brake pipes lengthenng....

[matata]

Just working on the wifes bike...cannondale hybrid with full hydraulic disc brakes. she like sit up and beg posture. I have used a fork stem extender and she's much happier. I need to extend one brake hydraulic cable. Is it difficult? Anybody else done it? Is it best left into LBS... Ta Nik

[peetee]

It would require a new brake line, olives and inserts and the fluid to be bled and re filled. If you have the right tools it can be done first time but it also can be frustrating and next to impossible depending on the model of brake.

[Brucey]

presumably she doesn't know if she likes this new position anyway? If so it may be prudent to try it out before modifying the brakes (which can be a PITA as mentioned above). Also note that the hose can often be re-routed so that you get more slack in a short hose, eg by routing the hose inside the fork blade or something like that. As long as the hose doesn't kink snag or rub it ought to be OK to ride.

cheers

[cycleruk]

Various Utube videos to give some idea whether to DIY or LBS :-
https://www.youtube.com/results?search_ ... +a+bicycle

[matata]

I might leave it as there is only 1/2 inch left in the stem...shed never notice it! ta nik

[thelawnet]

Various Utube videos to give some idea whether to DIY or LBS :-
https://www.youtube.com/results?search_ ... +a+bicycle

tbh it's quite an easy job but you do need to acquire the various bits & bobs.

Considerations:

brake hose - there is BH59 and BH90, BH90 is more rigid or some such and I believe mutually compatible but probably you would not want BH90 on one brake and BH59 on the other, so if you have BH59 already best to just stick with it. Around £5 for the hose with olive & insert

bleed kit - not expensive basically a syringes & a threaded funnel & mineral oil (do not attempt to reuse your old oil). Also bleed blocks are nicer for the calipers. The official Shimano bleed kit is a rip off and is just a syringe & threaded funnel https://www.wiggle.co.uk/shimano-disc-b ... eding-kit/ Ebay models have more bits than you need for less money https://www.ebay.co.uk/itm/Bicycle-Bike ... 4014431280

hydraulic brake oil - a few £ for 100ml which is far more than you need

hose cutter - cheap ones on ebay or aliexpress https://www.ebay.co.uk/itm/Rubber-Silic ... 3847012538 The pencil sharpener things in the kit above are for clamping the hose

Youtube videos -fine for the general bleeding theory (in one end out the other), but basically confusing & best avoided for the steps as your brakes probably different

Instead go to http://si.shimano.com and enter the brake number, then click the 'DM' which has an actually accurate to your brake model guide to the tools needed (allen keys, possibly an 8mm spanner, possibly 7mm socket) E.g. http://si.shimano.com/pdfs/dm/DM-MBBR001-03-ENG.pdf

[Airsporter1st]

Various Utube videos to give some idea whether to DIY or LBS :-
https://www.youtube.com/results?search_ ... +a+bicycle

tbh it's quite an easy job but you do need to acquire the various bits & bobs.

Considerations:

brake hose - there is BH59 and BH90, BH90 is more rigid or some such and I believe mutually compatible but probably you would not want BH90 on one brake and BH59 on the other, so if you have BH59 already best to just stick with it. Around £5 for the hose with olive & insert

bleed kit - not expensive basically a syringes & a threaded funnel & mineral oil (do not attempt to reuse your old oil). Also bleed blocks are nicer for the calipers. The official Shimano bleed kit is a rip off and is just a syringe & threaded funnel https://www.wiggle.co.uk/shimano-disc-b ... eding-kit/ Ebay models have more bits than you need for less money https://www.ebay.co.uk/itm/Bicycle-Bike ... 4014431280

hydraulic brake oil - a few £ for 100ml which is far more than you need

hose cutter - cheap ones on ebay or aliexpress https://www.ebay.co.uk/itm/Rubber-Silic ... 3847012538 The pencil sharpener things in the kit above are for clamping the hose

Youtube videos -fine for the general bleeding theory (in one end out the other), but basically confusing & best avoided for the steps as your brakes probably different

Instead go to http://si.shimano.com and enter the brake number, then click the 'DM' which has an actually accurate to your brake model guide to the tools needed (allen keys, possibly an 8mm spanner, possibly 7mm socket) E.g. http://si.shimano.com/pdfs/dm/DM-MBBR001-03-ENG.pdf

I think its important to highlight the need to ensure that the chosen fluid is compatible with the existing system. 'hydraulic brake oil' could be taken to mean conventional brake fluid.

[thelawnet]

I think its important to highlight the need to ensure that the chosen fluid is compatible with the existing system. 'hydraulic brake oil' could be taken to mean conventional brake fluid.

Shimano & Tektro use mineral oil. Sram use brake fluid.

I'm assuming Shimano brakes here, most likely to come on a cheap hybrid (a set of new Shimano hydraulic brakes with levers, calipers, pads, hoses is £30 at retail - no bleeding required if you are careful, but still good to have a hose cutter)

[Airsporter1st]

I think its important to highlight the need to ensure that the chosen fluid is compatible with the existing system. 'hydraulic brake oil' could be taken to mean conventional brake fluid.

Shimano & Tektro use mineral oil. Sram use brake fluid.

