Jump to content

brake bleeding woes

Recommended Posts

i replaced the front brake line on my 98 kx 250 i know how to bleed brakes but i just cant seem to get any pressure i worked on it for an hour and ahalf any tips suggs would be most helpful:banghead:

Share this post


Link to post
Share on other sites

Keep pumping... when I did mine it took maybe 3 hours. Once you get it leave it ha...

Share this post


Link to post
Share on other sites

Yep, keep pumping...I took apart my caliper and it took about 2-3 hours of pumping/bleeding before it felt good during the bleeding process.

Share this post


Link to post
Share on other sites

mine took about 45 minutes. it helped when I took the caliper off and had the the bleeder nut facing up to get any air in the caliper out quicker and kept pressure on the brake pad with a screwdriver. it was to the point that there was no air coming out but wasn,t building pressure. thats when I used a large screwdriver between the pads and twisted it to keep pressure on the pistons and it built up line pressure within a minute. Then install the caliper (you may need to push the pistins in some to get the caliper back on) and bleed as normal. Or you can pump the brakes for 3 hours like some and watch the pistons go in and out without building pressure. I believe you need back pressure for the master cylinder to create pressure. Make any sense.

Edited by Assassin5150

Share this post


Link to post
Share on other sites

An hour??? 45 Minutes???:thumbsup:

Sorry, I don't mean to laugh, but you guys are making a simple job much more difficult than it has to be. If you're trying to fill an empty brake line and/or caliper by pumping the brake lever, you're going to work much harder than necessary to get the brakes bled.

Before you attach the line to the caliper, fill the caliper with fluid from a syringe. Then attach the line to the caliper. Go to the top of the line, and fill it with fluid from the syringe before you attach it to the master cylinder.

Now tap the caliper and lines with something like the handle of a screwdriver, starting at the bottom and working your way up to the top. Then you can reverse bleed the brakes to get the air out.

You'll be done in less than twenty minutes.

Share this post


Link to post
Share on other sites

I had the same issue. Just take the lid of the main reservoir off and literally pump it like a thousand times. Tap the brake line every 100 pumps or so and you will get pressure. Keep the reservoir topped off. You will see hundreds and hundreds of bubbles float to the top. Just keep pumping! it should take 10 to fifteen minutes. After you get some pressure, then bleed the brakes like we all normally do.

The really dumb side of it? (on my part) My manual said to the the exact thing i just said. It took me doing everything else first before finally turning to my manual:bonk:. haha

Share this post


Link to post
Share on other sites

Ok I had the same problem a while back. This is what i came up with. Take some type of old soap dispenser bottle (the type with a hand pump) and attach a piece of carb hose to the end of the dispenser. Make sure its clean and fill it with brake fluid. Open the bleeder valve and push the other end of the hose over it. With the top resovor lid off, pump the dispenser until fluid comes out the top. Then bleed as usual. Worked for me

Share this post


Link to post
Share on other sites
Ok I had the same problem a while back. This is what i came up with. Take some type of old soap dispenser bottle (the type with a hand pump) and attach a piece of carb hose to the end of the dispenser. Make sure its clean and fill it with brake fluid. Open the bleeder valve and push the other end of the hose over it. With the top resovor lid off, pump the dispenser until fluid comes out the top. Then bleed as usual. Worked for me

Till your brake started blowing bubbles ha...

Share this post


Link to post
Share on other sites

When you think you've pumped enough, do a little more, haha.

Pump it up real good and zip-tie the lever to the throttle overnight, in the morning all the bubbles will be consolidated (hopefully at the top of the reservoir).

Share this post


Link to post
Share on other sites

I recommend buying a cr style brake line. My old brake line(stock) on my 03 kx 125 had a horrible front brake. I bled them out several times but i think its cuz of the way the line wraps under the caliber.

Share this post


Link to post
Share on other sites

mine took about 45 minutes. it helped when I took the caliper off and had the the bleeder nut facing up to get any air in the caliper out quicker and kept pressure on the brake pad with a screwdriver. it was to the point that there was no air coming out but wasn,t building pressure. thats when I used a large screwdriver between the pads and twisted it to keep pressure on the pistons and it built up line pressure within a minute. Then install the caliper (you may need to push the pistins in some to get the caliper back on) and bleed as normal. Or you can pump the brakes for 3 hours like some and watch the pistons go in and out without building pressure. I believe you need back pressure for the master cylinder to create pressure. Make any sense.

Share this post


Link to post
Share on other sites

I tried for over 2 hours then read your post. I actually left the caliper on the bike and used a large flathead screwdriver to press the Pistons in. Like you said a minute or two was building pressure. Thanks. Good trick. ....Had some bike mechanic telling me to use a syringe. This worked easier.

Share this post


Link to post
Share on other sites

i just went to dollar store a bought a basting syringe...put a pc of vacuum hose on it that fits the bleed valve too....and wahlah! 30 secs....done

Share this post


Link to post
Share on other sites

With a few bits and parts reverse bleeding is the easiest. Took me nearly an hour to bleed my brakes the first time on my KX a few years ago. That's when I said eff it and made a little kit to reverse bleed.

Share this post


Link to post
Share on other sites

I wasted at least 1.5 million pumps and about 4 hours of my lift fighting with my front brake.  Then I wised up and inspected the master cylinder to find that the seals were damaged. 

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Reply with:


×