Is this a safe way to adjust the free stroke of disc brakes?

Since new, I have been bothered by the amount of travel on my Ultregra disc brakes. I have the reach adjusted around the middle of its range, but the travel still takes the levers with 1-2cm of the bars.

When they engage, they do so firmly, so I don’t think bleeding is an issue. Two LBS mechanics also say they are working fine. In this video, the guy forces some additional fluid into the brakes after they have been bleed. The mechanics say I run the risk of damaging my seals and to not do it. Thoughts? The link should skip over some other troubleshooting he suggests trying first.

That’s rubbish about damaging the seals.

1 Like

Overfilling is only temporary, as the pads wear, the dead lever movement would continue to grow until equilibrium is reached.

I haven’t watched the video but, traditionally, people remove the bleed block and squeeze the levers a few times and add more fluid. It’s trial and error, and of course new pads would mean cracking open to bleed again.

I never got on with the roadie hydraulics and the free stroke in particular, unfortunately. I use cable pull hydraulic hybrids and faff with it that way.

Edit: I just watched, and that’s effectively what he’s doing. I wouldn’t do it his way. I would pull on the syringe first, to create a total vacuum and get air out and bubble up, and then push in. If that’s what you intend to do. I would also remove pads and the wheel, in case you make a mess and contaminate the pads and rotor.


Great tip about drawing the syringe up to remove the air bubble. Thanks!

I would make sure you have adjusted the lever free stroke first.