One Man Brake Bleeding

AdrianS

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This is a general question not specifically linked to a particular bike.

Quite often when I want to bleed brakes there is no one else available so have to do it alone.

Used a piece of pipe with a one way valve at the end, dunked it into a jam jar with some brake fluid in and opened the nipple about 1/4 to 1/2 a turn and carefully pumped the fluid through.

What worries me is the introduction of air into the caliper via the loosened thread of the nipple. I have bled many cars and bikes often on my own and the brakes seem to be ok after bleeding but I cannot be certain no air has been introduced back into the system.

Thought about putting some grease around the base of the nipple to act as a seal but not sure if this will be ok.

Any suggestions apart from getting someone else to help!
 
I get my wife to get me a 60 cc syringe from work and push the fluid through from the bottom up. It has never failed to work yet.

As long as you close the nipple with the brake lever held down you will not draw air into the system.

Hope this helps

Tom

Sent from my GT-I9300 using Tapatalk
 
Personally I don't think it is much of a problem, and your experience in bleeding brakes over the years has shown this to be the case.

However I do understand your concerns. Usually when I bleed brakes, I lock off the nipple after the down stroke and before the release stroke, re-opening it again at the start of the next down stroke. But that's OK if you can reach the nipple and lever.

There are companies which provide speed bleed nipples which have a check valve installed, and which have a plastic coating added to the thread which prevents any air from tracking up the thread. But they are pricey.

http://www.speedbleeder.com/

The subject has been much discussed on the american forum.

http://www.advrider.com/forums/showthread.php?t=900262

You could try a very small piece of PTFE thread tape. Only to the thread and not anywhere near the sealing faces.*

It is important for safety that when the nipple is closed. That the taper cone of the nipple meets with the tapered cone metal surface of the brake caliper, and that the two metal faces have nothing between them that could be a source of failure. But you probably know that already.
 
I use a similar method to topcat except I suck the brake fluid into 100ml syringe after loosening bleed nipple. Done my 1150GS and Transalp recently using this method on my own - no problem at all, just have to make sure you keep an eye on the reservoir that it doesn't get too low
 
when ever i finish bleeding brakes i always tie the lever back to the bars and leave the bike overnight. Usually the air bubbles rise up through the open master cylinder valve into the reservoir so when you untie the lever you are left with a nice firm brake.
 
There is another way if you are not in a hurry ! ... static bleed.
Rubber pipe , over bleed nipple (tight fit please) - open bleed nipple .... and wait ..... drip , drip ....... drip

keep reservoir topped up needless to say.

gently close and torque nipple when finished.

PS , if your bike is upside down and the fluid reservoir is below bleed nipple ... this will not work :D

I have just flushed an entire system like this ... guess 3 hrs ish
 
I use one of those non return valve jobbies but I must admit, I generally do the nipple close / open dance when I've pumped it through and I see clean fluid in the jar. That said, for work I've just bought a bloody great six litre vacuum device for priming oil fired boilers so I may try that next time...
 
The brakes on my bike are servo/abs ones where I use the motor in the servo to push the fluid through. Not sure if it is ok to "suck" the fluid through with this system.

The idea of ptfe tape on the nipple sounds like a possibility but I would have to remove the nipple fully to do this properly - don't really want to do that.

Someone suggested to me coating the nipple/caliper joint with thick grease which should form a barrier to air entering into the system
but had not heard of that before and wondered if anyone else had heard of it; or am I just being too fussy about a problem that doesn't exist!
 


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