Stripping down Ultegra brakes?

[SerpicoUK]

Hi all,

I wonder if you can help me with a quick question/direction?

I'm trying to strip down, clean and rebuild my brakes. I can't seem to work out how to get the two pivoting arms apart.

Diagram:
http://techdocs.shimano.com/media/t.../BR/EV-BR-6500-1681_v1_m56577569830611830.pdf

Its basically taking apart 4,5,6,7.

There is a hex nut on the front that looks like it should undo. But it won't move. Is it just a case of getting a vice and applying more force or do I need to do something else first? Does it even come apart?

Thanks in advance,

Serp

 

[artemidorus]

Why do you need to strip them down?

 

[alfeng]

I'm trying to strip down, clean and rebuild my brakes. I can't seem to work out how to get the two pivoting arms apart.

Diagram:
http://techdocs.shimano.com/media/techdocs/content/cycle/EV/bikecomponents/BR/EV-BR-6500-1681_v1_m56577569830611830.pdf

Its basically taking apart 4,5,6,7.

There is a hex nut on the front that looks like it should undo. But it won't move. Is it just a case of getting a vice and applying more force or do I need to do something else first? Does it even come apart?

Yes, it comes apart, but you don't need to disassemble the calipers to clean them ... just dis-engage the spring (which you have apparently done) and you will have access to all the surfaces of all the "parts" that you probably want to clean ... as well as allow you to access the head of the bolt assembly which holds everything together.

BEFORE you try to unthread the central bolt, you have to unthread the fluted collar that is on the back-side of the caliper -- it is NOT numbered in the diagram NOR is the washer that is holding the spring in place [which is made to look like ONE "thing" in the diagram]... it is in front of WASHER #6 & behind the SPRING. There is probably a special tool for this, but if you are "gentle" with your wrench/pliers, you can loosen it without marring the finish ... the fluted nut is NOT particularly tight and so it should not require much force to loosen it.

IF you do remove it, before doing so, note how tight/loose the assembly is because that is how tight/loose you want it to be when you retighten everything --- that is, you want the arms to pivot smoothly after you reasemble the caliper!

 

[SerpicoUK]

Thanks for the reply alfeng. I thought that fluted bolt needed to be undone but obviously don't have any appropriate tool.

I think I'll probably forgo using some pliers on them.

artemidorus - As to why I wanted to strip them down...they were sticking so I thought I'd take them apart and give them a bit of a service...as I was taking them apart I thought I'd see how far I could take them down (merely out of interest).

Cheers,

Serp

 

[alfeng]

FWIW. For your future reference, if you use an adjustable wrench, the points of two flutes will rest on each flat ... so, you'll have four points of contact. The nut on the few calipers which I've taken apart have not been particularly difficult to remove; and, if you feel like you are exerting more force than you'd like, you can simply stop since you don't have a pressing need to disassemble the caliper.

NB. The half-yoke is also threaded, and that is certainly one reason why the fluted nut does not have to be particularly tight.