I am hoping someone can explain this because I almost crashed and am not sure why…
I was going downhill, fast, but not insanely so…maybe 28-30MPH. On the way down, I kept feeling my bike twitch a bit and assumed it was a sidewind.
It would blow me an inch here the there. As I started to pick up speed it was happening more and more, then all of a sudden, and I may have braked a bit, my bike got
uncontrollably wobbly. If you where to have seen me it would have looked the way a wheel looks when it pops a spoke…but my whole bike was wobbly left to right right to left and I was lucky only in that this happened at almost the bottom of the hill and once I hit a straight section and decreased speed, I was able to gain control and continue to ride. I looked to see if I had popped a spoke but had not. I was then riding on a straight away for 5 miles and no matter how fast I got, it did not happen again. For the record, I had on a 60/90 Flo Wheel combo.
my whole bike was wobbly left to right right to left
Any ideas? Kind of freaked me out…
This will happen everyonce in a while if you get to light on the front end while a into a headwind. I have had it happen on motorcycles more when you get on the gas and it lifts the weight off the front tire a bit. On a motorcycle it is called a tank slapper becasue the handelbars can go from one side to the other real fast.
On a bike it is a wobble. I had this happen only once on my P3 and it was in Maui HI riding ~ 30 mph into a stiff head wind. I was approaching a bridge with a 100 foot drop on both sides. I just had to ride it out by slowing down and going as straight as possible without going over the side of the bridge. Scared the crap out of me and I stopped for a couple of minutes to gather myself.
Just try not to lean to far back when you are going into a headwind and you shouldn’t have the problem again.
Sounds like you got a ‘Speed Wobble’. Usually the solution to that is to relax on the bike. It is usually caused by you tensing up more and more and the bike + rider hitting a resonance frequency. The other often quoted solution is to pinch the top tube between your knees. Having said all of this 28-30 sounds pretty slow for a speed wobble, but it is entirely possible. Go practice going down the hill and trying to relax, doing it in the aerobars might exacerbate the problem due to the amount of weight over the front wheel but if it is a speed wobble the real problem is the rider + bike system.
Assuming everything on the bike in good working order (tires, inflation, wheels true, securely fastened, headset, etc) did you know the descent that you were on? Were you on the brakes? It’s easy to get all tense during an unfamiliar descent, get on the brakes and/or start developing a ‘death grip’ on the handlebars. Which can easily lead to the wobble. Don’t know your level/skill of riding/descending, so no offense, but you’ll want to be relaxed, with only a light grip on the handlebars, when descending. I recall similar experiences when I first started riding, once I loosened up they went away.
It could have been that I was going faster then 30MPH. I was trying to do just what you all suggested by getting more speed/experience on the downhills…i defintely had a death grip after a certain speed…its almost involuntary, I hit a certain speed that is beyond what I am comfortable with and I start breaking, holding on tight…I am not a new rider, been riding 3-4 years…but I have never gotten very comfortable on fast descents.
Had quite a few of those while accelerating hard out of a corner (on the track of course), front end is light and I’m applying torque to the clip-ons to point it in a direction other than straight, front while lifts off just a bit and wham… lock to lock for a few seconds before it settles out… all the while the rear end is sliding just a bit as well, so if your’ really lucky, the rear catches and you high side. Oh… that’s why they make steering dampers.
Crap… every time one of these downhills threads comes up I’m reminded how much I miss having a motorcycle and tossing it and sliding it around at the track… living on the edge a little. You haven’t really experienced 2 wheels until you’ve had a nice 2 wheel drift going mid corner, leaned off for more ground clearance, with your knee just skimming the pavement and head cranked around looking to the corner exit. Ahh… that sense of pride that you just chewed through a $300 pair of tires in about 100 miles and your peg feelers are a lot shorter than they were before.
Even more fun is when you get comfortable enough and smooth enough to be a “instructor” at a track day and can ride corers at about 80% pace, one had on the bars and looking backwards.
Cornering is like any other skill. It just takes practice and more practice until it becomes second nature.
Crap… every time one of these downhills threads comes up I’m reminded how much I miss having a motorcycle and tossing it and sliding it around at the track… living on the edge a little. You haven’t really experienced 2 wheels until you’ve had a nice 2 wheel drift going mid corner, leaned off for more ground clearance, with your knee just skimming the pavement and head cranked around looking to the corner exit. Ahh… that sense of pride that you just chewed through a $300 pair of tires in about 100 miles and your peg feelers are a lot shorter than they were before.
Yea, I know what you mean. Sold my Ducati 848 a few years back. That was a great bike that you could throw side to side in a heart beat. But the wife won the debate after my second girl was born. She said either sell the bike or buy a lot more life insurance.
I sold my last bike, a BMW R1200RT just after my daughter was born. We just weren’t going on trips anymore, so it was hard to justify a bike that was worth more than either of our cars. That thing was incredibly nimble for it’s size and I think was the perfect 2-up corner carving machine for public roads. All the electronics, heated seats,grips, luggage capacity, and accessories made touring easy.
So I bought a Trek SC7.5 with part of the proceeds and whipped my fat ass back into shape. I maxed out at 210lbs 4-1/2 years ago.
I never owned a exotic sportbike. But has a 600F4i for my first ride and a ZX9R later. I did the dual sport thing for a bit with a KLX250S. You want a speed wobble… a light push on the bars at 80mph (topped out) on that thing with skinny DOT legal dirt tires and soft suspension and it got a nice resonance going… especially with a crosswind and a passenger. But it was fun bombing down gravel backroads with a passenger with a blanket and cooler strapped to the back for a picnic lunch.
Yes that happened to me to in Kona last year. Was out for
a ride south of Kona going down hill. Went over a bridge
with guard rails, and wham bike starts shaking so bad I
thought my bike was going to fall apart. Never happened to me again.
Was on zipp wheels 808’s front and back.