I can't seem to get my brakes to firm up. I've used a mytivac and all the air is out, but the brakes are still mushy with steel lines. I've bled them at every bleed screw, including the master cylinder. They dont seem to close all the way when pumping. Any ideas?
Are you bleeding both calipers at the same time? You only need to bleed from the calipers if you do it right. Just make sure you do not let the reserve go empty. I still do it the old fashio way. 1) calipers closed, fill reserve, pump brake lever until hard. 2) open calipers,....close calipers, fill reserve, pump brake lever until hard. 3) repeat until no bubbles in the bottle where the excess fluid from the caliper is draining to.
the vac works great but you may have to stick a zip tie on the end where it connects to the caliper nipple.....sometimes if it is not real tight it will suck air there
Buck; I just put a new master on my 01 gsxr, thats what you have isnt it? It took a while to get it done, but the advice given above is spot on. I pumped the lever hard a few times, kept the lever depressed a little, opened the bleeder a crack and continued pulling in the lever. I also tightenede the bleed bolt as i was pulling the lever in to help insure no air got sucked back in. Make sure the tube you are connecting to the bleeer valve is secure, some folks put a little grease on the connector to ensure its airtight, ive never done this though. I then did the lever trick vernigh and bled the master, though i didnt see much air coem out of that. good luck
Buck, try flicking the brake lever rapidly. Open the master cylinder cover so you can see in there. Now just start flicking the brake lever quickly, like you're picking at a guitar. As you're doing this, look inside the master cylinder and check for bubbles rising. Also, zip tie or bungy your brake lever closed over night. A lot of times any air in the lines will rise out.
Are y'all serious? I just got out of another discussion on another board about the very same thing... Please tell me this old wives tale isn't true... Where is the air going to "rise to" and why will it only do this with the lever strapped to the throttle?
one thing you might want to check is the crush washer at the banjo bolt. i had changed my lines to steel last season and couldn't figure why my brakes felt like mush the following day. as i pulled the lever i noticed a very very small amount of fluid coming out between the crsuh washers. if it is coming out then air is beoing pulled back in. so i changed out the washers and also installed a bleeder at the top of the resovoir. i bled the brakes and waited until the next day to bleed them form top and they felt great!!! don't know if that helps or not but i figured i would through it out there cya tony
The important bit here is the "overnight" part not the "zip tie" part. Sometimes the air gets suspended as micro-bubbles in the fluid. Just waiting overnight to let the micro-bubbles settle into a big bubble, and then bleeding again, helps.
This makes a great deal more sense. I have been in a lot of pits, and wandered around a lot of AMA races and have never seen a zip tie on the brake lever as part of the crew's daily prep...
non monoblock calipers suck...I.E.Suzuki..they flex and have a mushy feel. And are a bitch to get the air out of them. I take a third brake pad and install it in the caliper and hold the caliper sideways off the bike with the bleeder up and bleed them that way.
Be the air bubble grasshopper... Once you have a reasonable lever, letting the system set for a while will let the air trapped in suspension form a larger bubble. Air bubbles will want to travel up towards the master cylinder...why fight it? Look at your particular motorcycle for areas that a bubble might be trapped...ie: a brake line union or a master cylinder tipped so that the banjo bolt is the high point etc... Here's the trick. Reposition components as necessary so that an air bubble can easily travel up the line and slowly push the caliper pistons in. Fluid will travel up towards the master and bump the air bubble out of it's home. Pump up the lever/pistons as needed and repeat till no air bubbles appear in the master cyclinder. Rear brakes are sometimes more easily bled off the bike... Keeping the lever compressed overnight will block the fluid intake port and not allow any air to escape.
Please go to page 102 in the new April RRW. There is a nice picture of the AOD bike with a zip tie on the brake lever trying to get the air bubbles out. In fact, the whole article is about brakes and brake bleeding. Quote from the article; "A cable tie on the brake lever holds the master cylinder open to allow gravity to fill the calipers and to let air escape upwards in the system..."
