretty sure if you have canti mounts you could also switch to V brakes. Those seem to be pretty reliable and they don't need as much adjusting. I just got my first bike with canti's and I've had to adjust them a couple times. Depending on how old the bike is you may want to replace the brake cables. They can stretch over time.

If you switch from cantis to V-brakes, you need different levers. V-brakes pull less cable. Cantis and caliper road brakes can use the same levers, but not V-brakes.

lunacycles
12-14-2009, 03:55 PM
Mini V's work with standard brake levers, quite well. Tektro makes some good ones.

They are actually a very decent alternative to canti's (some would say superior to canti's) on bikes with brifters.

tulip
08-27-2010, 12:47 PM
BUMP...

I installed new brake pads on my Luna today. I replaced the old ones because they were five years old and I could hardly see them anymore. I replaced them with Shimano Dura-Ace/Ultegra pads (same pads as the old ones).

My question is this: Now that I have them on the bike, I managed to get the front wheel back on, but the brakes are tight against the rim. I opened the brake release all the way before removing the wheel the first time, so that's not the issue.

I cannot get my rear wheel back on because the brake pads are too tight. The release is fully open. I even deflated the rear tire. I played around with the cable adjusters but the brakes are still too tight. It's like the new brake pads just add too much material, not allowing enough space for the rim. As I said, my old brakes were down to just about nothing.

I've looked up Sheldon Brown and I've referred to my bicycle repair book. My brakes are Ultegra. There is no bolt on the front of the brake arms to adjust. That seems to be my problem.

Can anyone provide some direction to me on how to widen the brake arms? Thanks so much.

lph
08-27-2010, 02:12 PM
Loosen the point where the cable attaches to the brake and give the cable a little more slack. I usually squeeze the brake pads to the rim with one hand and pull the cable tight, then back the cable off a little (5 mm?) before I tighten the cable bolt again. Then centre the brake pads. If they rub or are too close, open the bolt and let out a little more cable.

lunacycles
08-27-2010, 04:11 PM
What LPH said, Ms. Tulip...you need to create more cable slack to accommodate the new brake pads.

tulip
08-29-2010, 09:53 AM
LPH and Margo-that's just what I did; it just took me a while of looking at it to figure it out. The work great-no squealing! I also put new tires on (Seca Serfas red stripe-very sharp) and cleaned the drivetrain. Next up is new bar tape and eventually new cables but for now, the cables are fine. I took it out for a spirited 40-mile ride yesterday and it performed flawlessly. Love that Luna!

smilingcat
09-04-2010, 08:45 PM
My SRAM FORCE brake pads are worn and need replacing. Bought a pair of new brake pads BUT...

I can't get the old pads to slide out or pop out of the metal shell. Yes I did remove the screw on the shell and the pads should slide out but its not. :mad::mad::mad:

Looks like the metal shell on the SRAM brakes are crimped in on the back side and not allowing the pad to slide out. oui!!!

The pads are worn and I just want to replace. It still has good braking so much so that I managed to pop a reverse wheelie with it about 2 weeks ago. Still I should replace. Last thing I need is a worn brake pads to fade on a steep long descents.

I just don't have the finger strength to pop out the old shoe. Time to say "Pretty Please at my LBS" I hate it when I can't take care of things my self!!

GRRR!!!