Tips for Aligning Disc Brake Calipers?

[brewsmith]

I am having a hell of a time getting the rear hydro caliper on my Bingham in the right position. The brakes and pads are new and freshly bled, but no matter what I try I get moderate rubbing on the rear rotor/caliper.
I have tried the usual method of loosening the mounting bolts, pulling the lever and re-tightening and it was was off, I even tried using a shim on the rotor to get some extra room to no avail. Trying to eye the alignment does nothing either. It seems like there is just not enough gap between the pads and the rotor, and I was hoping a few rides bedding the pads etc. would help things settle in but it did not seem to make a difference.

Anyone have a tried and true method or other tips to try? Thanks in advance!

[kppolich]

First thing I check is that I have the rotor installed correctly. I once tried centering a rotor/caliper for 15 minutes only to realize I had the center lock rotor on upside down. DOH

Second item would be to get it centered and firm up one bolt at a time. You can use that first bolt as a rotation point to set the second one and get them perfectly aligned. Just don't cinch down the first bolt so tight that you can't move the second one inboard or outboard to get them centered.

[reuben]

Rim brakes.

Sorry, I realize that's not very helpful, but I'm still trying to recover from threads about crashing on fine sand and crashing through allegedly frozen lakes.

[dddd]

I worked on one like this yesterday, a Cannondale with Ultegra hydraulic brakes.

It required that I apply the brake lever with a rubber band, and with my right hand feeding in through the spokes I applied one finger's worth of modest pressure to the right side of the loose caliper while my left hand tightened the bolts gradually and evenly.
I lucked out and this worked to perfection on the first try, which made me look good in front of the bike's owner.
Previous attempts at self-aligning the caliper all had failed, even after having applied the brake and banged the caliper sideways before tightening the bolts.

Sometimes the short length of hose between the frame or fork and the caliper will bias the sideways position of the caliper, this might have been what I was dealing with(?).

[lavi]

Yes. This certainly frustrating. I had a buddy (Clean39T, shocker) tell me about the Hayes Feel'r alignment tool. It worked.

Else, I just tried to get it work with multiple back to back loosening/tightening.

Seems like a bit of a dark art at times.

Yes, rim brakers...we know. Go for a ride or something.

[Yoshi]

Try spinning the wheel until it rubs. Insert a thin piece of paper on both sides of the disc, then tighten. Has worked for me.

[Black Dog]

I use a rotor shim/pad spacer that you place over the rotor and slide it between the pads on a loosened calliper. Then squeeze the brake and tighten the bolts on the calliper. You can purchase these cheaply on line.

https://www.amazon.ca/Lixada-Adjusti...28572238&psc=1

[fairwent]

Originally Posted by lavi

Yes. This certainly frustrating. I had a buddy (Clean39T, shocker) tell me about the Hayes Feel'r alignment tool. It worked.

Else, I just tried to get it work with multiple back to back loosening/tightening.

Seems like a bit of a dark art at times.

Yes, rim brakers...we know. Go for a ride or something.

This. A very reasonably priced tool to really save time.

[yinzerniner]

Originally Posted by brewsmith

I am having a hell of a time getting the rear hydro caliper on my Bingham in the right position. The brakes and pads are new and freshly bled, but no matter what I try I get moderate rubbing on the rear rotor/caliper.
I have tried the usual method of loosening the mounting bolts, pulling the lever and re-tightening and it was was off, I even tried using a shim on the rotor to get some extra room to no avail. Trying to eye the alignment does nothing either. It seems like there is just not enough gap between the pads and the rotor, and I was hoping a few rides bedding the pads etc. would help things settle in but it did not seem to make a difference.

Anyone have a tried and true method or other tips to try? Thanks in advance!

Two tools, total cost less than $30 and makes alignment of even the most warped rotor a 5 min job.

1- Rotor Truing tool. This one from Bikehand is nice as it also has the piston press.
t.ly/NReN


2- Metal gap indicators. After you press the pistons in put the metal gap thingamajiger on you rotor, then align it with the pads and go about the normal centering process. The metal is just enough of a shim to provide a small gap after centering. I bought these and they're great (even work when in a pinch on a ride).
t.ly/AVNw

[Blown Reek]

All of these "tricks" work just fine if the brake is predisposed to set up correctly. Some disc brakes are nearly impossible to set up correctly, and then that's only on the stand. Once they're in the hands of their, um, capable owners, all bets are off.

However, I realized that the percentage of the cycling population that is actually striving for perfection is really small, and things like rubbing and "tings!" doesn't seem to bother them. Personally, if it ain't perfect, I'm not happy.

Welcome to the world of disc brakes. You'll see that they'll eventually get there, but there's no real formula to it. It's just as much of an art as it is a science.

Rim brakes don't have this issue.

[Peter P.]

Originally Posted by reuben

Rim brakes.

That's funny! And true...

Seriously; is it possible the wheel is not sitting square in the dropouts, or the caliper mount is not machined square to the rotor?

One possibility is it's caused by paint covering the caliper mounting pads. Next would be paint in the dropouts. I'm also inclined to suspect misalignment on forks and rear dropouts, which I would more likely suspect with production frames vs. custom frames.

Really, it shouldn't be that difficult. And if it's that difficult, see reuben's solution above.

[joevers]

I hold the brake down and apply moderate pressure on the pedals while tightening the brake caliper bolts. It's a hell of a juggle to do alone but seems to work extremely well. If you're having trouble a toe strap on the lever helps.

[Gummee]

It could also be that the caliper is moving slightly when you're tightening the bolt.

I've had to add another washer to the bolt to give things less friction.

There have been a few calipers that have fought me. Some take more than a few attempts to get em right. Eventually they do get right.

One of things I do when the first few 'grab the lever and pull when tightening the bolts' doesn't work is eyeball the rotor to caliper clearance and tighten it down while watching the gaps. If you keep an eyeball on the gaps, you can slightly adjust the caliper and eliminate the rubbing

Takes time and patience, but they'll set up without rubbing

M

[mtechnica]

Originally Posted by Gummee

It could also be that the caliper is moving slightly when you're tightening the bolt.

I've had to add another washer to the bolt to give things less friction.

There have been a few calipers that have fought me. Some take more than a few attempts to get em right. Eventually they do get right.

One of things I do when the first few 'grab the lever and pull when tightening the bolts' doesn't work is eyeball the rotor to caliper clearance and tighten it down while watching the gaps. If you keep an eyeball on the gaps, you can slightly adjust the caliper and eliminate the rubbing

Takes time and patience, but they'll set up without rubbing

M

This x100

On some bikes the caliper will move when it's tightened down. You gotta shift it then tighten it then see which side is touching then shift it away and tighten it again.

[joevers]

Also, a surprising amount of bikes of all materials at all price points would brake *substantially* better if the brake mounts were faced. They rarely rarely are.