Viewing 16 posts - 1 through 16 (of 16 total)
  • Not confident with hose shortening – question
  • nickfrog
    Free Member

    Hello, I have only done it once with TRP brakes which was super easy BUT this time I have to do Guide Ts.

    I have all the equipment required and I have watched this https://www.youtube.com/watch?v=dB5fTLKOmNQ

    However, my brakes don’t seem to currently be Stealth-a-majig (SAM) equipped which is not a problem as backward compatible (I have bought x2 SAM barbs and olives). I bought them new and pre bled and connected from Alpkit Ebya outlet.

    BUT, in the video what stuck me is that they disconnected the hose without any care and no fluid seemed to fall out. Is that because the levers they are disconnecting are already SAM and allow this.

    What will happen when I do the same with non-SAM levers? Won’t fluid escape from the lever or is there a way to avoid this even without SAM?

    Kramer
    Free Member

    Whenever I’ve done it, I’ve just held some paper towel around it as I’ve undone the compression bolt, and there’s been minimal leakage.

    Just be careful not to squeeze the lever when it’s disconnected.

    spooky_b329
    Full Member

    Remove wheel, pump the pistons out a bit, do the hose shortening and then after it’s all reconnected, push the pistons back and any tiny air bubbles you’ve accidentally introduced will get pushed back into the lever reservoir.

    You can also give the piston a tiny bit of pressure to get a bead of fluid on the hose end before reconnecting to the lever.

    timba
    Free Member

    They can lose the odd drop, or more if you tension the hose as you cut and the free end flicks mineral oil in your eye, not that I’d ever do anything that stupid of course 🙂

    andy5390
    Full Member

    I share the same concerns as the OP.

    Remove wheel, pump the pistons out a bit, do the hose shortening and then after it’s all reconnected, push the pistons back and any tiny air bubbles you’ve accidentally introduced will get pushed back into the lever reservoir.

    This an excellent idea (as long as I don’t pump too much)

    nickfrog
    Free Member

    Thank you so much. Will give it a go.

    Also, there is about 50% of dead travel on both brakes, which is a bit weird (coincidence?).

    Does that necessarily mean they need bleeding anyway? It’s frustrating if it’s the case as they’re supposed to be pre bled.

    I remember someone mentioning the “pull the lever a bit” trick with the wheels off to resolve that. Safe?

    reeksy
    Full Member

    I did one last week like this and had to internally route it on a new bike and didn’t need to bleed… just remember gravity and you’ll be fine.

    kelvin
    Full Member

    Also, there is about 50% of dead travel on both brakes, which is a bit weird

    Sram.

    oldnick
    Full Member

    You need a bleed if the brakes are a)spongy and/or b)need to be pumped up to get a firm lever.

    If they have a nice firm bite then hopefully there is a bite point adjuster or as you say, pump the lever a little with the disc out (when I’ve done it I just lowered the wheel a bit to get the disc out of the way, then it is quick to test and adjust until they are right and the same).

    Sometimes it is enough to elastic band the levers to the bars overnight (with bike assembled!). I can only think the seals relax into the “on” position and thus don’t retract the pistons fully in the morning.

    +1 for pumping the pads out a little before cutting hoses.

    Preferably do this job the night before you need the bike on a bank holiday, the extra tension adds a certain something when DOT fluid pees everywhere in the kitchen just as your wife walks in.

    kilo
    Full Member

    With just shortening, what I find to work well is just to not bother.

    Never had an issue with an over-long hose.

    nickfrog
    Free Member

    the free end flicks mineral oil in your eye, not that I’d ever do anything that stupid of course 🙂

    Preferably do this job the night before you need the bike on a bank holiday, the extra tension adds a certain something when DOT fluid pees everywhere in the kitchen just as your wife walks in.

    You guys crack me up 😂

    nickfrog
    Free Member

    Thanks to all the tips here, it went very well ….until it didn’t.

    The hose shortening was fine and the levers felt exactly like before afterwards.

    So I now know the dead travel issue is separate and I don’t need bleeding. I pulled the lever without a wheel on and then put it back on. Almost no dead travel, fantastic firm feel. Except I went a bit too far and there isn’t quite enough clearance to avoid constant rubbing, however hard I try.

    I tried to push the pistons back a bit with a tyre lever but I can’t. Any tips? Should I take the caliper off to do that. My tyre lever is perhaps too blunt and not thin enough. What else can I use?

    reluctantjumper
    Full Member

    Connect a tube to the caliper bleed nipple, crack it open a touch then try pushing the pistons back in. Also check that they are going back square to the caliper as any twisting will make them bind up and not move. Going carefully with a big flathead screwdriver can get you a bit of room to get the tyre lever in or anything wedge-shaped that’s nearly as wide as the pads can work too. If you think you can be really careful you could try taking one pad out to gain a bit of a gap but you do risk damaging the exposed piston if you’re ham-fisted.

    reeksy
    Full Member

    Or just open the master cylinder to avoid the risk of contaminating the pads.

    timba
    Free Member

    An old-fashioned flat, thin cone spanner is ideal for starting pistons back into the caliper. I don’t know how I know this 🙂

    nickfrog
    Free Member

    Cheers! I put some gaffer tape around the blade of a flat screwdriver in the end. I basically halved the dead travel now and the rotor is easy to centre.

    So all good but it shows how far superior the TRP Slate 4 (non EVO) are compared to SRAM Guide T at the same £70 price. A doddle to fit and shorten the hoses, far better lever build quality and ergonomics (the SRAM lever blade is of medieval construction).

    At the end of the day (or night in my case) what matters is how they perform on the trail as the TRP were OOS, beggars etc…

Viewing 16 posts - 1 through 16 (of 16 total)

You must be logged in to reply to this topic.