Caliper looseness

[romulux]

I'm replacing brake lines with stainless and doing other maintenance since I can't ride due to snow.

I noticed that the half of the caliper closest to the left-hand side of the bike rattles like it's a little loose.  Should there be any play on that?  I think it's the solid part right under the number 3 in this picture.




Also, one other thing.

The rear has what appears to be a rubber hose going from the reservoir to another fitting which then connects to the actual rear brake line.  Obviously, I'm more concerned with the front lines, but won't that rubber section diminish the effect of the stainless line on the rear?  I understand I'm not likely to notice it on the rear since you'll lock the rear tire easily regardless, it just seems kind of pointless to have stainless rear line if half the length is rubber.

[the mole]

The "other fitting" on the rear brake is the master cylinder. Your new brake line goes from there to the rear caliper. The other rubber hose supplies fluid to the master cylinder from the reservoir and is not under pressure.

[romulux]

The "other fitting" on the rear brake is the master cylinder. Your new brake line goes from there to the rear caliper. The other rubber hose supplies fluid to the master cylinder from the reservoir and is not under pressure.

I realized that today after thinking about it more.  Thanks for confirming!

[fastedmiami]

Not to be a thread jacker, but what does part #9 do?  Is it necessary to use it?  For example, I know that my race bike does not have this little clip anymore.  Should I be worried?