Rear brake servo failure
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metropolis2k
- Posts: 380
- Joined: Sun May 26, 2013 4:47 pm
- Location: London
Rear brake servo failure
I've just finished the plumbing on my bike.
I ended up removing all the pipe work and hoses. I replaced it all with 3 new hoses by Venhill. It fitted well, except for the double banjo bolt for the front lines at the master cylinder which was too long. I shortened it by a couple of threads on the lathe.
I struggled a bit with bleeding the front, but left it overnight with the lever pulled back to the bar, and lo and behold the next morning I had good brakes all round.
I removed the ABS warning relay, the blue one furthest toward the back on the right hand side. However, I've just tried a quick scoot round the block, and whilst I now have good brakes and a working speedo, I still have a flashing warning light, and servo noises from under the tank.
Any suggestions?
Mark
I ended up removing all the pipe work and hoses. I replaced it all with 3 new hoses by Venhill. It fitted well, except for the double banjo bolt for the front lines at the master cylinder which was too long. I shortened it by a couple of threads on the lathe.
I struggled a bit with bleeding the front, but left it overnight with the lever pulled back to the bar, and lo and behold the next morning I had good brakes all round.
I removed the ABS warning relay, the blue one furthest toward the back on the right hand side. However, I've just tried a quick scoot round the block, and whilst I now have good brakes and a working speedo, I still have a flashing warning light, and servo noises from under the tank.
Any suggestions?
Mark
Why do cheap bikes never end up that way?
Having gone away and sulked for a while, I decided that my bike is no good parked on the bench, so I've had another go at a complete iABS removal.
To recap, I had removed all the hard pipework and factory hoses, and replaced them with braided hoses.
One for the rear circuit, and two directly from the front master to the front calipers. I also removed the ABS warning relay, the blue one rearmost in the r/h box.
After a bleed and an overnight stand I had working brakes. I still had brake lights and speedo, but I also still had flashing warning lights and servo noises. The pump was also trying to spit out the dregs of the brake fluid that I hadn't managed to extract.
After further rooting around the net, I found Steptoes method of dealing with the electrics which seems very elegent. But I'm chicken, when it comes to cutting up looms. I worried about the wiring colour codes and the possible damage that I could cause if I got it wrong or if the colour codes varied with models or years of manufacture.
I've gone with a method on a blog from Pelican.
I removed the whole ABS assembly held by three fiddly bolts and a large connector. The connector has a ZIF release mechanism, where a clip at one end is withdrawn and it actively forces the connector apart.
Once off the bike, I unbolted the electronic panel from the end of the unit, which uses 4 tri-wing screws held with Loctite.
This gives access to internal ribbon and Molex type connectors that I unplugged.
I folded up an ali cover, isolated the connector tails and fastened it on with M4 screws and silicon.
I reconnected the module and fastened it back into the space where the pump had been, then hooked everything back up. No pump noises, obviously, but still one flashing warning lamp, so I removed the headlamp for access to remove the bulb.
I still have to run round the block to check the speedo, but I think I've probably now won! I think I've saved a grand, and about 8lbs.
Mark
To recap, I had removed all the hard pipework and factory hoses, and replaced them with braided hoses.
One for the rear circuit, and two directly from the front master to the front calipers. I also removed the ABS warning relay, the blue one rearmost in the r/h box.
After a bleed and an overnight stand I had working brakes. I still had brake lights and speedo, but I also still had flashing warning lights and servo noises. The pump was also trying to spit out the dregs of the brake fluid that I hadn't managed to extract.
After further rooting around the net, I found Steptoes method of dealing with the electrics which seems very elegent. But I'm chicken, when it comes to cutting up looms. I worried about the wiring colour codes and the possible damage that I could cause if I got it wrong or if the colour codes varied with models or years of manufacture.
I've gone with a method on a blog from Pelican.
I removed the whole ABS assembly held by three fiddly bolts and a large connector. The connector has a ZIF release mechanism, where a clip at one end is withdrawn and it actively forces the connector apart.
Once off the bike, I unbolted the electronic panel from the end of the unit, which uses 4 tri-wing screws held with Loctite.
This gives access to internal ribbon and Molex type connectors that I unplugged.
I folded up an ali cover, isolated the connector tails and fastened it on with M4 screws and silicon.
I reconnected the module and fastened it back into the space where the pump had been, then hooked everything back up. No pump noises, obviously, but still one flashing warning lamp, so I removed the headlamp for access to remove the bulb.
I still have to run round the block to check the speedo, but I think I've probably now won! I think I've saved a grand, and about 8lbs.