I'm assuming Shimano brakes here, most likely to come on a cheap hybrid (a set of new Shimano hydraulic brakes with levers, calipers, pads, hoses is £30 at retail - no bleeding required if you are careful, but still good to have a hose cutter)

Yes - understood. I was just thinking of someone who comes upon this thread in the future and wants to follow the very useful advice posted.

[zenitb]

I have tried three different ways of doing this.

1) LBS. I initially bought a longer brake hose and gave the job to my LBS to do. They completely messed it up and the (front) brake had no power at all both on their first attempt and when I took the bike back for them to fix. Worse than this they tried to argue that the brake was fine. I was really disappointed since I do try and support my local shop. I put this down to them being a predominantly roadie shop with no real experience of hydraulic brakes.

2) DIY. Since this was a Shimano (Deore) brake with human friendly fluid I bought a Shimano bleed kit on eBay, watched a YouTube video and did the job myself. All the air that the LBS had left in the system came out .. both at the top (bubbling into the top reservoir) and from the bottom caliper ( where you "tease" the bubbles of air out using the supplied syringe in the bleed kit, pumping in and out alternately). I took the brake lever and caliper off the bike to do this (so as not to get fluid on the bike the first time I did this) but this probably wasn't necessary. This resulted in a really powerful brake but quite a bit of my time being spent and a couple of weeks of the bike being off road.

3) Just get a complete new Brake with longer hose. When I needed to repeat the above job on my new commuter bike (in constant use) I simply ordered a new Alivio front disc brake lever and caliper, with long hose, ready bled and just replaced the old brake with the new one. This cost £28 from Tweeks and resulted in zero bike downtime and zero hassle. I was surprised how cheap the basic Shimano brakes could be bought for.

Option 3 was clearly the best option for me (cost vs time), but it depends how cheaply you can get the replacement brakes for your bike I guess. I suspect "matching brakes" will be a requirement of your build ??? Which brake is it (front/rear) and what brand/model is it ?

[NUKe]

If your not confident, and don’t have the tools use the LBS.cutting and fitting the banjos/olives are a bit fiddly. The bleeding with the kit is not a problem.

[thelawnet]

2) DIY. Since this was a Shimano (Deore) brake with human friendly fluid I bought a Shimano bleed kit on eBay, watched a YouTube video and did the job myself. All the air that the LBS had left in the system came out .. both at the top (bubbling into the top reservoir) and from the bottom caliper ( where you "tease" the bubbles of air out using the supplied syringe in the bleed kit, pumping in and out alternately). I took the brake lever and caliper off the bike to do this (so as not to get fluid on the bike the first time I did this) but this probably wasn't necessary. This resulted in a really powerful brake but quite a bit of my time being spent and a couple of weeks of the bike being off road.

If you buy all the kit, it doesn't take too long IMO

3) Just get a complete new Brake with longer hose. When I needed to repeat the above job on my new commuter bike (in constant use) I simply ordered a new Alivio front disc brake lever and caliper, with long hose, ready bled and just replaced the old brake with the new one. This cost £28 from Tweeks and resulted in zero bike downtime and zero hassle. I was surprised how cheap the basic Shimano brakes could be bought for.

Option 3 was clearly the best option for me (cost vs time), but it depends how cheaply you can get the replacement brakes for your bike I guess. I suspect "matching brakes" will be a requirement of your build ??? Which brake is it (front/rear) and what brand/model is it ?

'Alivio' is a bit vague, but note that Deore (and above) brakes are different in every respect with sub-Alivio brakes.

Shimano make:

* basic hydraulic brakes with basic pads, a few variations in levers (alu or steel, long or short levers (short levers are more expensive)) and correspondingly smaller or larger pistons
* 'Deore' brakes with different pads, hoses & off-road levers (a bit more grabby)
* 'SLX'/'XT' brakes which are basically the same as Deore but use ceramic pistons
* Touring versions of Deore & XT which use long standard (non-grabby) levers AND the larger piston size, so a bit more mechanical advantage
* Older road brakes, which are similar to the touring Deore
* Newer road brakes which use a new pad design
* XTR 9100 with the road pads
* 4-piston brakes in various models all basically the same

For a utility bike you can just buy the cheapest Shimano brakes with no issues. You might want to match the lever length to your existing brake if you are just changing one brake. Also the steel levers in IME in humid, tropical Indonesia rust. But they might not do in England, IDK.

For a MTB I'd look at Deore or possibly SLX.

These are a pair of brakes with the longer steel levers. https://www.aliexpress.com/item/BR-BL-M ... 44708.html

Note that they quote the hose length - 750mm and 1400mm. Some sellers provide much longer hose, which you will need to cut down to size. IME/IMO you will always want to cut the hoses just a little in any case, otherwise it looks sloppy. Cutting the hose does NOT necessitate bleeding the brakes, but you will want the hydraulic hose cutter thing, and the hose to be carefully clamped in place vertically so the oil does not come out. And you'll need a new olive!

As an example, this is apparently 1700mm. https://www.chainreactioncycles.com/shi ... prod135839

It will need to be cut.

These are a pair of two-finger-levered brakes

https://www.aliexpress.com/item/New-Shi ... 02087.html Here the hose lengths are 800mm and 1300mm so different again... £38

They are also short steel levers with the larger piston.