ABS bleed

[Mitch1100]

Can abs system on 1200s be bled without accessing control unit?

[1200boxer]

Can abs system on 1200s be bled without accessing control unit?

Yes it can.I bled mine using a diaphragm vacuum pump connected through a container to the bleeding nipples.It took no time at all.

[Sandy]

I am also interested in doing this job, but it is a bit worrying that the Haynes manual warns that bleeding abs brakes on the 1200s should only be done by a BMW dealer without saying why.

Does anyone know the reason and the chances of a diy-er getting it wrong?

[Tapio]

Can abs system on 1200s be bled without accessing control unit?

Yes it can.I bled mine using a diaphragm vacuum pump connected through a container to the bleeding nipples.It took no time at all.

Are you sure about this?
'cause my R11S has bleeding nipples on the control unit. If the R12 is the same, and you just bled the nipples at the calipers, then you only bled half the system.
My brakes have the electric servo.
Maybe the non-servo doesn't have nipples in the CU?
Maybe I should keep my mouth shut since i don't even own a R12?

Anyway, there's a very informative youtube clip on this matter, made by a guy from czec republic (don't worry, he doesn't talk in the video;-)). He bleeds the system on a 1200GS. I strongly recommend anyone wanting to bleed their brakes to watch it!

[KenG]

tried vacuum, and regular,

didn;t work for my 1150rt,
had to strip tank off and adapt 2 funnels on the top of the pump, hour and a half all done, and got a bit of fussy maintenance while i was in there.

rocking on the centre stand,, some mess to watch if you splash the paint, not saying how to suck eggs, but sort of needs weighted to the back and steering full lock to top up at the handlebars, a bug bit of plastic and a handful of rags.

[Dog Tyred]

rocking on the centre stand,, some mess to watch if you splash the paint, not saying how to suck eggs, but sort of needs weighted to the back and steering full lock to top up at the handlebars, a bug bit of plastic and a handful of rags.

Is this even English ?

DT

[Herb]

I had my brakes bled by an independent BMW specialist. He told me that they can be bled normally without accessing the ABS unit. The 1200s design is very different to the older machines and there is no servo.

The reason for the dealer recomendation is because in the service book BMW have added a diagnostic test, which I understand merely consists of a check for error codes.

FYI, I used Motoscot down Luton way. Very reasonably priced. A bit far for the OP but for anyone else locally I would heartily recommend him.

[1200boxer]

Can abs system on 1200s be bled without accessing control unit?

Yes it can.I bled mine using a diaphragm vacuum pump connected through a container to the bleeding nipples.It took no time at all.

Are you sure about this?
'cause my R11S has bleeding nipples on the control unit. If the R12 is the same, and you just bled the nipples at the calipers, then you only bled half the system.
My brakes have the electric servo.
Maybe the non-servo doesn't have nipples in the CU?
Maybe I should keep my mouth shut since i don't even own a R12?

Anyway, there's a very informative youtube clip on this matter, made by a guy from czec republic (don't worry, he doesn't talk in the video;-)). He bleeds the system on a 1200GS. I strongly recommend anyone wanting to bleed their brakes to watch it!

I found the whole thing very straightforward and,most importantly the brakes work perfectly.No servo on the 1200S.

[Tapio]

Ok, so only the servo systems have bleeding nipples on them.

Here's the video: https://www.youtube.com/watch?v=YLM25NYvlas
@4:00 you can see the nipples.
Note how he shows 1, 2 and 3 fingers while pointing at the nipples. He probably means that they should be bled in that order.
There's a part 2: https://www.youtube.com/watch?v=a1ktxY_bgQY

This system is exactly the same as on my BCR '04.

[Tapio]

The reason for the dealer recomendation is because in the service book BMW have added a diagnostic test, which I understand merely consists of a check for error codes.

Good info! Thanks!

Both the Clymer manual on my K100, and the Haynes manual on the BCR state that the brakes should be bled by a reputable shop, but neither says why. So I have been a bit worried about this. I mean, it's not exactly rocket science to bleed a brake system, whether it be servo or no servo so what am i missing?
Apparently just a technician with a laptop and an interface cable!

[Herb]

The reason for the dealer recomendation is because in the service book BMW have added a diagnostic test, which I understand merely consists of a check for error codes.

Good info! Thanks!

Both the Clymer manual on my K100, and the Haynes manual on the BCR state that the brakes should be bled by a reputable shop, but neither says why. So I have been a bit worried about this. I mean, it's not exactly rocket science to bleed a brake system, whether it be servo or no servo so what am i missing?
Apparently just a technician with a laptop and an interface cable!

l

My comments only apply to the 1200s. I think the earlier servo assisted bikes have a more complicated bleed procedure. Should not be beyond a competent home mechanic with the right tools though.

[Tapio]

Dammit!

Now you got me worried again!
guess I'll have to google it.

[Droptarotter]

Of course the manual states that it has to be serviced by a dealer..........they want your money!!

12S can be bled like a standard brake system.
I have done it many times........same with my HP2 Sport.

I will admit that I did bugger up a buddies 12RT.......removed all the fluid........installed new fluid, but could not get the air out of the system...........had to send him to the dealer........oops!

Bleed on!

[Corvus]

............. I mean, it's not exactly rocket science to bleed a brake system.............

Well, you say that, but.........

The basic science would have it that air will rise to the high spots. So, on a "normal" bike front system the high spots would be the reservoir and usually a high spot in the caliper chamber. That's usually where the nipple is sited. So, from a fresh fill, and allowing some time, so long as the path to reservoir rises all the way, we'd expect the system to self bleed, except for a small amount of air lurking behind the nipple. A small squeeze of the lever will shift this easily, with the nipple released in coordination.

My most recent dabbling with brakes was last year when I had converted my fzr1000 to renthal ultra low bars and fitted new braided hoses. The system was fully drained and all I did was simply fill from the reservoir and leave it overnight, checking the route to reservoir was constantly rising. In the morning I bled a small amount at the nipple. The brakes were superb.

Yet, on occasions when I've filled a water manometer ive sometimes noticed that "slugs" of air refuse to rise. Usually sucking on one end or even tapping clears it. On another occasion, earlier this year, I helped a mate set up some carbs and we made a little manometer connected to the float bowl drain. The idea worked very well and had great results in setting the floats, but, again, trapped air refused to rise of its own occord.

So what is the explanation for trapped air, given that there is no apparent obstacle preventing it from rising upwards? Is it that large "slugs" of air (as opposed to smaller bubbles) have too much drag?

Any thoughts.....

[nab 301]

............. I mean, it's not exactly rocket science to bleed a brake system.............

Any thoughts.....

Stiction I reckon...