Mark
Why do cheap bikes never end up that way?
Looks like I'll finally be mobile again - collecting my bike from Garry Webb on Saturday, all being well. He's bypassed the ABS for me. I decided to leave all of the ABS/servo stuff as it is - if a future owner wants to put it all back to standard then it's still there, should they want to.
Really looking forward to riding again!!
Nik
Really looking forward to riding again!!
Nik
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andy griff
- Member
- Posts: 650
- Joined: Sun Oct 05, 2008 8:20 pm
- Location: England
- Contact:
Collected the bike yesterday. Brakes took a bit of getting used to - no servo now, but lovely black braided hoses from Venhill, giving loads of feel. You have to apply more pressure but the brakes are great, with far more feel than before.
Was really lovely to ride again, and did a tank and a bit, and thoroughly enjoyed it. Only slight issue; I want something quicker now!
Big shout out to Garry for doing the ABS-ectomy. He did a really neat job, and even re-moT'd the bike for me. If you have any jobs you need doing I'd thoroughly recommend him - friendly, very knowledgeable, and extremely helpful. I'll post his details when I find his card...
Nik
Was really lovely to ride again, and did a tank and a bit, and thoroughly enjoyed it. Only slight issue; I want something quicker now!
Big shout out to Garry for doing the ABS-ectomy. He did a really neat job, and even re-moT'd the bike for me. If you have any jobs you need doing I'd thoroughly recommend him - friendly, very knowledgeable, and extremely helpful. I'll post his details when I find his card...
Nik
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andy griff
- Member
- Posts: 650
- Joined: Sun Oct 05, 2008 8:20 pm
- Location: England
- Contact:
Something quicker ?
Ah yes, Nik - something quicker you say ? Having been initiated into the Boxer sports family you now need the BMW R1200S - lighter, quicker and grin inducing and with no servo assisted brakes. But, no good for any pillion !
I was out on mine yesterday - very very happy with it. Crackles on the overrun when fitted with the Akrapovic which is very addictive - comfy enough and just that bit tighter all round. Isn't life full of difficult decisions ?
I was out on mine yesterday - very very happy with it. Crackles on the overrun when fitted with the Akrapovic which is very addictive - comfy enough and just that bit tighter all round. Isn't life full of difficult decisions ?
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andy griff
- Member
- Posts: 650
- Joined: Sun Oct 05, 2008 8:20 pm
- Location: England
- Contact:
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citizented
- Posts: 4
- Joined: Mon May 07, 2012 7:20 pm
- Location: Wiltshire
i-abs failure
Hi everyone, I posted back in April reporting a fault with my I-abs on an r1100s. I got it fixed in the end so I thought I would post up what I discovered.
I changed the battery but this didn't solve the problem. I got a gs911 diagnostics tool (you can't see abs faults using the led method, that just shows you engine codes), plugged it in and was able to see that the front brake lever circuit pressure sensor was fluctuating wildly. The sensor was obviously faulty and this was causing the fault with the unit.
I got a cheap 2nd hand I-abs unit on ebay, it looked exactly the same apart from the electronics at the end. I kept the abs cpu from my bike and fitted it to the new unit, installed it and bled the circuits and got the system working again. If the pressure sensors go again I plan to swop them out with parts from the spare unit I now have. I will also bleed the wheel circuits more regularly and I try to exercise the unit after a ride on a bit of gravel or grass.
The gs911 is a very good tool, you get the fault codes but more usefully get to read the real time values from the pressure circuits so that you can see where the problem lies. It is expensive though, I'm just hoping it can keep me out of the BMW garage when I get other faults!
Bye Ed
I changed the battery but this didn't solve the problem. I got a gs911 diagnostics tool (you can't see abs faults using the led method, that just shows you engine codes), plugged it in and was able to see that the front brake lever circuit pressure sensor was fluctuating wildly. The sensor was obviously faulty and this was causing the fault with the unit.
I got a cheap 2nd hand I-abs unit on ebay, it looked exactly the same apart from the electronics at the end. I kept the abs cpu from my bike and fitted it to the new unit, installed it and bled the circuits and got the system working again. If the pressure sensors go again I plan to swop them out with parts from the spare unit I now have. I will also bleed the wheel circuits more regularly and I try to exercise the unit after a ride on a bit of gravel or grass.
The gs911 is a very good tool, you get the fault codes but more usefully get to read the real time values from the pressure circuits so that you can see where the problem lies. It is expensive though, I'm just hoping it can keep me out of the BMW garage when I get other faults!
Bye Ed
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