Your go-to method of centreing a brake calliper

[c3024446]

What’s everyone’s go-to method of centreing a brake calliper on a disc? It takes me way too long to do it just by sight, but this seems to work better than squeezing the lever then tightening the calliper bolts evenly.

Is there a fast, fool-proof way that works - especially on elixir callipers with the pivoting washers that seem to make the calliper pivot as I tighten the bolt :frusty:

 

[pink poodle]

Shimano and hope brakes....

Loosen bolts. Compress lever a few times, spin the wheel a little. Lock the brake and tighten bolts. Release lever and test. If not centred I micro adjust by eye. To do this I only loosen the bolts enough to move calipers one end at a time.

Elixir are a pain. I used a similar approach to above, always keeping the caliper under pressure while tightening.

 

[ozzybmx]

Set the caliper in the centre of the disc, then use a small flat blade screwdriver to push the dominant piston back while the other comes out, this should put them at the same distance out and have everything aligned. Then you can make a small adjustment by loosening the caliper bolts, I line it up by looking down at the gap between the pad and disc to make sure there is nothing rubbing.

 

[Elbo]

I do the same as the poodle. Depending on the quality of the paint job on the bike, the caliper will want to move one way as you tighten the bolts. I find it helps to tighten both bolts evenly, going back and forward between the two. Also, pretty obvious but make sure your wheel is straight in the dropouts before adjusting your caliper position.

 

[moorey]

Always by eye only.

 

[jellylegs]

I just almost tighten them, ride a few meters and apply brakes. When stopped I keep that pressure on the leaver and jump off and tighten fully. Bit hard to explain but works a treat.

 

[link1896]

Do bolts up slowly, alternating between bolts with a 1/4 turn each. Cone and cup mounting hardware is bullshit. If calliper moves when you pull lever, you have a lazy piston, avid/sram are notorious for lazy Pistons

 

[teK--]

Here is my super pedantic method;

1. Spin wheel then slam on brake lever and hold firmly then tighten bolts partially.

2. Check evenness of pads by shining a flood light through caliper from other side so the pad/rotor gap is visible. if during the day then sunlight works even better.

3. Squeeze lever progressively and ensure pads touch rotor at the same time, from both sides and at each end of each pad. The rotor must not be deflected to one side by the brakes otherwise it means your caliper is misaligned or you have a lazy piston.

4. Check step 3 at various points of the rotor circumference, and true the rotor if excess runout.

5. If need to adjust caliper alignment then loosen one bolt slightly and realign caliper by hand using light as a guide. If there is a lazy piston then remove pads and extend pistons then clean all around them with alcohol and a toothbrush then start at step 1 again.

6. once happy with alignment hold brake lever on hard then tighten caliper bolts whilst alternating between each one, but no more than maybe a 1/8 turn at a time to prevent inadvertent movement. don't need to crank them down too hard or you can strip the threads; spec usually about 5Nm.

This method takes longer but I have never had issues with brake noise (except sometimes when wet), or uneven pad wear. Must also ensure rotor bolts are tightened progressively in a star pattern to an even torque.

if you can, get rid of the avid CPS mounting hardware it makes the job that much harder for no perceived benefit.

 

[Jesterarts]

Piece of thin paper card (literally used a birthday card once) on either side of disc, undo caliber bolts, apply brake, tighten caliper bolts, remove card.

Usually gets me sorted. From there and final fine tuning is done by eye loosening a caliper bolt at a time.

 

[The Duckmeister]

Another one for just sighting the gap each side. Chucking a pale-coloured cloth or sheet of paper on the floor under the bike helps give a clearer sight line through the caliper.

Something to watch for, particularly with cheaper brakes is squashed tabs from overtightening; if a dimple has formed around the hole, as you tighten the bolts they'll push the caliper around to where they want it to sit, not where you want it to sit.

 

[pink poodle]

2. Check evenness of pads by shining a flood light through caliper from other side so the pad/rotor gap is visible. if during the day then sunlight works even better.

I only have a small pen light, will this be powerful enough?

 

[teK--]

I only have a small pen light, will this be powerful enough?

It will work but just be more difficult since you need a big beam of light in order to get through to both sides of the rotor with all the bike frame etc in the way. If you have a bigger torch it will be easier.

 

[beezlbub]

Just like teK

I must be pedantic too, teK pretty much just explained exactly how I do this.

 

[trickbooter]

+1 for Tek.

Also, it is worth the time. When you get it right you'll know, brakes feel very different when correctly aligned.

I use a thin flat screwdriver behind the retaining tab of the pads to hold back an out of line opposing piston. Say the right piston is too extended. Flat blade between the left side of the caliper and pad (careful not to damaged the Pistons), push the right back slightly then extend the Pistons again with the brake lever. Keep doing this, switching sides etc until everything is centred. Check with the light.

 

[Ky1e]

I loosen the bolts, cut a business card in half, insert one in either side of the rotor between pad and rotor, then compress brake lever, and tighten bolts evenly. Remove business cards, rotate wheel and a few squeezes on the lever. Has always worked for me..