disc brake rubbing from flex?
#1
commu*ist spy
Thread Starter
disc brake rubbing from flex?
I have a 2016 giant tcx, which uses 15f/12r thru axles. I thought this would eliminate rotor rubbing, but I was wrong. when I stand up to put power down on a hill or sprint, the front rotors still rub. it's pretty annoying. curious whether this happens to others.
#4
Junior Member
Join Date: Aug 2017
Posts: 11
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
I have the same issue on my front brakes. In fact, I have aligned the brake multiple times on the stand, and it wont rub. However, once I go out to the road and apply some power and ride, i start getting a local rub every rotation. The rotor must be a bit out of plane but the weird thing is that it doesn't rub when I stop and spin the wheel without load or weight.
#5
Senior Member
Join Date: Dec 2009
Location: Melbourne, Oz
Posts: 9,549
Bikes: https://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=152015&p=1404231
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 1530 Post(s)
Liked 724 Times
in
515 Posts
Oh yeah, road discs are half baked. Had endless hassle trying to eliminate rub in the shop... I don't miss that.
The pad gap is too small. And there's nothing you can do about it on hydraulic systems, as far as I know.
The pad gap is too small. And there's nothing you can do about it on hydraulic systems, as far as I know.
#7
Senior Member
Join Date: Jan 2010
Location: TC, MN
Posts: 39,520
Bikes: R3 Disc, Haanjo
Mentioned: 354 Post(s)
Tagged: 1 Thread(s)
Quoted: 20810 Post(s)
Liked 9,456 Times
in
4,672 Posts
#8
• —
Join Date: Jun 2015
Location: Land of Pleasant Living
Posts: 12,302
Bikes: Shmikes
Mentioned: 59 Post(s)
Tagged: 0 Thread(s)
Quoted: 10212 Post(s)
Liked 5,919 Times
in
3,190 Posts
I've had this too. There's usually a sweet spot/angle, but it can take hours to find. I wish the caliper mounting system were better designed for precise adjustment, perhaps with some visual guides.
#11
commu*ist spy
Thread Starter
all my rotors are 1.5 mm width, they're as true as i can get them. I suspect caliper angle has something to do with it, but there's no way to really change that on the bike. supposedly, the caliper is the one that's at the right angle, and it's the rotor that's slightly angled
what bothers me more is that when I do hard braking down a steep long hill, the rotors rub continuously until it cools off again. this happens on my ice tech rotors as well. I've tried bleeding it and tending to the pistons. hasn't fixed anything
what bothers me more is that when I do hard braking down a steep long hill, the rotors rub continuously until it cools off again. this happens on my ice tech rotors as well. I've tried bleeding it and tending to the pistons. hasn't fixed anything
Last edited by spectastic; 07-30-19 at 09:35 AM.
#12
Senior Member
Join Date: Jul 2006
Posts: 3,095
Mentioned: 63 Post(s)
Tagged: 0 Thread(s)
Quoted: 1237 Post(s)
Liked 192 Times
in
120 Posts
It just happens with some riders. I've yet to ride a road or gravel frame/fork/brake combo I couldn't induce some brake rub on - Until a few weeks ago I worked for the largest bicycle chain retailer in the Southeast so I've ridden a lot of bikes. Some riders just have positions that angle the whole system enough to get brake rub. I mean, even really stiff bikes aren't that stiff. Grab the wheel on any bike and wrench it around and you'll see the rotor/rim move around quite a bit. When you're on the bike, the entire system moves around so many riders never have rub, but many other do. Happens with rim brakes too but most people never noticed because the pad/rim material is quiet.
If it really bothers you try semi-metallic or resin pads, they'll still rub a bit but you won't hear it unless you're in a situation where you're up at 4+ w/kg but going <10 mph.
If it really bothers you try semi-metallic or resin pads, they'll still rub a bit but you won't hear it unless you're in a situation where you're up at 4+ w/kg but going <10 mph.
#13
Senior Member
Join Date: Nov 2015
Posts: 8,922
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 4717 Post(s)
Liked 1,882 Times
in
998 Posts
all my rotors are 1.5 mm width, they're as true as i can get them. I suspect caliper angle has something to do with it, but there's no way to really change that on the bike. supposedly, the caliper is the one that's at the right angle, and it's the rotor that's slightly angled
#14
Senior Member
Join Date: Jan 2010
Location: TC, MN
Posts: 39,520
Bikes: R3 Disc, Haanjo
Mentioned: 354 Post(s)
Tagged: 1 Thread(s)
Quoted: 20810 Post(s)
Liked 9,456 Times
in
4,672 Posts
all my rotors are 1.5 mm width, they're as true as i can get them. I suspect caliper angle has something to do with it, but there's no way to really change that on the bike. supposedly, the caliper is the one that's at the right angle, and it's the rotor that's slightly angled
Also, have you tried the business card trick?
