Another Brake Failure

[Havan]

2003 Adv ABS/Servo.

9 miles into my morning commute & stationary on a slight incline at a set of traffic lights, rear brake engaged, the bike started rolling back. This wasn’t anything new as it often lets go briefly before reengaging soon after. But this time it didn’t reengage. I made a grab for the front brake but found no resistance & no braking – admittedly using only 2 fingers, I wasn’t able to fully apply the brake. I held it on the clutch and only at this point noticed the Brake Failure light flashing quickly.

The lights changed & I cut across to the inside lane but by this point the failure light had gone off & the brakes had returned. I pootled the last 2 miles to work, from where I got it recovered to Vines.

If it was going to happen, I think I was v. lucky that it happened as it did, but it’s certainly knocked my confidence a bit – it could have been a lot worse.

Will post the outcome for those who might be interested.

 

[Kropotkin]

Cue the good Dr Brake.


I hope you get it sorted, and glad it wasn't serious.

 

[Steve B]

Cue the good Dr Brake.

Conspicious by his absence recently or have we spoken too soon.......

Steve B

 

[Havan]

Update

Not sure if everyone’s getting a bit bored with the various brake failure threads but I thought I’d update this one anyway. Sorry to those of you who’ve had enough already.

Vines had the bike for a few days last week and in that time found a few things that might have caused the problem

1. Slightly damaged brake pedal, which was apparently sufficiently fatigued to snap as they tried to reshape it (I had a low speed, low side on a wet roundabout more than 15 months ago which might account for this).
2. Low battery charge – (bikes only just over 2 years old & I’ve put thousand miles on it in the last month).

So,
1. New brake pedal & bush
2. Adjusted brake light switch
3. Rear brake system bled
4. Battery charged
5. Integral ABS diagnosis procedure run (fault code 19 from what I can make of the print out I was given).

By the way, can’t fault Vines for the trouble they took to explain what was done & the detailed diagnostic logs they provided – not that it made a great deal of sense to me.

Picked up the bike on Friday & rode it gingerly home. Took the opportunity over the weekend to practice with residual braking, just in case. This came in handy.

On the Monday morning commute, I had the same symptoms again, this time while filtering through 3 lanes of traffic on the Hanger Lane Gyratory. That got the adrenaline going! Once safely in work I arranged with Vines to have the bike collected for a second look. I stupidly arranged that the bike be picked up from home to save me the trauma of public transport, so I’m sure it should have been no surprise that the servo let go twice more on the trip back. By this time, I was getting reasonably practiced in riding very defensively so no harm done.

Bike goes to Vines tomorrow. Will update this thread with the outcome (unless there’s no interest that is).

A few thoughts on residual braking.

The 20 minutes or so I spent practicing were very worthwhile. Though I never tried from quicker than 30 mph, residual braking will bring the bike to a stop but it doesn’t inspire much confidence. As others have said, 2 finger braking won’t do you any good & if that’s your usual practice, then in even a non serious situation the additional time needed to adjust your grip & the additional braking distance required by residual braking is very likely to get you into trouble. I think an important factor in braking is predictability. If you know you have weak brakes you can ride accordingly, but if you don’t know from one application to the next whether you have the excellent stopping power offered by servo/abs or the far from adequate alternative, I don’t believe you can ride with any confidence.

 

[simonm]

Re: Update

Not sure if everyone’s getting a bit bored with the various brake failure threads but I thought I’d update this one anyway. Sorry to those of you who’ve had enough already.

Nope not at all. It doesnt make pleasant reading tho.
I'm not sure I've heard of this type of intermittent fault before.
Keep us informed.