Having a hard time setting up the brakes on my wife’s cross bike – 105 shifters (7025s for smaller hands) on to xt calipers for the post mount – BH-90 hose.
Bled them up, down, and sideways and they’re soft as. Bite point on the bars, unrideable. Any ideas for what I might be missing, crafty techniques to try?

Feels like there’s an incompatibility with lever and caliper, but usaully there’s no problem mating a shimano MTB caliper to a road lever.

Does the lever have a big enough cylinder (or something) to draw enough fluid to work with the MTB caliper? If not, you won’t get it working as it isn’t moving enough fluid.

Or drop the wheel out, pull lever to bars to pistons move out and rebleed with pistons at that position instead of fully retracted.

That’ll mean less pad movement to rotor so less lever throw.

Keeping bike upright, tape or use an elastic band band to hold lever to bars,leave overnight, dont know how it works but it does on my brakes, every time

Are the calipers new? I know my 685’s (think that’s the number) had a recall for the same issue and they ended up replacing the calipers FOC.

Try this:

https://www.youtube.com/watch?v=piWBVDh1pTE

I’ve used this on two sets of Shimano road hydraulics and it’s worked perfectly both times. The last time was yesterday on some Deore levers with Ultegra flat mount calipers.

It works as it opens the system and puts pressure in the system. Air then travels upwards to the lever… removing it from caliper and hose. Top up fluid at lever to remove the air.

Does the lever have a big enough cylinder (or something) to draw enough fluid to work with the MTB caliper? If not, you won’t get it working as it isn’t moving enough fluid.

It feels like this is exactly the problem – but I guess it’s more likely that there’s some persistent air in the line somewhere. I think pumping the pads out a bit like you sugges,t and getting more fluid in will prob get them workable at least.

Everything is new, although the calipers are not a new design, prob a few years old.

It works as it opens the system and puts pressure in the system

It certainly puts pressure in the system, but pulling the lever closes the system, it doesn’t open it.

Try it – place the bleed funnel in, fill it and remove the plug. Now, pull the lever and open the bleed port, very little fluid will release. Now release the lever and fluid will flow freely from the funnel to the bleed port.

OP. Try and get the calliper directly below the lever (lowest point) and do the above and gravity bleed it. The head of pressure from the funnel will force air down to the calliper and the air will come out of the bleed port along with the fluid. Keep topping up the funnel until you’re happy no air is coming out.

Oh and are you sure all the hose bolts are properly tight? Even slightly less than bastid tight will allow air to be drawn into the system.

Thks Daffy – I have pseudo-sorted it by over-filling, and that has brought the bite point up to what feels like an OK set-up. Feels like something ain’t right with it but my wife will take it out tomorrow and see how it goes.

Had a terrible time with my road hydraulics at the rear. I am a crap mechanic though. Repeated bleeds after rides and vertical hanging (using the funnel) snapped the lever on and off quickly and flicking the hose has helped. A bit. Slowly.

It sounds to me like the OP’s brakes still have air in them. They can be right ****s to bleed, but that’s what it sounds like. The gravity bleeding as shown in the video above is generally very effective.

It works as it opens the system and puts pressure in the system. Air then travels upwards to the lever… removing it from caliper and hose.

It doesn’t open the system, it closes it. I think what probably happens is that it compresses the air in the brake hose which will make it easier for the air to float to the top because the bubbles will be smaller. Leaving it overnight gives the air time to work its way up the hose. When you release the pressure, the system opens and the air expands and flows through the master cylinder and into the reservoir.

Aye, sorry, wrong way round.

I find with a lot of air in the system that a reverse bleed helps more – syringe at caliper and a hard push of the plunger (making sure there is a syringe attached at the other end as well). Air tends to flow upwards easier than downwards.

I’ve had success with a difficult bleed rear XT by hanging the brake diagonal off the bike and used an old electric tooth brush to vibrate the bubbles out of any knooks n crannys.