Bleedin Brakes :(

[l05tb0y]

Hi all, I've changed the brake pads on my 2004 sherco but I can't seem to bleed the rear brake. Any tips would be cool.

Thanks Dave

[maxbikes]

you don't need to bleed brakes after changing pads.

[lamby]

Try reverse bleeding using a syringe on the bleed nipple and forcing the fluid back from the syringe to the master cylinder. Worth a try.

[l05tb0y]

you don't need to bleed brakes after changing pads.

You do when you cant get the pads in and you have to take the calliper off.

[dadof2]

The usual problem is that there is a high spot in the hose where air can't rise out of. Try positioning the bike so air rises all the way to the bleed nipple.

Back flushing with a large syringe can overcome this but not always as the hole in the master cylinder may be too small to permit a decent flushing flow rate.

You can get large syringes from vets or from medical supplies on Ebay - 2 for £6 last time I bought them a few months ago.

[0007]

Burp it at the banjo bolt, treat it like a bleeder

[l05tb0y]

OK ,so I got a 60ml syringe and filled it with fluid opened the bleed nipple and attached the syringe. I emptied the reservoir and tried to push the fluid through, but the pressure was too much and just a little bit went into the reservoir, and it was very hard to do it. Is this normal ? but anyway it didn't work as the pedal didn't get any harder. Am I doing something wrong.

[tony27]

It's possible from the sound of what you're saying that you don't have enough play in the brake rod & the piston isn't returning fully which partially blocks the port, a quick way to check if that's the case is to remove the brake pedal & try forcing the fluid through again.

Have you had the master cylinder apart, there is a spring above the piston which should return the piston. If you take the rubber boot off the piston should be resting against the circlip, is something worth checking out

The way I managed to bleed mine was to work from the opposite end, I pulled the reservoir off & fitted the syringe to the line in place of it, took a couple of syringe fulls of fluid pumped through with the nipple closed off when refilling to get a good pedal after exhausting the other methods I had available

[l05tb0y]

I tried that way of taking the reservoir off and forcing the fluid backwards, but it was the same too much pressure. I will take a look at the master cylinder.

Thanks Dave

[steve_earle]

I'll second Tony with the brake rod free play, Also check the master cylinder is returning fully as they very often get crud in them and people don't realise as the brake will still work but casues problems when re bleeding.

sometimes a blast with wd40 and a lot of rapid pumping will get it working if your in a rush to ride but a strip down of the master cylinder is needed to fix it long term.

[l05tb0y]

Got in from work tonight and tried bleeding it one more time and guess what, it only went and worked. yippee a working back brake, I might get out this weekend.

[lockie28]

blead from the banjo bolt on the master cylinder ..... then the banjo on the caliper then finaly the nipple on the caliper ..... 3 points