| Author | Message | ||
     Uly_man |
My front brake had "gone off" a lot so I washed off the disc and caliper. This helped a little. I then "flushed" the brake system, pistons pushed back, with new fluid and all is back to normal. Good bite and power with the EBC HH pads. I have no idea why this is but it works and seems to need it every 5k miles on this bike. | ||
| Desert_bird |
Procedure for flushing the system? DB | ||
| Uly_man |
Push the pistons back to zero and then put something between the pads and the disc to stop them moving. Take the cover/s off the master cylinder and clean. Put a small hose on the caliper nipple and direct into a bottle. Apply pressure to the brake lever and "crack off" the caliper nipple enough to let a small amount of fluid out. Once the lever hits the throttle grip re-tighten the caliper nipple. Continue to do this until the master cylinder has been re-filled twice. DO NOT pump the lever or let any air back into the system if possible as it will just need more work to clear any bubbles of air. | ||
| Desert_bird |
Easy enough. Thanks. Should air get into the system will it just make it's way up to the reservoir, or do I need to keep the reservoir cap open and pump it? | ||
| Hughlysses |
Push the pistons back to zero Before you push the pistons back in, you need to be sure and thoroughly clean all brake dust off the circumference of the pistons. Otherwise, the dust can get past the seals when you shove them back in and cause them to stick, which leads to other problems. DAMHIK I've used Q-tips, and old shoe string, and brake cleaner for the job. | ||
| Buewulf |
"do I need to keep the reservoir cap open and pump it?" You want to leave the cap off so that you can keep adding fresh fluid to it. The air is going to stay in the line but will bleed out as you continue the process. Don't let the fluid get too low in the master. | ||
| Desert_bird |
Got 'er done. Thanks. But after your apt. email, Hugh. What's in them pistons - if anything - is in there till next time. Hope there's no binding. Been meaning to get new fluid in there for like 2 years! I change b. fluid out of my cars every few years, but somehow though with relatively short lines, less weight and small volume of fluid, that it's not such a big deal on a bike. Let's see if braking is any stronger tomorrow morn. (Message edited by Desert_bird on October 19, 2013) | ||
| Krabykarl |
Stupid question; what do you guys use to push the pistons back. The manual says us a wood paint stirrer. As for flushing I used an automotive style brake bleeder kit. Basically it's a bottle and hose with a check valve to keep air from sucking back in through the calipers. That way you don't have to re-tighten the bleeder nipple. You can get one at just about any parts store for twenty bucks or so. | ||
| Griffmeister |
Of course, in theory, you should set the fluid level with new pads. Since disc brakes are self adjusting, the fluid level goes down as the pads wear. When you do put new pads on, you may have an overflowing reservoir unless you take some fluid out first. | ||
| Teeps |
Here's a link to a clever and economical way to bleed brakes. http://www.team-integra.net/forum/19-projects-diy- article-talk/166614-diy-1-brake-clutch-bleeding-to ol.html I've used a similar system, only difference, is my bleed bottle has a second (shorter) tube that allows the bottle to vent to atmosphere. The same could be done with the example above, or just leave the lid loose. | ||
| Shagg1970 |
For brake flushing I use a bleeder I got at harbor freight, it hooks up to my air hose and sucks the old fluid out of the bleeder. I run a full small bottle of fluid through topping it off as it sucks it out making sure it has fluid so that no air gets in the lines. it makes it so easy. Here is a link to the bleeder. http://www.harborfreight.com/brake-fluid-bleeder-9 2924.html Per the manual, brake fluid should be flushed every 2 years. That should be followed as fluid left in the system for several years will draw moisture from the air and corrode the brake system leading to expensive repairs. | ||
| Uly_man |
"will draw moisture (water) from the air and corrode the brake system leading to expensive repairs". In the case of alloy systems it will damage the alloys. You will see it inside a caliper if you ever take the pistons out. It looks like a white "gunk/paste" and is a mix of water and alloy. I have no idea why it works on this bike, this is the second time I have done it now, but it seems to work. Worth a try though. The front brake is ok but is marginal. It needs to be 100% all the time IE Perfect. | ||
| Hoover_uly |
One thing to also consider when bleeding brakes. Back in the day when I was working on cars that would now be considered vintage, we would never bleed brakes by forcing the piston of the master cylinder all the way into the master cylinder unless the master cylinder was new. The bore of the master cylinder was often corroded so when you forced the piston and seal far into the cylinder, where it never reached until the brake bleed or complete brake failure, the corrosion would damage the rubber seal on the piston and the customer was back in a day or two with the brake pedal on the floor. Whenever I bleed brakes I use short strokes on the pedal/lever to avoid the possibility of damage to the master cylinder. Other recommendations mentioned above still apply. Did this last weekend on 2 bikes and everything worked just fine. Perhaps there is some reason why this does not apply to modern vehicles but I still take the precaution. |
