DesmoEddy Posted August 4, 2010 Report Share Posted August 4, 2010 Never had any problems bleeding brakes...until now. Have replaced the damaged reservoir from my eBay '99 R1 and cleaned 28k-miles-worth of crud out of the calipers. Basically the system was completely dry until I refilled the reservoir and tried to build up some pressure and bleed the system. What's happening is that the brake lever moves but I'm not getting any fluid out of the bleed nipples. Am using the traditional method - open nipple, pull lever, close nipple, release lever. Have also tried repeated pumping at the lever & holding it in before cracking open the bleed nipple but there seems to be no pressure there. I should add that I've fitted new pads and that the pistons are well back in there bores, but again I've changed scores of pads and never had a problem. Next step is to have the master clinder apart, but this seems like a drastic step considering there wasn't a problem with the brakes when I bought the bike (apart from a knacked reservoir). The braking system is stock other than a pair of braided lines. Grateful for any suggestions, Eddy P.S. just proof read the above and there are too many references to nipples and pumping, but what the heck. Link to comment Share on other sites More sharing options...
blow_away Posted August 4, 2010 Report Share Posted August 4, 2010 You can never have too many references to nipples and pumping as far as I am concerned.......... I use the same old school methods as you. It occurred to me that bleeding the brakes may put an extra years worth of use on the master cylinder seals. Start at the top, crack the master cylinder banjo open and make sure the fluid is moving. Progress on down the system, checking any joints that you may have. Drop the lever when you release it, wiggle the hoses, hit the calipers with a soft faced mallet, push the pistons back to forrce the fluid back into the reservoir. Sometimes I resort to removing the calipers, tying the brake lever back to the bar and leaving overnight, seems to work but I'm not sure why? Maybe something to do with straightening the path so that the air can move back up? Mark had a "backwards" method in the mag not long ago I believe, I can't remember the details but I'll see if I can find it. I think that next time I'm going cut the crap and buy a Mityvac Link to comment Share on other sites More sharing options...
kaighn80 Posted August 4, 2010 Report Share Posted August 4, 2010 agree with above sounds like an air lock stopping the fluid getting out od the m/c you may have to bleed every part of the system or use suction Link to comment Share on other sites More sharing options...
DesmoEddy Posted August 4, 2010 Author Report Share Posted August 4, 2010 First, this forum proves yet again that it's by far and away the best bike forum on the 'web. Second, thanks a million for the replies (and for their speed!). After having me tea and going back to it for another look I realised that the Nissin m/c has an obvious weak point in that there's a high spot in the system which will fill with air at the upper part of the cylinder where the banjo screws in. Bleedin' obvious in fact. My other bike has a Brembo 19/20 radial m/c which is oriented differently and IIRC (it's in crates in the loft) has a built-in bleed nipple. I can see now why there are m/c banjo bolts available with bleed nipples. I've taken the m/c off the clip-on, held it level and tapped it a bit and got bubbles flowing back into the reservoir, which points to the air-lock you all describe. Zakalwe - you in LA1-land somewhere? I'm LA6, between Carnforth & Kirkby. Cheers all, Eddy Link to comment Share on other sites More sharing options...
speedy sie Posted August 4, 2010 Report Share Posted August 4, 2010 home made break bleader..... clear tube pv wot ever,a bolt and a stanley blade.. pipe must be a tight fit round niple... put bolt in other end to seal up... then at bolt end pinch the pipe and put a very small split in pipe with blade... place bolt end of pipe in clear bottle,fill over the split in the pipe with break fluid.. open the break nipplt and just pup the leaver till you see all the air go through the pipe and run clear with fulid...then close the nipple job done,the split acts as a one way valve ,been doing it for years, Link to comment Share on other sites More sharing options...
alexp5 Posted August 5, 2010 Report Share Posted August 5, 2010 Am using the traditional method - open nipple, pull lever, close nipple, release lever. Other way round dude: pull lever, open nip, close nip, release lever. This works for me if things get stubborn: use a BIG syringe and a short length of tight fitting clear pipe and fill the system from the bottom, i.e. caliper bleed nipples upwards. This'll dislodge any air bubbles trapped in the fluid anywhere in the system, usually signified by a 'burp' in the MC. ...or get a Mityvac Link to comment Share on other sites More sharing options...
DesmoEddy Posted August 8, 2010 Author Report Share Posted August 8, 2010 Ladles and Jellyspoons You'll be pleased to hear that after a lot more pumping it's as hard as a rock. Thanks all, Eddy Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.