I thought about that too, but I would expect to see that rear tire looking like it’s about to fall off the rim and too chances are pretty low on a tube tire to have sudden rapid decompression, usually you feel it getting loose in the rear…What you describe regarding a cone drill, sounds like lateral oscillations, similar to an instant tire failure. Did one of your tires blow? It may be just the angle, but is the rear tire bead broken from the rim in the photo?
So I took my 2019 Africa twin adventure sport to the shop and all they did was change the fuel filter they didn't flush out the tank or the fuel system and I ended up wrecking a hundred yards from my house. Shop is only 10 minutes away. I was following behind a car when all of a sudden the bike went crazy and slammed me down. Going 3rd gear around 48-50mph. Now I'm not blaming the shop just wondering what y'all think? I've got 50 sutures in my right arm. The bike was off when I went to get the key. The best way I can describe is the bike slung back and forth like it was going through a cone drill before slamming me.. Traction control on and ABS. Can anyone guess what happened?￼￼￼￼￼
@treydizzle45What you describe regarding a cone drill, sounds like lateral oscillations, similar to an instant tire failure. Did one of your tires blow? It may be just the angle, but is the rear tire bead broken from the rim in the photo?
You dont have a fork brace.... it's a game changer on and off road on brpNo.
The cure is to get through the condition that is causing the problem. If you're either accelerating or decelerating, you can can get through it if you apply more of what you're doing, assuming you're not already at the limits of your gassing or braking.
I've done it on sport bikes at street speeds - decel and accel - as slow as 35mph, sportbikes at track speeds - decel and accel. GoldWings at steady, elevated highway speeds by taking a hand off the bars - started as a slow weave, increasingly progressive, would've ended badly but stopped immediately when I put the other "phase" of the two-handed steering damper back in place.
EVERY bike I've ever ridden has a couple/few zones where this phenomenon can present itself so I assume it's not bike specific. That you inferred differing sizes of wheels being a factor does change the conditions in which this may occur, and I've done it on an XR650L, as well...not one I'd like to repeat. The huge wallowing due to long suspension strokes exacerbates the situation.
Downhill turns, uphill turns, one-handed riding at that certain steady speed, flat leisurely accelerating/decelerating, it doesn't really matter. What matters is the steering/suspension geometry, including tire profiles and the bike's attitude, in which those dynamic components become effected. There are likely a near infinite number of combinations that can induce a tankslapper, just as there are a near infinite number of combinations that can eliminate them. Once in a while, you're likely to find yourself in that threshold and get caught out. Many, many more times you'll cross the threshold and not even know it cuz you've continued on through it before it could take hold. You won't know what conditions will set it off until you experience them presenting themselves...and then you learn to eliminate factors of those conditions through varying your riding technique(s) or altering your bike's settings. Altering settings can be good or bad. Depending on which direction you go, you could eliminate the occurrence in that one situation only to promote it in another.
As to your bicycle wheel example, the outside forces would be a motorcycle's rear wheel, the bike's attitude, the steering angle, the suspension geometry and settings, the tire, the wheels' balance, the pitch/camber and surface of the road, the rider's style/technique and the rate of progress. Pick one, or more, to either induce or eliminate the occurrence.