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View Full Version : FYI: Front Brake Bleeding


98lee
04-05-2007, 09:20 AM
A while back, I replacing the front master reservoir on my wife's K75S. While the system was open, I also put speed bleeders on the front calipers.

Because the system had been opened in three places, I expected it to take a while to bleed. But not a half an hour! I kept going back and forth between the front calipers. I wasn't getting much air, but I was getting NO "pedal". I tried the conventional "up down" method on the brake lever and I also tried my vacuum bleeder. Still not much air but NO "pedal".:banghead

It seemed like the master was not bleeding properly, like when you don't "prebleed " a master on a car. But I am not aware of a procedure to "prebleed" the bike master.
Besides, I hadn't had this problem when I rebuilt the master cylinder last September. Everything bled fine with no problem.:dunno

Up to this point, I had had the bike on the centerstand with the front wheel pointed straight ahead to facilitate going back and forth between the two front calipers.

For some reason, I turned the front wheel all the way one way (sorry, I don't remember which way, but you only have two choices). I got a "pedal" in two pulls!!!:clap

Obviously the angle of the master, when the wheel is pointing straight, was trapping an air bubble in the master.:groovy

So, If you ever have a problem when bleeding the front brakes, try turning the front wheel all the way to one side (or the other).

jdiaz
04-05-2007, 09:31 AM
When you are done bleeding, leave the steering at full lock to the left overnight. You'll notice a difference in the morning.

I've also noticed that almost all new BMWs with remote fluid reservoirs have upper bleed nipples included.

98lee
04-05-2007, 12:45 PM
When you are done bleeding, leave the steering at full lock to the left overnight. You'll notice a difference in the morning.

I've also noticed that almost all new BMWs with remote fluid reservoirs have upper bleed nipples included.

Thanks for the tip.

I had thought that the successful bleed was at full left lock. Your comment confirms this.:thumb

I'm glad I have older BMWs. I'm not too keen on the idea of "bloody nipples"!!!!!:uhoh