New wheels rotors and pads, did the hold the brakes and tighten caliper bolts little by little alternating. Managed to get the back wheel not rubbing but front wheel rotor rubs in the same spot once per revolution.
These rotors weren't cheap (Swissstop) but as I understand they might not be perfectly true from that factory?
Before I buy a truing tool or take a crescent wrench to them and potentially make it worse, since I've never done that before, should I crack the top bleed screw and try to push the Pistons in even farther? They were recently bled by LBS who installed new pads a couple months ago on old rotors.
It's just rubbing by a hair. The pistons body go back into the caliper flush but the teeth on the pistons seem to protrude into the caliper by a hair or so, it's hard to tell. I was never able to adjust it so I could physically see a gap on both sides of the pads after 3 hours of trying all the YouTube methods.
by tolem
10 Comments
This may or may not work in your situation, but I always slide a business card between the pads and rotor on both sides before tightening the brake mount down.
I use these or something like it that I got for $5 and it works great:
https://preview.redd.it/bt96w5ph9lye1.jpeg?width=1179&format=pjpg&auto=webp&s=8a79ed62eee72cfe3914c5c9c5b2f63a81fdf2f0
Yes, you should try to push the pistons in all the way, to start from a reset position. You should always open the top bleed port when forcing the pistons into the caliper, just in case there is too much fluid (and thus too much pressure) in the system. Not doing so can permanently damage the master cylinder at the lever, and/or the caliper.
When truing the rotor, the key is to use a light touch. If the rotor won’t bend, you can gradually use a little more pressure until it does.
I’d just ride it and after the first ride the rubbing is usually gone.
Simplist thing to do would be loosen the bolts that clamp the caliper to the frame slightly and apply the brake and tightening the bolts before releasing. Its not foolproof but it often helps centre things again after a new rotor is fitted. Other than that its not unheard of for rotors to not be perfect.
Looks like the rotor is rubbing your caliper. Pull off the rotor and slide 2 washers between it and the frame on each bolt. You should have enough clearance in the rotor.
I just eyeball it, the squeeze and tighten has never worked for me.
Undo one end, shuffle caliper over etc. until no rubbing. However if it’s one spot, tweak the rotor.
I had a similar issue where the outer diameter of the rotor was rubbing into the caliper, like it was just ever too big. I put a couple small washers unter the caliper bolts to space it out and fixed the issue.
Is there rubbing because you cant push the piston back in far enough or because the rotor is wobbling?
Not sure what pads you use but some afermarket brake pads are thicker so you might struggle to get the pistons in far enough. Depending on how the brakes were bled you might have too much oil in the brakes
If the disc is not true you can straighen it a bit with an adjustable wrench.
Usually I just make sure the rotor is centered and parallel in the caliper. The calipers and pads will figure out the rubbing after a bit of riding.
Also as a mtb person I tolerate some brake rub.
It looks to me like the rotor is rubbing on the calliper, in diameter not width if that’s makes sense.
Probably an imperial disk on a metric mount. Just slip a washer under the caliper body