Got Sram Guide R’s on my bike. These the older (pre bleeding edge) and I’ve got a wondering bite point on the rear brake. The first pull on the lever almost goes back to the bars, but doesn’t feel spongy. After 2 or 3 pulls it feels fine again.

Am I right in thinking it’s not air in the system as it doesn’t feel spongy? I’ve bled them a few times which makes no different, though as these are pre bleeding edge, the bleed process is a pain to get right without fluid going everywhere. Also tried bleeding just the lever but it makes no difference.

Just gave the rear brake another bleed. No air in there at all. Some of the fluid in the lever was a little dirty so flushed it through from the calliper end. These are 6 years old now so wondering if it’s an issue with the lever internals? They are the RS version.

Other than the wondering bite point they feel great. Not had the common sticky lever issue and no fade on longer rides. Tried the zip tie trick overnight which made a difference for about 2 mins. I would just buy different brakes but I’d rather get these working consistently. I have the newer Guides on another bike which I had to bleed due to a torn hose and they have been perfect.

Avid always used to develop a fault like that as a result of the piston in the lever deforming. The rebuild kits are about £14.

Or it could be the caliper pistons are worn.

On the upside, SRAM sell most of the parts as spares. On the downside (especially at SRAM R / Shimano Deore level) it comes down to time Vs cost of just replacing with a new set.

What’s happening to the pistons? I’m wondering if they’re retracting too far. The first couple of pulls could reset them, but then they slowly retract into the caliper. Could be that the seals need replacing. The spares seems to be available, but I’ve never had to do it myself.

What’s happening to the pistons? I’m wondering if they’re retracting too far. The first couple of pulls could reset them, but then they slowly retract into the caliper.

That sounds like what is happening. I changed the calliper seals and pistons not long ago after they were sticking and not retracting.

Avid always used to develop a fault like that as a result of the piston in the lever deforming. The rebuild kits are about £14.

I think i’ll try that next. If i pump the lever fast, the bite point gradually moves further and further away from the bars but still feels solid when the pads contact the rotor.