| Author | Message | ||
     Toniportray |
I've just gone through the experience of bleeding the front brakes and replacing the fluids. I'm wondering if I did it right though. As I understand it, you begin to pull in the brake lever while opening up the bleed valve, then when the lever is pulled in 3/4 of the way, you close the bleed valve thing. I ended up doing that at least 20 times before I started to get any pressure in the front brake. I have no idea how much fluid I ended up wasting just from all that pumping and releasing. The front brakes work now, but I have to pull in the lever 3x further than I used to before I bled them and replace the fluid. How can I get it tighter? Is it normal to go through the open/close lever pull/release process as much as 20-30 times to build up the pressure, or was I missing something? Lastly, is it normal to loose so much new brake fluid in the process? | ||
| Swampy |
OK, couple of things going on here. Hydraulic brakes, you need a lesson in hydraulic theory. For all practical purposes fluid does not compress. Air does compress. So hydralics is like Sex, you pump fluid in and it either swells up or drains away. You need to get all the air out of the brake fluid, the master cylinder and the caliper. The fluid can be gravity bled, you do not need to pump it to get it to bleed. Remove the master cylinder cover, remove the fluid being careful not to get it on anything and wipe it out with a lint free cloth, open the bleeder fitting and attach a hose to the fitting and place the other end in a glass jar so you can see what is coming out of the end in the jar, refill the master cylinder with clean, fresh brake fluid, then go do ten push ups, check the level in the master cylinder and watch the end of the hose to see if any bubbles come out, when no more bubbles come out close the bleeder fitting leaving the hose on the fitting, Pump the brakes till they get hard and give it one hard squeeze and hold it to compress any bubbles that may be in the line, caliper or fluid, open the bleeder and watch for any bubbles, when they clear close the bleeder refill the master cylinder and that should do it. | ||
| Gearheaderiko |
First, I'm not disagreeing with Swampy. However, the Blast front brake is notorious for not bleeding back to normal. You can pump it, gravity bleed, run a hose from the bleeder into fluid, etc. It aint coming back! Usually, I get it to the point where you've got it.You have brakes, but not much. As long as they work (safely)they'll bleed themselves back to normal within a week of riding. Tips: Excessive pumping gets you nowhere. Once you can get it to gravity bleed (ie after 10 push ups you can see the level has moved-if you've pumped a lot, it wont move), keep at it through a couple of master cylinder fulls and you may have it. After the traditional brake bleed (not excessive-just what would be normal) spread the pads apart in the brake caliper (carefully with a screwdriver while its on the bike) and then slowly pump up the brakes again. That will usually get the pressure back. | ||
| Joey |
Or you could do it the way I did. I just lived with it being squishy, and it worked itself out after a couple hours of riding. I'm thinking vibrations did it. Make sure your squish isn't so bad that the brake won't stop you in an emergency before you hit the road! Now, if I'm just replacing fluid, I mostly empty the master cylinder, then start adding new fluid before I start getting air. That keeps me from going through the nearly impossible bleeding job... | ||
| Swampy |
Its probably caused by microscopic air bubbles in the new fluid all collectivly making it feel soft. Probably from pouring it in the master cylinder and air adhereing to the parts. After getting no bubbles I will close the bleeder and pump the brake solid hold it and release it. Then I tap on the caliper lightly with a hammer to try and get the bubbles all clumped up, then bleed it again. | ||
| Toniportray |
Thanks for the prompt responses. I'm yet again reminded of the hospitality of motorcycle forums. The Blast will stop fine and promptly, but it takes 1/2 to 2/3 a full squeeze, whereas prior it kicked in full brake at 1/6 a squeeze. As stated, it got to a point during the bleed where it just wouldn't get any firmer. I'll post back over the course of some riding and see let everyone know what happens. And thanks Swampy for the sex analogy. That helped to really "visualize" the hydraulic pumping action.  | ||
| Gearheaderiko |
Oh ,yeah,I forgot about the tapping trick(I only did that a week ago!). Thank God I'm not the only one posting here! Swampy, the problem (with the Blast) is many times you cant even pump up the brakes to even get a firm (or any) lever at all. Sometimes, just getting any lever is good enough and better left alone. It'll come back with riding. | ||
