Recently I had an accident on my bike, and my front brake 11-speed, front brake GRX 600 shifter isn’t braking well anymore.
The shifter took a bit of damage in the fall. Initially it didn’t shift, and I had to bend the edge of the lever arm (under the “X” of the GRX logo) outwards to stop it fouling on the inner shift lever. Shifting is fine now 🥳, but there are problems with the hydraulic brake.
The brake seemed fine. Pulling the lever it feels firm and brakes confidently. The problem is that the brake power fades and the longer you pull the lever the more it pulls in to the handlebar. Over a fairly short descent the lever can be pulled past the bar and the pads aren’t pressing on the disc anymore. Releasing the lever and squeezing again gives another firm/confident brake, which then eases off again.
My first thought was that this is a bleeding issue, so I picked up a bleed kit and gave it a go. This didn’t solve the problem, so I went through the bleed process again, to no avail.
There’s a good chance I’ve just failed to bleed it correctly. The handlebars are ridiculously aggressive gravel bars, so rotating the shifter to the correct position to “burp” it was a challenge. Also, I noticed a few tiny bubbles in the syringe of mineral oil (it was new).
Do the symptoms above sound like a bleed issue, or something else? All the advice I’ve found on the internet about air in the system and bleeding seems to suggest braking will be spongy but “pump up”. That’s not what I’m experiencing.
It’s seems impossible to get hold of Shimano GRX components at the moment, so I’m really keen to fix this even if it just holds me over until it can be replaced.