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Taylor1975
16-03-08, 03:43 PM
Has anyone had the problem off bleeding front brakes? all have been reconditioned and steeled braided hoses fitted but i still get the handle back to bar(it does stop). Ive bleeded it at top to bottom and bottom to top
i taken it to shops but they dont help.:smt093

Razor
16-03-08, 04:01 PM
Zip tie the brake lever to the bar over night and that might force the last bit of air out. I always did this before I started using a big syringe and some clear tubing.

21QUEST
16-03-08, 04:03 PM
Has anyone had the problem off bleeding front brakes? all have been reconditioned and steeled braided hoses fitted but i still get the handle back to bar(it does stop). Ive bleeded it at top to bottom and bottom to top
i taken it to shops but they dont help.:smt093

Most likely reason is air in master cylinder. You need to bleed it.

Plenty of rag to protect your pantwork etc, crack the banjo bolt open very slowly and just enough to be able to let brake fluid escape.
*Pump lever a few times, hold to bar, then close banjo(don't torque up properly yet)
*Pump lever a few times, hold to bar, open banjo slow and just enough to let fluid escape, then tighten(again, do not torque up preperly yet).
*should only need a few goes to get some resistance, now torque up properly and bleed as normal.


Cheers
Ben

ps: some people might suggest you put in new washers, nip lightly and then carry out the above(I wouldn't say they were wrong mind)......from my experience, I've never had a leak but what do I know :p ;)

missyburd
16-03-08, 06:56 PM
The way I do anything like this is to crack them slightly, pull in the lever slowly and see what comes out, there will likely be some bubbles, nip the banjo as the lever gets close to the end of its travel.

Do this at the MC, the splitter (if its 3line) and at the caliper banjo, then bleed the normal nipples again.


Yorkie_chris .... wrong account ... sorry.

northwind
16-03-08, 09:54 PM
I use a big syringe and a bit of plastic tube, and simply push fluid up the brake lines from the caliper- it's better to be able to do this without tools etc but I'm rubbish at it :smt090but this works for me. I do have a Mityvac somewhere which is a much more expensive and less effective way of doing the same thing.

Red Herring
16-03-08, 10:17 PM
Try turning the handlebars so that the master cylinder is at an angle, with the banjo end lowest. That way any air coming up the pipe and through the bango can carry on up inside the cylinder and up the intake pipe. It's also worth checking there are no air traps in the pipework where a horizontal pipe is sloping the wrong way.

Viney
16-03-08, 10:32 PM
Has anyone had the problem off bleeding front brakes? all have been reconditioned and steeled braided hoses fitted but i still get the handle back to bar(it does stop). Ive bleeded it at top to bottom and bottom to top
i taken it to shops but they dont help.:smt093
Many ways of bleeding brakes. Many different opinions. Many ways of naffing it up.

Like all things, i could give you my way of doing it. I have had my SV for 8 years, and in all honesty, i have only got the knack in the past couple of years!!

This is how i do it

Make sure the fluid is topped up
Put a piece of tubing on the nipple
Pump lever until its as hard as its going to get, then whilst squeezing, open nipple, count to 3, then close nipple, then release lever. Repeat until the lever firms up. reapet on otehr side along the way. Then over night tie the lever to the handle bar.

I always used to close the nipple quickly, but realised that the air doenst actully come out. It takes practice, but as i said, it took me a long while to get it, and im an experienced home mechanic when it comes to cars and suchlike.

flymo
17-03-08, 09:16 AM
....and another opinion. I did mine only two days ago and had it sussed. If the entire system has been empty as in your case, forget about touching the bleed nipples or banjos, just tighten everything up as it should be and make sure the bike is on the sidestand in order to position the master cylinder correctly.

Fill the res with fluid and then gently squeeze the lever. Let it go and wait a second then repeat. You should be seeing bubbles each time. Do this for 5 or ten minutes and you will eventually run out of bubbles. Give the lines a good tap with a spanner or similar to free any clinging bubbles and do teh lever again a few times. Give the bubbles time to flow to the top as they move slowly.

When you feel you are getting close (you'll feel) the lever stiffen up slightly, then move the bleed nipples. One side at a time, attach a clear tube that fits tightly over the nipple. Squeeze the lever and then loosen the nipple. Fluis should move rapidly into the tube carrying any bubbles from teh caliper with it. One or two goes should be enough but keep going until you see no more bubbles. Repeat with the other caliper.

I've always messed around with the bleed nipples right from the off but the above technique worked a charm. I raced the bike at the weekend and the brakes were totally superb!

Lozzo
17-03-08, 10:14 AM
Last time I fitted braided line set I put two bits of pipe on the caliper bleed nipples with the other ends into an old coffee jar, made sure the m/cyl was full and cracked off the nipples. Then I left it to stand and let the fluid work its own way down the lines. Every now and then I went back and topped up the m/cyl.

When I thought there was enough fluid down the lines I nipped the bleed nipples up and finished off bleeding the conventional way. Took about 15 minutes and virtually no effort.

I have a Mityvac that gets used when I'm replacing fluid in a system, but it's not too good at pulling fluid down a dry installation.