ABS "fail safe" Mode

[slapnpop]

There's something missing in the story.

There are 4 attachment points for the front fender. The two large headed allen bolts at the front are obvious. There are also two bolts and nuts towards the rear. If these were loose, and coming out, it's possible for the bolt or nut to bind in the fork and against the wheel.

Was the front, or the rear of the fender contacting the wheel? The front of the fender should not cause a problem, but the rear of the fender binding against the incoming wheel, for whatever reason, might cause more trouble.

My overall outsider third party internet know it all conclusion is that something external to the braking system (or at least the ABS) cause the deceleration. The ABS light coming on was only because the ABS system sensed the wheel stopping, but could not correct the situation/brakes weren't active/whatever else it didn't like about the situation. I would inspect for further mechanical issues in the front wheel before concluding everything else is fine, and it was the ABS's fault.

 

[DaJuice]

Thanks for the ideas Slapnpop, I checked out the situations you describe.

It was the rear bolts that were missing. However, that bolt is on the very edge of the wheel where the tire meets the rim and the bolt is on the outside so if would have loosened it would have gone away from the wheel. I see no possible way for the bolt backing out to have caused the deceleration.

The front of the fender was contacting the tire, it is impossible for the rear of the fender to contact the tire as if you'd lift the front of the fender pivoting on the front bolts the wide part of the fender would contact the forks before the rear of the fender hit the tire.

As an update I took it to the dealer I purchased the bike from and they installed the new fender, and did not notice anything further wrong with the bike. Today I contacted Yamaha USA and have a case open with them. Their first step is for me to get a second opinion from another dealer stating that they rely on their dealers for the diagnosis. For now I guess I'm jumping though hoops.