Shortening Shimano brake hoses without bleeding?

Cave_Dweller

I've read a few different ways to do it and does it really work with all shimano hydraulic brakes? I need to shorten my rear brake hose.

One way of doing the job without bleeding said to take the calliper off and pump the lever to push the pistons out a little, cut the hose to where you want it and reconnect. They also said to do this with the reservoir cap off so that when you push the pistons out, if there is any excess air in the system it will go into the reservoir.

Whether or not that's true and works fine I don't know. I've always just bled my brakes when doing this job but I don't have a bleed kit anymore and done fancy buying one just for a one off job now and again.

If it makes any difference these are my exact brakes.

cooldad

It does. Except when it doesn't.

Giraffoto

Cave_Dweller wrote:

One way of doing the job without bleeding said to take the calliper off and pump the lever to push the pistons out a little, cut the hose to where you want it and reconnect. They also said to do this with the reservoir cap off so that when you push the pistons out, if there is any excess air in the system it will go into the reservoir.

Whether or not that's true and works fine I don't know.

Worked for me. Get the proper Shimano funnel to screw into the reservoir cap, because if you've done this properly the oil may overflow otherwise.

Cave_Dweller

Giraffoto wrote:

Cave_Dweller wrote:

One way of doing the job without bleeding said to take the calliper off and pump the lever to push the pistons out a little, cut the hose to where you want it and reconnect. They also said to do this with the reservoir cap off so that when you push the pistons out, if there is any excess air in the system it will go into the reservoir.

Whether or not that's true and works fine I don't know.

Worked for me. Get the proper Shimano funnel to screw into the reservoir cap, because if you've done this properly the oil may overflow otherwise.

Cheers. My reservoir cap is a bit strange. I take it off and there's a rubber cover underneath it. If you take that rubber cover off you can see the fluid. Will I still need that funnel you're on about?

It seemed a lot more simple with my set of Hopes. you just take the cover off and can see the fluid straight away lol.

cooldad

No different brakes.

The Rookie

You don't need a funnel with those, just a syringe and small hose, easiest brakes in the world to bleed and I can do mine in 2 minutes dead.
1/ Rotate lever on bars so the cover is horizontal
2/ Remove cover and diaphragm
3/ Use syringe to empty reservoir in lever
4/ Draw fluid into syringe and point downwards and ease plunger in until fluid gets to tip of hose
5/ Remove plastic cap from bleed nipple on the calliper
6/ Fit hose to nipple, keep syringe pointing down
7/ Loosen nipple
8/ Push plunger down to push fluid through until either the reservoir is full or you get to the point where you may push air trapped in the syringe into the system
9/ Tighten nipple, remove hose, refit cap
10/ Top up reservoir if necessary so that when fitting the diaphragm you get just a small amount of leakage and trap no air
11/ Refit diaphragm and cap.
12/ rotate level back to desired position.

Giraffoto

Cave_Dweller wrote:

Cheers. My reservoir cap is a bit strange. I take it off and there's a rubber cover underneath it. If you take that rubber cover off you can see the fluid. Will I still need that funnel you're on about?

It seemed a lot more simple with my set of Hopes. you just take the cover off and can see the fluid straight away lol.

You know what, I don't think I ever looked in the hole when I took either the cap off or the funnel out. My experience is with the 596 Deores, although I believe that the lever is identical in almost every way apart from the design on the reservoir cover to the XT and SLX brakes of the same year. I'd guess (note that word!) that what you see is a rubber diaphragm that's perforated somewhere to allow oil to be added from the top cap.

lm_trek

On the newer 2013? models, its stupidly easy even i managed it. Shortened the hose on my slx front and rear, even ordered another set of olives so i could re-trim the front one again as i didn't take enough off and didn't realise until i had fitted it back on. After 2 shortening still didn't require a bleed, fair play to shimano for doing this as my avids just a diaster.

The Rookie

No, they are totally different, pre funnel and the Mx65 style (I have the same age M765's).

Deore similar to above
http://techdocs.shimano.com/media/techd ... 604542.pdf

Cave_Dweller

Thanks all. Hopefully my new headset comes tonight so I can put the bike together properly that I need to shorten the hoses on. I have a syringe and some piping for aquariums so I'll make my own bleed kit for standby.

I don't know what model Deore's my brakes are. I just know they came standard on my old bike in 2007. I've always bought Hopes as an upgrade but didn't bother with these because they are pretty good. Can easily emergency stop with only one finger.

Cave_Dweller

Another question. Does my model of Deore brakes have a barb that connects into the end of the hose? If so can I reuse it or will I have to buy a new one to attach onto the shortened bit of hose?

Cheers.

papertech202

Followed this and it worked a treat for me.

http://www.epicbleedsolutions.com/blog/ ... -bleeding/

Cave_Dweller

Yeh looks like I'll have to order a new barb'd connector for it, just in case. I don't want to get half way through have to leave it because I've missed something.

Cave_Dweller

Done the job and was a piece of cake. I have to buy new connectors and olives though to shorten the hoses but at least I know it can be done without bleeding and what to do next time when the bits come in the post.

holiver

How easy is it to cut the hoses? Will a sharp knife do or is a hose cutter recommended by those who have done so?

I am thinking of purchasing the current model Deore brakes (M615), which would likely need the hoses shortening.

Thanks

The Rookie

If you use a brand new Stanley knife blade and cut flat onto a chopping board, it works just fine, DON'T use the tip of the blade.

holiver

OK cool. Thanks

JBA

papertech202 wrote:

Followed this and it worked a treat for me.

http://www.epicbleedsolutions.com/blog/ ... -bleeding/

I shortened the brake hoses on the Deore brakes I fitted to my son's bike a few weeks ago using the guide above and it was easy.
I used good cable cutters to cut the hoses and then used a small allen key to open up the cut end.