Adjusting bike disc brakes - can't get to inner adjuster

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boland

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#309412 17-Oct-2023 12:57

I've got an e-bike and have always struggled with adjusting the rear disc brakes as I can't reach the inner adjuster, without removing the whole brake caliper. Guess this is caused by the fact the rear wheel has the electrical motor which takes up too much space. See photo below. I've worked around it by taking the brake out, trying to guess how much to adjust, and then trying to put it back in; aligning with other bolts to adjust horizontally. This is a very time consuming process to ensure it doesn't rub AND it has enough tension.

I'm trying to follow this video which seems very easy, if you can reach the inner adjuster. Any tips? Perhaps would work with a flexible allen key if they exist? There's only about 1cm of space.

thewabbit

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#3148404 17-Oct-2023 13:05

Take the wheel off?

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Handsomedan

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#3148416 17-Oct-2023 13:31

The only solution that I can see is to remove the wheel - the problem is that those brakes are clearly designed with a smaller hub in mind (i.e. a standard hub), not the hub-motor unit that you have there.

If I am honest, I haven't seen a set of bike disc brakes that adjust in that way for quite a long time - and on an eBike I'd be pretty reluctant to be using cable-actuated disc brakes too - with the added weight and speeds that they can go, I'd always be going for a hydraulic brake (which can be sourced pretty cheaply and are largely self-adjusting).

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RunningMan

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#3148418 17-Oct-2023 13:37

Ball headed allen key might do it.

wellygary

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#3148425 17-Oct-2023 14:09

Hex Key + Hacksaw the end down might get you a short enough head, -

Batman

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#3148436 17-Oct-2023 15:01

Don't take the wheel off. Without the wheel you have no idea where to place the brake caliper

boland

475 posts

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#3148447 17-Oct-2023 15:16

Handsomedan:

The only solution that I can see is to remove the wheel - the problem is that those brakes are clearly designed with a smaller hub in mind (i.e. a standard hub), not the hub-motor unit that you have there.

If I am honest, I haven't seen a set of bike disc brakes that adjust in that way for quite a long time - and on an eBike I'd be pretty reluctant to be using cable-actuated disc brakes too - with the added weight and speeds that they can go, I'd always be going for a hydraulic brake (which can be sourced pretty cheaply and are largely self-adjusting).

Yeah, I think it's a design issue. Not so keen on taking the wheel out.

Perhaps a good idea to get hydraulic brakes as I use my bike mainly to get up & down a ~150 meter hill, so have to brake a lot going downhill to stay under 50km/hour. I have to adjust them every couple of months as the pads wear down quickly.

Doesn't look very easy to install, so guess I'll leave that to a mechanic.

boland

475 posts

Ultimate Geek

#3148459 17-Oct-2023 15:39

Quick update: Going to drop it off now at a mechanic to get hydraulic brakes installed! Didn't know they were self adjusting, thanks everyone.

Handsomedan

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#3148472 17-Oct-2023 16:28

boland:

Quick update: Going to drop it off now at a mechanic to get hydraulic brakes installed! Didn't know they were self adjusting, thanks everyone.

A wise choice. I have almost zero issues with my hydraulic brakes on my Mountain Bike and it gets a pretty rough life.

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mdf

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#3148481 17-Oct-2023 16:44

I think it is a moot point now, but you can get stubby allen wrenches. I had a set from a cycle shop, so would guess that your problem wasn't unique.

Oblivian

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#3148482 17-Oct-2023 16:56

At a hazzard of a guess that plate should only maybe come off to replace the pads. Not adjust.

The barrel adjustment on the entry point should normally takes care of wear slack and cable stretch. Bringing in the calipers.

Unlike Normal hydro sets that have easy access drop in slot. However looks like noth have a separator pin in the middle to push them out away from rotor.

Do note you'll need to take more care with mineral oil bleeding and keeping the pistons clean with a hydro set.