Group Riding Accident Video-Bob's Final Ruling

[caper]

What Yellow jacket and Dabull said :)

[garyo4]

I'd have to say it's more like the engine seized, locking the rear wheel up. Even as the bike slides past us towards the right of the screen (without the rider) there is still smoke coming off the rear wheel indicating that it is still locked up.

[1badbagger]

I watched it several times. Perhaps a bike malfunction can be to blame for the guy on the first bike. Maybe the belt snapped and wrapped around the rear axel of the HD. I've heard stories of chains and belts doing that. Maybe a rear blow out? If he did just lock up the rear he made the mistake of getting out of it. The rule I've always known is: Once the rear starts to slide, let 'er slide. Otherwise you run the risk of high siding it. The guy behind him I think just went into panic mode and bailed. All the more reason to go out to a parking lot and practice your emergency avoidance and swerving techniques. Too bad for both guys though. Bummer. Hope no one was hurt.

[bobhamlin]

After reviewing all the insightful -- err, umm -- insights and lacking direct input from the riders directly involved in this tumble, the following points are pertinent:
1) The back wheel locked up -- as evidenced by the puff of smoke that immediately preceeded the loss of control.
2) The back wheel did not stay locked--as evidenced by the lack of continuing smoke and that the bike seemed to be rolling well for an extended time.
3) There was no catastrophic failure that resulted in a seizure of the back wheel -- for the same reasons as in #2.
4) Something caused the driver to extend his left leg, seemingly in a futile attempt to maintain balance.

My interpretation of the probable cause? The driver attempted an upshift but inadvertantly downshifted. My rationale:

1) I have performed such a dimwitted action. (If I -- as the motorcycle stud I perceive myself to be ;)-- can do it, anyone can)
2) He is a solo rider. An abrupt downshift could lock the back wheel since there is no passenger placing extra weight over that wheel.
3) The key is the abrupt leg action. A sudden, unexpectedly locked back wheel would subject the driver to inertial forces for which he is not prepared. When downshifting, the only contact he'd have with the platform is a small portion of his heel. His leg, relatively relaxed in its driving position, would easily lose contact with the platform. Reflex would then seek balance, hence the touchdown.

Why I discount the brake's involvement: No one saw anything that would initiate a panic stop. He seems surprised. If the brake miraculoulsy seized, I would expect the smoke to continue and for him to seek balance a little later in the sequence.

The second rider? Panic braking.

[biscuitsngravy]

Whatever made him put his foot down caused it to drag back and under the bike, pulling him off onto the pavement. BnG

[1badbagger]

After riding cruisers for many years, most of them with more hp and torque, than the Nomad, I have never locked up my back wheel with an upshift. I used to do it all the time on dirt bikes though. Still confused as to how that's done.

[flightdoc]

I wonder if the group was starting to pull over to "collect" the person filming. Maybe once the lead riders got past the camera they started to brake (hard brake) and pull over so the person filming could load up and then get back to riding. Maybe the guy that fell first wasn't paying attention...looked up and panicked...put his foot down like a cyclist might do?? The second guy went down immediately...he definitely doesn't know what to do in a 'avoid a collision" situation. My 2 cents.

[clayton]

Yea it looks as if something locked up and the guy freaked, lost control and possibly the 2nd guy might have clipped the 1st bike or the 2nd rider just locked it up and lost control as well.
But the 2nd biker was not close enouph to cause the accident.
Dam! 1st dude got smacked by by the second bike...
I hope they turned out ok...
Bummer

[Top Cat]

Yeah the second bike hit the first guy down as it went by. No doubt about that.
I have heard of chains breaking and locking up the back wheel but not belts. I heard belts tend to just roll off when they break.

[flightdoc]

what leads any of you tothink it was equipment malfunction??

[Top Cat]

Originally Posted by flightdoc

what leads any of you to think it was equipment malfunction??

I think he was riding a Harley. ;)

[bobhamlin]

Originally Posted by flightdoc

what leads any of you tothink it was equipment malfunction??

The locked back wheel (smoke) seems to take him by surprise.

[flightdoc]

I have my doubts. I'd be willing to bet that nowadays equipment failure happens VERY seldom. I've owned bikes in the past that I let develop rusty chains and hardly every changed or even checked the oil to name a couple of things and never had issues with them. i've never had a bike break down due to catastrophic failure and have never know anyone that has and like most of you have been riding for a very long time. I think the rear wheel locked because the driver locked it...I think he panicked for some reason. My 2 cents.

vin

[glwilson]

[quote=Top Cat (TC) ]

Originally Posted by "flightdoc ":aa8y3mab

what leads any of you to think it was equipment malfunction??

I think he was riding a Harley. ;) [/quote:aa8y3mab]

Hey TC!!! Easy there now... be careful... I am a bit sensitive...

[unwind2]

Gotta say it...what a strange scream by the person filming...sounded like a bird. Just had to say :-/