| Rockstarblast1 |
well tonight i had to take the brake line off the master cyl. and flip it around to make it work and look good with my new bars.... long story short i tried breeding the breaks and got no where i have no front brakes at all. and i got impatient lol and called it quites for the night... granted i only did it for about 5 min. but still wayyy longer then it ever took me for any car ever!!! i guess ill try again tomarrow any tips? other then whats stated above? | ||
| Gearheaderiko |
Normal! It doest leak at the master does it? It can be dam near impossible to get the front brakes back. (Some get lucky). Tips: If you get any kind of brakes back, even if its low, but will still stop you,STOP BLEEDING, thats as good as it gets. With riding in about a week or less the brakes will be back to normal. Gravity bleed. Pull of the master cover and run a hose into a jar from the caliper bleeder screw. 'Pump' the lever just a little to get the pressure up, crack the bleeder and wait. Make sure the master doesnt go empty. Can take a LONG time. Bleed the best you can then with the caliper on or off, force the piston back into the caliper bore via the brake pad (avoid unnecessary force on the rotor). This almost always works. Avoid a lot of pumping of the lever, this usually makes things worse. And again, if you get any kind of feel at the lever, STOP. Its not likel;y to get any better without gravity bleeding or piston pushing. Yeah I know this is mostly a repeat of above! | ||
| Rockstarblast1 |
See this makes me not even want my blast ne more. It just seams like crap now. That shouldn't be right... and I font feel safe with little brake..... but as stated above right now I don't have any... | ||
| Swampy |
Start over again. Make sure everything is assembled correctly. Loosen the line at the master cylinder until fluid leaks out, tighten it. loosen the bleeder and use a rubber hose that goes into a glass jar with at little brake fluid in it(so you can see bubbles)keep the resevoir filled and watch for bubbles. After you don't see any more bubbles, tighten the bleeder, pump the brake, release and open the bleeder again(this will compress the microsopic air bubbles and bring them to the top) When it clears up, close the bleeder and try it. If it is still spongy, make sure the hose is not swelling. All bets are off if you are using the wrong fluid or using anything other than new fresh fluid. Make sure all the mechanicals are OK also, wheel bearings and master cylinder and the like. And if you want to get rid of it, I'll take it.... | ||
| Swampy |
Its not rocket science, its like sex, "You pump the fluid in and either it swells up or it runs out" Hydraulics 101 | ||
| Rockstarblast1 |
brand new dot 4 safe synthetic brake fluid.. everything worked fine before i took it apart, and i know its back together right... i didnt even get time to try it today i was tryin to figure out how to make my own air intake for it | ||
| Gearheaderiko |
All the advice you need is right here! The Blast front brake line will make you feel like a complete idiot. Its normal! If you'd told me you were going to pull the line, I would have guaranteed you'd have this problem. I've been through this many times. You dont need the full brake lever travel to stop. If you remember how it was, you probably only used a third of it. If all you get is 'enough', it will come back to normal, usually in a couple days. Follow Swampy's advice (and/or mine). Go slow, I've let it gravity bleed for hours! The synthetic DOT 4 is compatible with regular brake fluid, right? (DOT 5 synthetic isnt). Did you try pushing the brake pads(piston) back into the caliper? PS again 'pump' the lever slooowly. This is not like anything you've bleed before. | ||
| Reuel |
If only I had read this the first time I changed my brake fluid. I had this insane idea that I wanted to get all the old fluid out before I put new fluid in. My brakes didn't work normally for weeks! Mostly normally within a few days, but weeks before they really felt like new. Had to change the caliper a few years ago, and went through it all again. Big fun! I found that usage is the best method. | ||
| Rockstarblast1 |
Not sure I went to the store and the mostly had dot 3 syn. They had a few dot 5's and then one that was dot 3 and dot 4 syn.... so I asked if it would be ok and they assured me I'd be fine. So that's what I'm using.. My buddys car takes dot 4 and that's what he uses in there also | ||
| Gearheaderiko |
It should say on the container whether its compatible, probably is, but there is some special stuff out there that isnt. At this point all the old brake fluid should have been flushed out from all the bleeding (a good thing)! | ||
| Rockstarblast1 |
