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jordash
06-30-2012, 11:37 PM
My brakes are Tektro dual-pivots. Recently the brake arms don't want to return to their relaxed position after I let go of the brake lever. I've tried centering and spacing the pads farther back. Once I give the lever a couple squeezes, the brake pads don't retreat, forcing me to disengage the brake so they don't rub the rim.

Has anyone had this problem or know what might cause these new-ish brakes to stick? Could it be spring tension, lack of lube, or could I have broke something when engaging the quick-release?

jcpetrson
07-01-2012, 08:24 AM
Include a picture. I think these are on my Fuji road bike. Sounds like the spring is not set correctly.

My other theory is that your cable is kinked. take it off the brake and see if it slides well. Also, with the cable off, check that the brakes squeeze and return correctly.

off2ride
07-01-2012, 03:05 PM
Disconnect the cable from the caliper and squeeze the caliper by hand to see if releases normally. If that's good, visually check your cable and housing for kinks, corrosion, abnormal stuff. If that's good, operate the brake lever while you're pulling on the end of the cable. It should bottom out easily as you're pulling on the cable end. If there's more give as you're pulling then it's probably housing and cable. So if that's the case, you might as well replace the front too. Good luck.

Dirt
07-01-2012, 05:19 PM
The tektro dual pivots have slightly underpowered springs. It isn't a big deal, but they definitely work much better with new, high-quality brake housing and a slick cable. I've overhauled my old ones a few times and that helps too... the pivots get a little stiff when gunked up a bit. They're a reasonably-priced brake that work well, but don't have the smoothness or durability of the name-brand brakes..

vvill
07-01-2012, 06:30 PM
I have Tektro R580s stock on my road bike. I had some squeaking issues around the pivot at ~1500mi of use, and just used some oil to loosen it up a bit. Seemed to work ok once it penetrated into the pivot.

jordash
07-04-2012, 10:17 AM
Thanks for the responses everybody. I just got power back on yesterday. The bike is only 2 months old and has 1150mi on it, so the cabling quality should be fine. I noticed normal cable wear from the pinch bolt. Once I loosened that and manually clamped the calipers, it's clear there's something wrong with the spring because they do not return outwards. I don't know much about how the spring mechanism works, just that it counter-pressures the two arms.

brendan
07-05-2012, 09:57 AM
Thanks for the responses everybody. I just got power back on yesterday. The bike is only 2 months old and has 1150mi on it, so the cabling quality should be fine. I noticed normal cable wear from the pinch bolt. Once I loosened that and manually clamped the calipers, it's clear there's something wrong with the spring because they do not return outwards. I don't know much about how the spring mechanism works, just that it counter-pressures the two arms.

Are the two spring arms properly seated in the channels in (or against the pins on) the arms? Is the bolt on the vertex properly adjusted? On some brakes it is a tension nut plus lock nut (or lock ring) design, but sometimes the tension bolt gets adjusted too tightly if it was adjusted by someone who wasn't aware of the two adjustments. Also, sometimes that whole bolt could use some de-rusting and greasing.

Brendan

jordash
07-05-2012, 08:16 PM
Thanks Brendan.

When I checked the spring arms' placement in the channels, the arm directly connected to the spring (non-drive side) is fine, meaning it easily returns outward. The brake pad counter-pressured by the spring (non-drive side) gets stuck after I move it inward.

It seems that the spring is fine but something connecting the two arms might have been tweaked while I cloddishly adjusted the quick-release. When re-engaging the brake pads, I did not depress the brake pads onto the rim.

jordash
07-13-2012, 09:15 PM
Seems the problem was minor corrosion of the caliper, probably from a rain ride and the gunk that drips down from the fender. I sprayed some silicone lubricant into the center and all returned to normal.