STI + brake release

For discussions about bikes and equipment.
Post Reply
mark a.
Posts: 1375
Joined: 8 Jan 2007, 2:47pm
Location: Surrey

STI + brake release

Post by mark a. »

I have Tiagra STIs and wide-profile cantis on my bike. My brake blocks don't quite clear the tyre when removing the wheel, so the tyre must be deflated. Before I changed to STIs I had some Tektro levers which each had a button toggle that opened up the lever and hence also the brakes to give ample clearance. That was great.

Is there a solution that would give me the same effect but with the STIs? I've survived for years as it is, but it would be nice and I'm about to do some fettling and might as well do it while I'm changing cables, bar tape etc. Currently I have a hanger from the head tube on the front (no adjuster) and a Surly hanger (with an adjuster, but I don't think I've ever used it) on the back. The STIs themselves have no adjustment.

I don't even know what the term is I'm meant to be looking for. Brake relaxer? Brake release?
User avatar
meic
Posts: 19355
Joined: 1 Feb 2007, 9:37pm
Location: Caerfyrddin (Carmarthen)

Re: STI + brake release

Post by meic »

It is a pain isnt it?

The original design is that the brake release is a small lever on the dual pull caliper brakes that the STIs are meant to be used with. Campagnolo do it the other way around, I think.
I use a combination of adjusters that can be slacked off to give enough cable slack to disconnect the cable and some filing off of the cradle for the straddle cable's barrel.

There is possibly another problem that even when you have enough cable slack to open up the brakes, there still isnt enough room in the forks for the brakes to open into and you still cant get your wheel out!
Yma o Hyd
mark a.
Posts: 1375
Joined: 8 Jan 2007, 2:47pm
Location: Surrey

Re: STI + brake release

Post by mark a. »

Hmm, so I should look at some barrel adjusters? Ones with hopefully enough travel to make difference. The Tektro* solution was just so satisfying to use I wish it was somehow possible with STIs. I see the point about them being designed for shiny road callipers, though.

On the second point, luckily my bike is a Surly Crosscheck which has massive clearances so the brake blocks move well out of the way of my 32mm tyres.

(* I guess this is standard on all non-STI levers, but Tektro is what I had)
markfh
Posts: 210
Joined: 9 Sep 2013, 5:35pm
Location: Suffolk

Re: STI + brake release

Post by markfh »

What is available for bikes with threaded headsets is the Dia Compe 1254 Front Brake Cable Hanger 1 Inch with Quick Release (see https://www.sjscycles.co.uk/brakes/dia-compe-1254-front-brake-cable-hanger-1-inch-with-quick-release/). You may be able to find something similar.

Also some cantilever brakes come with a stradle cable one end of which is demountable so that you can unhook it to allow for a wheel change.

Do you know the make and model of you particular brakes?
Last edited by markfh on 12 May 2017, 4:15pm, edited 1 time in total.
User avatar
cycleruk
Posts: 6068
Joined: 17 Jan 2009, 9:30pm
Location: Lancashire

Re: STI + brake release

Post by cycleruk »

If you squeeze the canti' brakes together do you have a wire connection that you can unhook?
You'll never know if you don't try it.
User avatar
meic
Posts: 19355
Joined: 1 Feb 2007, 9:37pm
Location: Caerfyrddin (Carmarthen)

Re: STI + brake release

Post by meic »

On many set ups there isnt enough slack in the cable to unhook it. I needed to fit both an adjuster and to file some metal off just to be able to release the cable.

I fitted a cross top lever in order to provide the front adjuster, for the rear I could use a Jagwire adjuster in a cable stop.
Yma o Hyd
mark a.
Posts: 1375
Joined: 8 Jan 2007, 2:47pm
Location: Surrey

Re: STI + brake release

Post by mark a. »

The brakes are Kore something-or-other, whatever the shop had that looked closest to Tektro 720. As meic says, there isn't enough slack to release anything. There would be if there was some kind of lever or cable release mechanism... which is were I started :D
User avatar
meic
Posts: 19355
Joined: 1 Feb 2007, 9:37pm
Location: Caerfyrddin (Carmarthen)

Re: STI + brake release

Post by meic »

It is on Tektro 720's that I took the file to the cradle which holds the straddle cable's barrel.
They went a full 180 degrees around the barrel along the axis of the canti-arm, which means that it is considerably more than 90 degrees around from the line of the cable.
I figured having just 90 degrees of cradle, relative to the cable was quite adequate.
Yma o Hyd
mark a.
Posts: 1375
Joined: 8 Jan 2007, 2:47pm
Location: Surrey

Re: STI + brake release

Post by mark a. »

I'm not sure I'm up for filing my brakes, but I can see why it wouldn't be a problem. The Kore brakes really are similar to the 720s.

Trying to add more barrel adjusters, filing etc might be more trouble than it's worth. I've lived with the annoying brakes for a few years, so I suppose I can live with them for longer.
gregoryoftours
Posts: 2234
Joined: 22 May 2011, 7:14pm

Re: STI + brake release

Post by gregoryoftours »

A bit ugly, but maybe these would give enough slack to release the brake-

https://www.cyclebasket.com/m9b0s313p28 ... _Adjusters
User avatar
Redvee
Posts: 2469
Joined: 8 Mar 2010, 8:58pm

Re: STI + brake release

Post by Redvee »

gregoryoftours wrote:A bit ugly, but maybe these would give enough slack to release the brake-

https://www.cyclebasket.com/m9b0s313p28 ... _Adjusters


First saw those fitted to a £3k TT bike but that had lo pro integrated brakes in the forks/seat stays so was necessary.

meic wrote:for the rear I could use a Jagwire adjuster in a cable stop.


That's the solution I used with v-brakes a Dia Compe adjustable noodle up front.
markfh
Posts: 210
Joined: 9 Sep 2013, 5:35pm
Location: Suffolk

Re: STI + brake release

Post by markfh »

If you have almost enough slack in the straddle wire then a straddle wire with a shaped end can help with demounting and remounting the end of the straddle wire. The shaped end gives you a bit of leverage to help get the end out and back into the end of the brake.

e.g. https://www.sjscycles.co.uk/cables/cantilever-brake-straddle-wire-with-quick-release-nipple-350-mm-long/
Post Reply