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Steve
01-30-2013, 06:21 AM
On this morning's commute, I noticed that my front brake was staying closed after I released the lever. Not all the way, but enough that the pad was still contacting the rim. When I got to work I checked it out and it just looks like the brake isn't opening back up totally. I am curious if folks think this is due to the cables needing to be lubed or the brake needing to be cleaned? My fear is its a problem with the spring in the brake not being able to open it back up?

As an aside, to lube my cables, I believe that I just drop a little bit of lube where the cable starts (like in the brake lever housing). Is this correct? Is there specific lube for cables, or would something like ProLink chain lube work?

Thanks for any advice!

Dickie
01-30-2013, 06:59 AM
Hey Steve.

Are you brakes caliper or cantilever style? Whenever I have had a sticking brake pad it has almost always been with cantilever brakes. Last week I had a similar issue as you described. When I took a close look I noticed my pads had worn enough that they were not hitting the rim in the same spot anymore, causing the pad to ever so slightly bind/grab the rim, almost as if the pad was getting pinched between the rim and the tire. A quick adjustment of the pad and it worked fine again. When the pad sticks,does it take just a small amount of pressure to release it, and does the spring then work as normal? If so, the spring is not the problem. In terms of lube I always use Tri-Flow, and I apply it as you mentioned. I also use it on the springs and pivot points on the brakes themselves. Hope that helps.

Steve
01-30-2013, 07:18 AM
Hey Steve.

Are you brakes caliper or cantilever style? Whenever I have had a sticking brake pad it has almost always been with cantilever brakes. Last week I had a similar issue as you described. When I took a close look I noticed my pads had worn enough that they were not hitting the rim in the same spot anymore, causing the pad to ever so slightly bind/grab the rim, almost as if the pad was getting pinched between the rim and the tire. A quick adjustment of the pad and it worked fine again. When the pad sticks,does it take just a small amount of pressure to release it, and does the spring then work as normal? If so, the spring is not the problem. In terms of lube I always use Tri-Flow, and I apply it as you mentioned. I also use it on the springs and pivot points on the brakes themselves. Hope that helps.


Thanks, Dickie. Mine are caliper. I think they are contacting the rim ok. The problem exists even when I'm not moving, so I don't think it is the pad just sticking to the rim. It seems more like the whole brake isn't opening back up. I just have to pull the brake open lightly to get it to open back up, like it's just stuck a little bit. Perhaps tonight I'll try cleaning the brake well and lubing the pivot points. My guess is all the rain in the last few weeks has created some friction (I don't have covered bike parking at work, so it gets wet).

Dickie
01-30-2013, 07:35 AM
It could be any number of things. If the bike sits in the rain the cables might have rusted causing them to bind or grab the casing. You can release the cable at the brake end and see if you feel any resistance when you pull on the cable from the lever side (don't pull the cable too far through however as you don't want to have any frayed ends disappear into the housing). If you feel something grab, or it is has unusual resistance check to see if you have any kinks in the cable, if so, try straightening them out an then apply some lube. If you feel no grabbing or resistance then the brake itself is sticking. You can also check this easily now the brake cable has been released by manually closing the brakes against the rim and seeing if you feel any kinks or resistance, again when you release as well. More likely than not your guess is correct.... road gunk, dirt, and lack of lube on the pivot points and spring contacts is most likely causing the problem. Nice thing about brakes is that problem solving is relatively easy and simply a process of elimination. best of luck.

Dirt
01-30-2013, 08:25 AM
Like Dickie says, it could be a few different things. Some brakes (early SRAM and some Tektro dual pivot models) have this as a chronic issue. I found that if I removed the caliper from the bike, removed the brake pad and sprayed it out with Clean Streak or some similar kind of solvent, it helped. Before re-installing, I put a few drops of tri-flow on the pivot points... making sure to clean all residue off before re-installing. Replacing the cable and cable housing is a good idea too.

Hope that helps.

