DriZay said:
was it wind...too hard of a landing for the speed...handlebars crooked...
I've been trying to disect this vid because I don't want it to happen to me. I can't say, with certainty, exactly what caused it so I can't offer a remedy.
I can offer a couple of observations, though.
I've never noticed me bike doing the "shimmy" during:
1. power wheelies
2. sit-down wheelies
3. stand-ups when both my feet are on the pegs
It seems to happen only when at or very near the balance point, but, even at , near, or beyond the balance point, it has only happened to me doing "knee on the seat" wheelies.
Apparently, then, balance is a major contributing factor.
One way I've found to reduce the phenomena during "knee on the seat" wheelies is to relax my upper body. It seems that if my grip & upper body is tense, it increases the effect (similar to tankslappers, in that when you tense up & grip the bars very tightly, you contribute to the intensity of the slapper), but if I'm "loose", my body tends to "absorb" & diminish the shimmy.
Another thing I do when I first detect the shimmy is to let the front down. I don't always go all the way down because sometimes the shimmy stops when the front wheel is a few feet off the ground. When the shimmy stops before the wheel hits the ground, I gas it & bring it back up. I may have to yoyo like this 2 or 3 times, but usually once does the trick.
A friend of mine (who has done a 24-1/2 mile wheelie) suggests just riding the wheelie out & the shimmy will dissipate on its own. Well, that doesn't always work. One time I was doing a "knee on the seat" wheelie & the shimmy began. I was riding it out when I hit big dip in the road. The instant I hit the dip, the shimmy got so severe I started preparing myself to slide down the highway. You know, when get to the point where you are mentally prepared to wreck, you usually do & I was at that point. But, the strangest thing happened. I let off the gas so the front end would come down, but when the front started coming down, I gave it the gas so that the front end would not "slam" down & make things worse.
Well, due to luck, technique, or my guardian angel (I'm leaning towards guardian angel) the shimmy dissipated and the front end landed softly. After that, I took a few deep breaths, laughed (because I was fine), then gave thanks to God:thumbup