Hayes 9 bleed problems.

Hi, got a quick problem with some Hayes 9s I’ve been bleeding. Basically, the lever comes back to the bar to start with, but then when you give the lever a couple of pumps it feels fine, and locks the wheel. Then when you release the lever it goes back to coming straight back to the bars.

When I bled them I just bled straight through – pushing fluid from the caliper straight through and out the lever, and there were no bubbles. I missed out the stage where you pull the air out of the caliper. If I did this stage, should the brakes work?

There’s no “pulling the air out of the caliper” with Hayes 9’s, you just push through from the caliper end.

You do need to rotate the lever so that the bleed port is pointing straight up and pull the lever a good few times while pushing fluid through from the bottom.

If you’ve had a couple of goes at that and it’s not happening, then the seals are probably fecked.

“11. Squeeze the fluid bottle firmly – forcing fluid into the caliper for a count of five. Stop squeezing – until the bottle returns to its natural shape. When the squeeze is
released, air should be drawn out of the caliper. Continue alternately squeezing the fluid bottle, for a count of five, and releasing until no air bubbles come out of the
caliper.”

That’s what I meant by pulling air out of the caliper, from the Hayes instructions.

Regards the seals, I’d assumed it couldn’t be that because the brake does come on when it’s been pumped?

As stevomcd really,
Never had a bother doing as so, touch wood.
Usually shut the bleed nipple before pulling lever, also flicking of the hose can assist air coming out the bleed hole while forcing fluid with syringe, i’ve never used a bottle!!
Try shutting off the caliper bleed nipple as you force the fluid through, even if with bottle!

Interesting, wonder if they’ve changed the instructions? Anyway, I’ve always kept maximum pressure on the squeezy bottle/syringe at all times and kept the pressure on while closing the bleed nipple. Works for me.

If you’ve got a slow leak through the seals, they’ll bleed up fine and be OK for a while, but once the fluid in the reservoir is depleted, they’ll start to need “pumped up” to work and then eventually just pull to the bars.

Mine have been great for years, but both have started to need bleeding every 5 minutes lately. New brakes for next season! (Actually, I’ll probably get new seals from Chain Reaction for tuppence and get another 5 years service out of them!).

Yep same here, i use two sets and don’t have any issues with bleeding them. Make sure that you have pushed the pistons in the caliper all the was back in using a flat head screwdriver. I’ve never ever had to even touch the lever whilst bleeding – just push the pistons back, rig it up and force a load of fluid through the system. A syringe is the best way BTW.

sounds like a problem in the master cylinder bladder.
pistons and hose wouldnt cause that problem?

I pressume the lever was pointed skywards?

Would echo the syringe thing – bottle in the Hayes bleed kit is pants. Im useless at these things but the syringe made it all OK! My problem is now that the lever just needs a slight touch and the brake is on full – guess I have too much fluid in the system?