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Shimano hydraulic disc spacers?

by aartoodeetoo
Sun, Mar 05, 2017 16:29
7

Hi,

I need to get my recently acquired Cube Attain disc bike IN my car (along with a load of other stuff) which means i need to take both wheels off. The bike came with a little orange spacer for the caliper for just this occasion, but i'll need two as i'll need to take both wheels off. I've searched ebay for an extra one, but there are none specifically for my BR RS505 calipers.

Anyone have any idea where i can get another, or will a different (mountain bike?) spacer do the job?

Hope i've explained myself clearly enough!!

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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7 comments

Avatar
iso2000 | 7 years ago
1 like

Put this into Google and you'll find one for £1.99: "Shimano BR-RS505 Pad Spacer - Y8N218000"

Avatar
surly_by_name | 7 years ago
1 like

You don't need to bleed them - as other posters have said, you just need to pry them apart. However, its better to avoid having to do this. You can fashion a pad spacer with an old credit card cut into strips and glued together; if you can't find an old credit card and some superglue, Epic Bleed Solutions will sell you a kit that does the same thing for the princely sum of £4.99.

Avatar
CXR94Di2 | 7 years ago
2 likes

Just place a little bit of wood/card between pads.  Pistons wont come out unless someone repeatedly presses brake lever many times

Avatar
wycombewheeler | 7 years ago
2 likes

mostly an issue when working on the bike, as you may pull the levers inadvertently. But even if you do, you can reset the pistons with a soft plastic tyre lever.

Avatar
aartoodeetoo | 7 years ago
0 likes

Hi,

This is my first disc equipped bike, so i was only following the advice of the bike shop from whom i purchased the bike... The spacer came in the bag of instructions and bits with the bike, and they showed me how to use it. Told me if i take the wheel off and operate the brake lever without a spacer in it then the calipers close up and need bleeding to get the wheel back on.

In the end it doesn't really matter - i've just tried the bike in the car, and it fits just fine with just the front wheel taken off..

Cheers

Avatar
sergius | 7 years ago
0 likes

Erm, 

I've taken the wheels of my bike (Shimano BR-785) numerous times to put it in the car; I've never had to worry about putting spacers in the calipers for travel.

Why do you think this is a necessary step?

Cheers,

Avatar
TypeVertigo replied to sergius | 7 years ago
4 likes

sergius wrote:

Erm, 

I've taken the wheels of my bike (Shimano BR-785) numerous times to put it in the car; I've never had to worry about putting spacers in the calipers for travel.

Why do you think this is a necessary step?

Cheers,

It's because hydraulic disc brakes automatically compensate for pad wear by bringing the pistons ever closer. But, to do this, they make use of the rotor as a basis.

If you were to pull the brake lever on such a brake system with the wheel (and consequently the rotor) removed, the story is that the pistons can come too far out and no longer allow installation of the wheel/rotor.

You can push them back in, via some sort of tool, or you can take due diligence and put in a bleed spacer to keep the pads apart and guard against the pistons coming out with the wheels off. The spacer is there mainly for maintenance purposes. I believe anything will do as a substitute for the bleed spacer, really.

Mechanical disc brake calipers, by contrast, don't have the brake pad wear auto-compensation, so pressing the levers with no wheel/rotor in the caliper is fine. The actuation arm brings the pads back on its own as the cable returns to its starting position.

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