How do you bleed the brakes?

[Greg Masters]

Dear collective wisdom

I'm pretty much through with doing a 12k service - but I haven't changed the brake fluid for a while and feel that it ought to be done.

The manual talks of bleed nipples and grub screws - this is all new territory for me. (The manual also mentions taking the handlebars off the bike, but I think that I'll pass on that).

Can anyone offer a description of what happens at the calliper end of this operation. In particular, when you've done the job and you remove the bleed nipple to replace the grub screw, what stops the fluid pissing out?



Greg

 

[Jimb]

Speedbleeders

My manual also states the same about bleed nipple installation but mine has nipples fitted ( Sept '02 ) with BMW EVO 2 brakes.

The clutch is bled at a hose positioned for the purpose on the right hand side and cable tied to the footrest hanger.

I have purchased some Speedbleeder nipples from the USA, these are self sealing spring loaded nipples for one man operation
http://www.speedbleeder.com/
I have them on my Honda Blackbird and they are magic, my '02 1150 has 8mm (SB8125L) in the front 6mm ( 6100) in the rear & 10mm ( SB 1010S ) in the ABS & clutch.

Just replace the existing nipples with these. makes changing the fluid a snap.

HTH

 

[Andy Leeds UK]

In particular, when you've done the job and you remove the bleed nipple to replace the grub screw, what stops the fluid pissing out?



Greg

If you remove the bleed nipple the fluid will piss out until you acheive a vacuum in the master cylinder or ABS modulator. What grub screw and why replace it?

Brake bleeding is done by two people (or one with long arms) with a length of brake fluid proof tube and a jam jar. You put the hose on the nipple and submerge the other end in the jam under clean fluid. Open the nipple 1/4 turn while your assistant brings the lever back to bars. You then close the nipple, let the lever go and if necessary take the top off the reservoir and fill it up. You repeat until all you are getting out is clean fluid (clear not yellow/brown) and no bubbles. Never let the reservoir empty if you can avoid it.

If you take the nipple out, fluid will come out and air will go in. If the air reaches the ABS modulator they are a sod to bleed and you will need a big medical syringe or vac bleed kit to force the air out the other way. Hence, I'd think about leaving the grub screw alone.

Andy

 

[Greg Masters]

Andy

I'm obliged to you, but, according to the manual, the set-up on my 2000MY 1150GS is not like anything else I have seen before.

The jam-jar technique you describe has been my MO for all of my adult life. I have poured more jars of brake-fluid down drains than I would care to admit.

The manual (which I don't have with me at present) clearly states that you have to remove a grub screw which appears to be located behind the bleed nipple. I'm reluctant to undo it until I am certain that I can complete the job!

Greg

 

[cookie]

the cheapo gunsons brake bleed kits sold in motor accessories shops for a tenner work quite well.....

IF (note: if is quite big)

there is a master cylinder top in the kit that fits your bike (not that likely).

or

you can get hold of a genuine mastercylinder lid & modify it.

when it's sorted it's the only cheap way of reliably bleeding the linked brake system on old guzzi's.

BTW one small problem: now, you think the manufacturers would have done something about this, but no, parts of the kit are damaged by brake fluid. no really so clean after use

 

[Andy Leeds UK]

If you loosen the bleed nipple and very lightly touch the brake, does fluid come out? As far as I knew, the R1150 before the introduction of the power brake system in MY2003 was just a basic two separate circuit system with ABS bypasses. The normal method works if you are not starting from zero fluid.

The grub screw behind the bleed nipple sounds like a fix for a higher pressure application like power brakes. If the bleed nipple can't take the pressure, they'd fit another pressure retainer behind it. You'd then need to undo the grub screw to allow flow. Having undone/removed the grub screw you'd bled as normal then try and remove the nipple keeping light pressure on the lever (but little flow) to stop air going in while you tightened the grub screw again. This would be a real mess of a bleed system but will work if the mastercylinder and ABS modulators are in the right places relative to the bleed. If you have to do it this way, I'd tie back the lever overnight afterwards to let any air that gets in self bleed into the reservoir.

No harm in loosening the bleed nipple and giving the lever a light sqeeze to see? Apart from that, it sounds odd.

Andy

 

[JohnnyBoxer]

How to bleed brakes??

Isn't that wot dealers do...................????

 

[Dave Hall]

A vacuum device is recommended if your bike has ABS. I`ve bought a MITYVAC (performance parts 0114 258 1151)

 

[MIKE R]

Halfords do a simple brake bleeding kit for about a fiver. It worked for my 11GS and Goldwing. When air somehow got into the 1150 system, these worked fine. Problem solved in under 10 minutes.

Mike

 

[Duncan R]

Bleeding the brakes

I had the same problem - you can't bleed the right caliper in the normal way because of the strange gizmo with the grub screw in it.
So, buy a BMW bleed nipple for the left caliper (not expensive), carefully unscrew the whole gizmo - some fluid will come out so don't touch the brake lever! Cover surrounding caliper & pads & wheel with cloth - clean up any spillage afterwards with warm soapy water.
Then quickly screw the new bleed nipple in and tighten up - (Don't forget to put the little rubber dust cover on the nipple before you screw it in) Throw gizmo in dark corner of garage.
EUREKA !
You can now bleed brakes in normal fashion.

Hope this helps, Duncan R

 

[City Slicker]

Re: Bleeding the brakes

I had the same problem - you can't bleed the right caliper in the normal way because of the strange gizmo with the grub screw in it.
So, buy a BMW bleed nipple for the left caliper (not expensive), carefully unscrew the whole gizmo - some fluid will come out so don't touch the brake lever! Cover surrounding caliper & pads & wheel with cloth - clean up any spillage afterwards with warm soapy water.
Then quickly screw the new bleed nipple in and tighten up - (Don't forget to put the little rubber dust cover on the nipple before you screw it in) Throw gizmo in dark corner of garage.
EUREKA !
You can now bleed brakes in normal fashion.

Hope this helps, Duncan R

Listen to the man here. This is the easiest way to bleed the front brake