Maguras Bleed Attempt. Night 1.

...which has resulted in FAIL.


I understand the principle of bleeding them and have tried my first attempt tonight...


I have the gear and oil, followed numerous tutorials BUT even after the third attempt I squish the lever and the pads move but they dont contact the rim

It doesnt appear there's air on the system - but something's surely amiss?

Anyone with any guidance?

If with the wheel in place you pull the lever and the lever makes a solid contact then they are bled if the slave cylinder does not return then remove the weel and pads then use a silicon spray on the pistons as the seals are a bit sticky

Its as if I need to put more oil into the system?

1) Pull lever

2) Pads move and just make contact with rim

3) Not really usable as a brake. FAIL.

To check if they've got air in all you need to do is have a look to see if the pads move as soon as you put pressure on the lever. One very important thing to do before you bleed them is to make sure that the pad clearance adjuster is fully wound out. Also it depends upon which lever you've got as to the method of bleeding. The older levers have to be set horizontally when bleeding whereas the newer levers have to be set at 20 degrees below horizontal.

If they're not making contact with the rim are they adjusted correctly? You can move the slave cylinder closer to the rim. I know some of the more modern Maguras have offset brackets. If you still don't get rim contact after moving the cylinders all the way in then you can swap the fixing brackets around. I've had to do this numerous times with DH/4X bikes due to the extra width of the rear end.

2) Pads move and just make contact with rim

Click to expand...

err....ok Jez, wind all adjusters out, fit new pads and set them up 2mm from the rim each side at the correct angle........what happens now?

is the feel at the lever frame flexingly solid or is it mushy :?

if it's mushy you ain't set 'em up or bled 'em right

These are the original race lines.

I shouldn't have to adjust and pad position as they were fine before....

I pull the lever and, yes the pad only begins to move when about half depressed. This means there's air in the system right?

This is what I do...

1. Syringe with oil, no bubbles plugged into brake slave. I have a catch container at lever end and squeeze the syringe until oil starts flowing out of lever bleed hole.

2. I then pop the screw back in the lever end then remove the syringe and replace the bolt at that end.

I take it that the brakes in question are the ones pictured in your avatar?

Is the lever horizontal? If you tap the hose with something while bleeding the brake it may help to dislodge any air. It can also help to have the bike tilted up (like it's doing a wheelie). This helps the air move upwards.

As I said before make sure that the 2mm allen bolt to adjust for pad wear is at its loosest setting.

I have found that sometimes I ended up bleeding 3 or 4 times before it was done.

ah haha, good luck, these bad boys are uber fun to play with

Fun! Fun???????

lol

I'll try the vertical wheelie trick next and see if that helps.


My garage floor is covered in mineral oil btw.

hah!

Take it to a shop. Will be done in a day. You will be clean and relaxed.