Pete

GuyContinental
01-30-2013, 08:34 AM
Good advice from Dickie but if you haven't done it in a while I'd strongly consider replacing the whole cable and housing, just lube probably won't do the trick if the housing is full of gunk and the cable is corroded. Just buy bulk cable and housing from your LBS- $6-7 (although proper cable cutters are worth it IMO and will cost another $15-$20).

I replace the cable & housing on my high mileage bikes every year- the crazy OCD pink folk amongst us do it like every 6-months.

vvill
01-30-2013, 08:39 AM
I would oil/lube the pivot points first.

Dirt
01-30-2013, 08:54 AM
I would oil/lube the pivot points first.
Depending on what kind of brake it is, just lubing the pivots may make it work for a few days, then you're right back where you started. That's what both the first generation SRAM dual pivot and the Tektro dual pivot caliper brakes did for me on many occasions. Water, brake dust and road grime that gets into the pivots needs to be cleaned out to really solve the problem.

vvill
01-30-2013, 09:23 AM
But that requires time/effort :(

Seriously though yes, I agree. Better to make sure it's working right instead of coming back a few days later and having the same issues again.

Steve
01-30-2013, 10:02 AM
You people are awesome!

Using some of Dickie's advice, I went out and did some trouble shooting. I released the quick release and manually closed the brakes, and they had a similarly hard time re-opening. This leads me to believe that it is not a cable/housing issue, but rather friction at the pivot points themselves.

As correctly guessed by Pete, these are Tektro dual-pivot brakes. I'm going to try to clean the brake well when I get home and lube the pivots and see where that gets me.

I really do appreciate the thoughtful reponses. Huge help.

Steve
01-30-2013, 10:06 AM
One quick follow up question:

Two mentions of Tri-Flow. I have some ProLink chain lube at home. Would this work the same, or are these different types of lubricants?

Thanks.

Dirt
01-30-2013, 10:48 AM
Pro-link and Tri-flow are different.... Pro-link will probably work fine. I haven't compared the two.

vvill
01-30-2013, 01:07 PM
You people are awesome!

Using some of Dickie's advice, I went out and did some trouble shooting. I released the quick release and manually closed the brakes, and they had a similarly hard time re-opening. This leads me to believe that it is not a cable/housing issue, but rather friction at the pivot points themselves.

As correctly guessed by Pete, these are Tektro dual-pivot brakes. I'm going to try to clean the brake well when I get home and lube the pivots and see where that gets me.

I really do appreciate the thoughtful reponses. Huge help.

Sounds good. I have Tektro (R540s? maybe) on my road bike and I had a similar problem awhile ago - squeaking whenever I braked and slight stickiness, so I just put some 3-in-1 oil in there and it seemed to clear up.

Steve
01-30-2013, 04:30 PM
Lube in the contact points seemed to do the trick. I appreciate all the help. Over the weekend I had planned on cleaning my whole bike anyways, so I think I'll follow Pete's advice then and remove the brake and pads for a real cleaning to make sure it's a longer term solution. Again thanks.

thecyclingeconomist
01-30-2013, 04:36 PM
Pro-link and Tri-flow are different.... Pro-link will probably work fine. I haven't compared the two.

Pro-link is a much lighter lubricant, but also repels "Dirt" much better. HA HA!

At brake pivot's, 3-n-one, pro-link, tri-flow, white lightening etc etc... will all work the same at first. It really depends upon how much you ride this steed and in what conditions: wet dirty vs. dry & clean. The heavier the lube, the longer it'll last, but the more dirt it'll pick up.

Just my 2-cents.

GuyContinental
01-31-2013, 07:18 AM
Pro-link and Tri-flow are different.... Pro-link will probably work fine. I haven't compared the two.

Yup- Triflow is a PTFE (Teflon) lube and Pro-link a more traditional solvent/petroleum lube. Others will know way more- key fact, DON'T MIX DIFFERENT TYPES OF LUBE. I use Pro-link for everything and buy in bulk. It is lighter and requires frequent re-application but just works for me, probably because I like lubing my bike. I use the Prolink pen needle thing to get into pivots and cables- kind of a silly $5 to spend but it rounded out a free shipping offer and works better than a nail so meh.