it is, it says right on it dot 4. ok so i bled like almost the whole bottle through and well....... i have a lever! but not till its all the way back and touching the throttle grip! and if im going like 25 mph i need a good distance to stop with just the front, if i use front and rear id keep it under 35 i deff dont feel safe riding it on the main roads so idk what to do! i really want it fixed but dont feel like spending a billion bucks taking it to a buell dealer | ||
| Gearheaderiko |
Did you try pushing the brake pads (piston) back into the caliper? Remember: DO NOT frantically pump the lever. Slowly. | ||
| Reuel |
Have you tried just pumping the brake handle slowly about 10 times to see if pressure builds up? If it does, just keep doing it. It'll work its way back to normal. | ||
| Rockstarblast1 |
While bleeding I let it gravity bleed thru about 4 resivors full of brake fluid, while doing that I did pump it maybe 10 times total. And yes very slowly... once I finished bleeding I did pump them that's when I got the very little braking that I have now... and yes I pushed the piston (brake pads back) into the caliper. (It should be pushed back with the bleeder valve open or closed? Open right?) iv don't everything right I'm not dumb and I'm very mechanical esp with cars idk what the probelm is other then I have a bike that I can't even ride now | ||
| Ezblast |
Do some very slow riding around the block, constantly squeeze/pump the lever - a few trips should work it out - if it continues to be difficult, then I would suspect a caught air bubble that needs dislodging from your line. EZ | ||
| Rockstarblast1 |
If that's the case how do I get it outta there? I took it up my street and back down once but didn't keep hitting the brakes... ill try again today... its really startin to bother me/ upset me it was easier to pull a motor out of a chevy 2500 and rebuild it then this!!!! Lol | ||
| Rockstarblast1 |
Thought I posted a reply but doesn't seam to be here. Ill try that if it doesn't work how do I get the air bubble dislodged? When I was bleeding yesterday there were quite a few big ones but then they went away. | ||
| Gearheaderiko |
Bleeder screw CLOSED. Push the pads (piston) back into the caliper, bleeder screw closed. Try it again! I can almost guarantee it will at the very least give you a usable front brake. "Have you tried just pumping the brake handle slowly about 10 times to see if pressure builds up? If it does, just keep doing it. It'll work its way back to normal.""if it does" are the key words. If nothing is happening you are wasting your time. Really, its not that big of a deal if you know to expect the problem. Then you'll move on to the next step without wasting time. Not too long ago I completely flushed the entire front brake system and replaced it with Dot 5. Knowing the likelihood of the problem, it wasnt any big deal. Doesnt matter if you have an air bubble or not, with riding it will work itself out. | ||
| Gearheaderiko |
PS ANY time you crack the brake lines there is a very good chance you wont get it to seal again-it will leak. Keep new washers on hand or avoid cracking the lines. | ||
| Rockstarblast1 |
yes iv pumped it more then 10 times slowly after i got done bleeding it. and it slowly after about 20 slow pumps pushed the pad all the way back to the disk... and thats where its at now with week stoping power. My driveway has a pretty steep hill and my front brake itself cant keep me from rolling down it. and about it leaking i read that before on here and figured if it leaked i would just go buy some new washers but so far so good.. no leaks that i can see.. | ||
| Rockstarblast1 |
ok so after running a whole tank of gas though the bike with this brake lever problem, i decided id crack it open and bleed it again. a few more bubbles came out.. closed it back up but its still the same... this is getting very fusterating | ||
| Ezblast |
Then something is holding air in your system, check your line, bolts,washers, bleed valve, because something is not right. EZ | ||
| Swampy |
I had a problem with the Big Kids car just recently, he blew a rear wheel cyllinder, and I repaired and bled the rear brakes but to no avail, he still had a pedal that would go to the floor but could be pumped up. I figured the rear brakes were out of adjustment, so I adjusted the brakes really well but the brake was still the same, so I replaced the master cylinder thinking he was riding around with no fluid and bottomed the master cylinder piston in the bore and ruined the seal, so when I was bleeding the front brakes right off the bat a BIG slug of air came out of the front caliper, and immediately the pedal was firm, I had overlooked that it could have been the front brakes giving me the symptons I was experiencing. The moral to the story is really this, Hydraulics is like sex, you pump fluid in, and either it swells up, or it drains away.....wait a minute, I just posted that. |