#17
Non omnino gravis
Never had caliper rub ever, on two different bikes, three different forks, two different front rotor sizes, 4 different calipers (everything from basic mechanicals to 4-piston hydraulics,) standard QR axles, and always with rotors much thicker than 1.5mm.
Setting up disc brakes is not difficult. At all. If no amount of tweaking can get it correct, then something is wrong with the fork, caliper, or rotor.
Setting up disc brakes is not difficult. At all. If no amount of tweaking can get it correct, then something is wrong with the fork, caliper, or rotor.
#18
Senior Member
Join Date: Nov 2015
Posts: 8,922
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 4717 Post(s)
Liked 1,882 Times
in
998 Posts
Never had caliper rub ever, on two different bikes, three different forks, two different front rotor sizes, 4 different calipers (everything from basic mechanicals to 4-piston hydraulics,) standard QR axles, and always with rotors much thicker than 1.5mm.
Setting up disc brakes is not difficult. At all. If no amount of tweaking can get it correct, then something is wrong with the fork, caliper, or rotor.
Setting up disc brakes is not difficult. At all. If no amount of tweaking can get it correct, then something is wrong with the fork, caliper, or rotor.
https://www.parktool.com/product/dis...ing-set-dt-5-2
#19
Senior Member
Join Date: Oct 2018
Location: VA
Posts: 1,437
Bikes: SuperSix Evo | Revolt
Mentioned: 12 Post(s)
Tagged: 0 Thread(s)
Quoted: 733 Post(s)
Liked 815 Times
in
414 Posts
This. I thought my front rotor rub was from the rotor heating up, then it was happening the first time I hit the brakes. Checked closer and the outboard piston wasn't fully retracting. It's getting replaced under warranty.
#20
Non omnino gravis
Well, that's pretty much my point. I assume the OP or his shop had fiddled with the setup, and still couldn't get it right. So why hasn't the shop at the very least suggested some corrective measure?
Brakes aren't supposed to rub, and if all parts are mechanically sound and the contact points are straight and clean, there should be no issues. Something on the OPs bike needs to be addressed-- it's not an outright indicator of the fallibility of disc brakes on bicycles.
Brakes aren't supposed to rub, and if all parts are mechanically sound and the contact points are straight and clean, there should be no issues. Something on the OPs bike needs to be addressed-- it's not an outright indicator of the fallibility of disc brakes on bicycles.
Likes For DrIsotope:
#22
commu*ist spy
Thread Starter
however, it still doesn't really explain why there is continuous rubbing after steep down hills. I'm not a fred (165 lbs). The pistons are retracting like they should. I did a bleed job very recently so I doubt there's bubbles in the caliper. not sure what else could be going on
#23
Senior Member
Join Date: Jul 2017
Location: SoCal USA
Posts: 188
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 73 Post(s)
Liked 41 Times
in
33 Posts
ahh I see. but what if I have post mount adapters? there's no real way to shave those very precisely. but I guess if the fork is slightly crooked, it might help. will look into it.
however, it still doesn't really explain why there is continuous rubbing after steep down hills. I'm not a fred (165 lbs). The pistons are retracting like they should. I did a bleed job very recently so I doubt there's bubbles in the caliper. not sure what else could be going on
however, it still doesn't really explain why there is continuous rubbing after steep down hills. I'm not a fred (165 lbs). The pistons are retracting like they should. I did a bleed job very recently so I doubt there's bubbles in the caliper. not sure what else could be going on
Not a deal breaker, but it's noticeable
Likes For RedBullFiXX:
#24
Senior Member
Join Date: Jan 2010
Location: TC, MN
Posts: 39,520
Bikes: R3 Disc, Haanjo
Mentioned: 354 Post(s)
Tagged: 1 Thread(s)
Quoted: 20810 Post(s)
Liked 9,456 Times
in
4,672 Posts
ahh I see. but what if I have post mount adapters? there's no real way to shave those very precisely. but I guess if the fork is slightly crooked, it might help. will look into it.
however, it still doesn't really explain why there is continuous rubbing after steep down hills. I'm not a fred (165 lbs). The pistons are retracting like they should. I did a bleed job very recently so I doubt there's bubbles in the caliper. not sure what else could be going on
however, it still doesn't really explain why there is continuous rubbing after steep down hills. I'm not a fred (165 lbs). The pistons are retracting like they should. I did a bleed job very recently so I doubt there's bubbles in the caliper. not sure what else could be going on
Edit: and the word you're looking for is Clyde, not Fred.
Last edited by WhyFi; 07-30-19 at 04:04 PM.