Brake bleeding, stupid question #5...

[engine]

HD manual says to have the hose on the bleeder screw, like normally, open the bleeder screw, depress lever/pedal, close bleeder screw, release lever/pedal. Repeat until no air bubbles are present.

Stupid question is..............Master cylinder cap on or off? They don't specify. I would assume ON in order to build pressure in the system while pressing lever/pedal.

No need to "pump" brakes, right?

I can vacuum bleed the system, too right (pull vacuum from bleeder screw and pull fluid through)?

sorry, bear with me guys... :frownthre

[willprevale]

The cap should be off.

[Albie1200]

I just changed over from black to chrome master cylinder on front. I left the cover off so I could refill as needed. I also noticed that after putting everything back together and filling cylinder and pumping the breaks the fluid wasn't really going down too well. I ended up using one of those vacuum pump deals. Once I used a hose clamp to secure hose to bleeder screw(the supplied adapters leaked air) it was a breeze! I actually noticed that the old fluid in the caliper came out before the new fluid started to.(Old fluid was brown, new is purple) I felt a little better about that after knowing all the old was removed from the system. Now I am going to replace rear fluid since it was so easy. One more point DO NOT SHAKE BRAKE FLUID BOTTLE!!!! I did that once and was close to impossible to remove air until I waited over night and rebled. I also just noticed your post, actually squeeze lever and hold, then open bleeder screw, close bleeder screw, then release lever pump a few times and repeat.

[Turbota]

Bleeding Brakes! :yikes

I installed braided stainless front brake lines on my bike. Of course the front brakes needed to be bled after the install of new lines..

I found the only way to bleed them is to pump/squeeze the front brakes about 1,000 times!

Keep filling the reservoir as you do this.

Yes ... your wrist and hands will get very very sore.

Speed bleeder valves are great when working on cars ... They suck when bleeding brakes on a Sporty .... they don't work!

[stevo]

OK .... I'll get a RTF up for brakes as it seems to be the same probs .... I'll do it in the next few days..

Ya don't need to pump it a huge amount of times ... there's tricks

[mikeLI_77]

on my last bike it said not to secure the cap but to place it over the resevoir after filling with fluid to keep any dust out of the system. i have heard that the systems that push your brake fluid from your caliper up into the resevoir are one of the best since they get rid of air faster since air will rise so the air gets pumped out faster than trying to suck it down with a vacum pump or just pumping it 100 times. last time i did it i had a friend hold the wrench on the bleeder valve and i would pump and tell her when to tighten and loosen the valve. always make sure to have a hose ontop of the bleeder valve that will run into a cup that is half full of brake fluid so you will not suck up any more air into the system. it only took me like 15 minutes to bleed the entire system. if you have dual calipers i would suspect it would take longer and may be harder to do but i have no experience with them.

[Moved On]

I've only done my front brakes once. I had my wife help at the caliper end with the wrench, straw (I didn't have a hose) and coffee can. After about a few hundred squeezes (with bubbles stopping after about ten squeezes), I couldn't figure out why I couldn't get any pressure. So I put the cover on and three squeezes later it was up to pressure and never had any squish to it afterward.

My wife said she'd never help me do that again because it reminded her too much of our sex life. I didn't see the analogy though :o

Gazza

[Chip]

What Turbota said is the way I went.

[neckball]

Somewhere I read instructions on how to "tickle" the brake line. You pull the brake lever just a small amount, it moves just enough for the piston to uncover the hole in the reservoir and then you hold it in that position. Then take a screwdriver, hold it by the shaft, and tap the line with the handle of the screwdiver. It seems to help the air bubbles work themselves up towards the reservoir, if you look you can see them in the fluid. I pumped 1,000 times after installing a S/S braided brake line and them I remembered the tickle trick. It made short work out of the process.