Brake failure light after front tire change

[jackronner]

Brakes seem to work fine, the wire on the left side brake unit seems fine. I did displace both units for the tire change, and have never had the brake failure light flashing ever before this. The speedo was working after the change. I have a feeling it's not a coincidence that it only started after the tire change, and that it is not attributable to the ABS brushes, etc. Any thoughts?

[David.]

The speedo was working after the change.

The speedometer is activated by a speed sensor located in the top of the final drive unit housing.

Any thoughts.

Has the ABS wheel speed sensor become damaged during wheel removal and fitment, it's quite a close fit to the sensor ring.

[jackronner]

Dave, How are you? I only mention the speedo after having reviewed other brake failure posts here, which often referenced it as a cause of the warning light. I confess I am confused as to the location of the speed sensor; if it's on the final Drive unit I'll take a look since I also replaced the rear wheel as well today. I assume from your reply that this would set off the warning light. BTW, what is the wire I mentioned on the front of the left hand brake assembly (which was where all my other bikes had the speedo cable)? It seems undamaged, but should I trace it to its upper connection, and with this also occasion a warning light? Again, the brakes seem to be working normally, but I haven’t tested the ABS with a panic stop since the tires are still slippery. Thanks.

[Doctor T]

Not being funny or doubting your abilities at all, but on replacing the front wheel is the ABS ring on the correct side? Very easy to fit the wheel the wrong way around.

[David.]

I am confused as to the location of the speed sensor on the final drive unit.

[David.]

What is the wire I mentioned on the front of the left-hand brake assembly.

ABS wheel speed sensor.

[jackronner]

Dr. T, ding ding ding, we have a winner! You are correct, sir! BTW, do not have any compunction about doubting my abilities, as you so kindly put it. I had the tires mounted and balanced by a professional, and took great care to observe the rotational direction, which he had backwards, but absolutely no care to confirm the ABS ring was on the correct side! I'm sure that's the source of the problem. Back to the wrenches. Thanks again, Doctor.

[jackronner]

Doctor T., It WAS on the wrong side, so I had the tire rotational direction remedied and remounted it properly, and Robert's yer muvva's bruvver - warning light's off. Cheers.

[Doctor T]

Well done. It's a easy error to do

[jackronner]

Dr. T, I see that you’re a don at Cambridge. That makes two dons that have figured in my motorcycle experience: My uncle Don started me on my road to motorbikes. We would visit Britain during the summers occasionally during the 1950s, when his family car was a 1936 600 cc Panther, with a two person side car. It even had a hand operated windshield wiper and sunroof! We’d all go on trips around Britain and I’d be riding pillion and having the time of my life. I bought my first bike in London, a ’71 Bonneville.

[Doctor T]

Dr. T, I see that you’re a don at Cambridge. That makes two dons that have figured in my motorcycle experience: My uncle Don started me on my road to motorbikes. We would visit Britain during the summers occasionally during the 1950s, when his family car was a 1936 600 cc Panther, with a two person side car. It even had a hand operated windshield wiper and sunroof! We’d all go on trips around Britain and I’d be riding pillion and having the time of my life. I bought my first bike in London, a ’71 Bonneville.

How dare you Sir, Cambridge I was at Oxford Uni.

[jackronner]

A gross calumny on my part; imponderable but I hope not unpardonable! Next thing you know, I'll neglect to use the Oxford comma! Certainly no way to thank the man who solved my problem.

[Doctor T]

A gross calumny on my part; imponderable but I hope not unpardonable! Next thing you know, I'll neglect to use the Oxford comma! Certainly no way to thank the man who solved my problem.

Sod the Oxford comma. In all my lecturing ive never bothered how my student used it or spelling mistakes. As long as i knew what they had written i still passed them. There is too much snobbery at Oxford.