This might be a dumb question, but......

[patblkwell]

Ok, I am now in the process of restoring the 350X I got a few weeks ago and the front brakes were all messed up-both the caliper and the reservoir. I got another reservoir from a friend of mine and took it completely apart, cleaned it out, and installed a new spring/piston assembly to deliver brake fluid to the caliper. This is the first bike I've owned with the disc brakes....

HERE'S THE QUESTION, when you squeeze the brake handle, should brake fluid always come out of the brake line or just air sometimes? I filled up the reservoir with brake fluid and there are no leaks and what not, I squeezed in the brake lever several times and no fluid was dispensed from the reservoir?? This can't be right?? Also, I still haven't been able to get the pistons out of the caliper, I may have to find a higher source of air pressure to blow them out with than what I am using now..

[Bigred200]

Pat my best guess would be you should get fluid but Ive never had 1 either but it doesnt sound right to me either.

[dizasterzrfun69]

Ok, I am now in the process of restoring the 350X I got a few weeks ago and the front brakes were all messed up-both the caliper and the reservoir. I got another reservoir from a friend of mine and took it completely apart, cleaned it out, and installed a new spring/piston assembly to deliver brake fluid to the caliper. This is the first bike I've owned with the disc brakes....

HERE'S THE QUESTION, when you squeeze the brake handle, should brake fluid always come out of the brake line or just air sometimes? I filled up the reservoir with brake fluid and there are no leaks and what not, I squeezed in the brake lever several times and no fluid was dispensed from the reservoir?? This can't be right?? Also, I still haven't been able to get the pistons out of the caliper, I may have to find a higher source of air pressure to blow them out with than what I am using now..

So your saying when you squeeze the handle no fluid comes out?

If so it's real simple, you just need to bleed them. if so heres what you do. ( it may require 2 people) fill the reservoir with fluid, then you squeeze and let go of the lever a few times until it feels like it has built up a little pressure. Once it builds up pressure squeeze the lever and hold it. while your holding the lever, losen the screw on the caliper (looks kinda like a grease zirk) until the brake lever squeezes all the way to the handle bars (or as far as it goes). Fluid might come out and it might not. either way, tighten the screw back up (snug) and then let go of the brake lever. pump the brake lever again until it builds up a little pressure and do it all over again.

You will want to keep doing this until you have nothing but a steady stream of fluid coming out of the caliper for a good 4 or 5 times of doing that "cycle".

Well i hope this helps and it's what you needed, if not then hopefully someone will see it and now know how to bleed brakes.

Kevin

[patblkwell]

Hey, thanks for the tip on what to do....I'll have to try that tomorrow. I have heard about bleeding the brakes and all, but wasn't sure if I had to do that first to get the pressure started from the reservoir to the caliper. Are you talking about unscrewing the bleeder valve on the caliper when I squeeze in the brake handle? I'm still having trouble getting the pistons to come out of the caliper, but I'll try what you said tomorrow. Thanks for the advice man-

[dizasterzrfun69]

well the lever should build up a little pressure after you squeeze it a few times and then you losen the screw while you are still squeezing (holding) the lever. then the lever should move a little, once it does you will want to tighten the screw back up and then let go of the lever and do it all over again. If you cant even get the reservoir to build up a little bit of pressure then you will have a bad seal or something somewhere. As for the piston moving? I dont think it will move much, if at all, until you bleed the brakes completely


Kevin

[Vealmonkey]

As your bleeding your brakes, watch the caliper to make sure no fluid is coming out where the pistons are. The piston has small rings and if the rings are bad, they will leak fluid and never bleed down. If you try and blow air to brake your piston loose, place something over the piston so if it does break loose, it doesn't put out a window or hurt somebody or break something. When those pistons break loose they can do some damage. You can always try spraying some wd40 in where the piston is to see if it will help with any rust and spraying wd40 where the brake line goes into the caliper won't really hurt either, if it brakes free, you will have to bleed the brakes down anyway and this will help flush out any wd40.

[patblkwell]

I have tried using wd40 on the pistons and even filled the caliper with grease then put the air hose to it. I think I will have to find a more powerful air supply to get the job done. All I have is one of those red tanks that you can fill with air(doesn't have a compressor). Those pistons are really in there...just my luck haha.

[Vealmonkey]

did you try putting a c clamp on them and slowly tightening down to see if you can get them broke loose the other way?

[patblkwell]

Hey, I actually though about doing that....I was just worried that they might get stuck in even further. Worth a try though...

[1DEADPRESIDENT]

Hey PB, I just got done rebuilding my front caliper and used another Front Master Cylinder that I had gotten from another member. That combined with the new front brakeline made the job of bleeding the front Hairy at Best. If you have access to a vacum pump I suggest you try it. Be sure to check your bleeder screw also. If it is even the slightest bit loose you won't have get all the air out. My bleeder screw was loose so I used teflon tape to get mine tight and right. The instructions in your 350x Shop Manual for bleeding the brakes are great if you live in a perfect World

[kb200x]

somthing else that has worked great for me is to fill the reservoir full of fluid and very slightly open up the bleeder where there is only a very little fluid dripping. after that go have a beer and come back in thirty or so minutes and then go with the pump up the pressure untighten ect.... as dizasterzrfun69 was saying. Gravity is your friend. Do a search for bleeding brakes theres an old tread on it.

[350xfromhell]

hey guys,
when i replaced the brake lines on my bike the desk dude told me that i should replace all those little brass/copper washers whenever i take off the lines.even if you put them on,torque them down once i guess they crush and are not reuseable.also they won't leak fluid but they will suck in air.

just my 2 cents.