What are the reasons or causes for a bike to stand up in a corner? The front brake, worn tires?
I trying to figure this out. Just recently I stood my bike up (twice) while I was in a corner. They only thing I can come up with is that when I'm coming in too hot I hit the front and rear brake. This seems to stand the bike up. What do the pros do?
I've had it happen a time or two when I go in too hot. Which is rare, since I normally poke. Engineering-wise, I have no idea what the physics are that cause the phenomenon.
Steve, yeah. Happened twice when Tim and I were out prior to the group ride. We were pushing it pretty hard... Twice I went into a corner too hot, and of course wasn't fully concentrating on what I was doing, so I had to hit the brakes (I've got to work on not taking a break when riding). Once I was just entering the corner, and the other time I was mid corner, both times leaned over. Seems that as soon as I hit that front brake, she wants to stand up.
Here you go Boney, they have had a pretty good discussion on this topic. Seems like I read a lot about it in Total Control I and II, or Twist of the Wrist, can't remember which one. All three are good books though and will definitely help your understanding of what the bike does in certain situations.
I thought that I've read before in some cycle mags that your tires can cause this? I do need a new rear, but everything is all good normally if I don't touch the brakes.
Watching the pros (granted they're pros) they're braking deep into corners, both front and rear.
I've read that our bikes do that. I've tried it on mine and it does stand up when you use the front break. I don't understand the mechanics of it, but I've seen where some have claimed that tires make a difference. Mine seemed the same with my original Dunlops and with the Michelin PR2s that I currently run.
want to know the perfect cure for bike stand-up when you brake in a turn? It's called MAN. Mix in some BALLS and you can keep that bike down even under heavy braking.
Will pushing on the handlebars help when a bike wants to stand up? Not sure if I explained it correctly but heres what I mean. Going through a right hander a bike wants to "stand up" and you push the handlebar with your right hand turning the front wheel slightly left and causing the bike to lean harder into the turn? I can ask a friend that races pro, if this gets too complicated for us...lol.
It has to do with "counter-steering". Which is a difficult concept for some to understand.
If you were to do no steering, leaning a bike does not make a bike turn. On the other hand, you can make a bike turn only by steering into a turn. But before this is done, you have to obtain the correct center of gravity (leaning). The only way to start a lean is to countersteer. If you are not leaned over enough and you are still braking too hard during the transition from counter-steer to direction-steer, your bike will straighten up and off to the gravel you go.
all bikes will stand up when hard on the front brakes, the xbs just did it a lot, even with light pressure. but i learned that the profile of the front tire and the suspension adjustment makes a big difference on our bikes.
preiviously the standing up when braking on the buell would necessitate pushing hard on the inside bar to keep the bike leaned. I know since i would compare the buell to the 7 other bikes that have graced the garage since i've had my buell.
when i changed from pilot road 1s to pilot roads 2s the amount of standing up is now more like a normal bike. i will probably run out of traction before the standing up would get too bad. trail braking is even an option now. its a night and day difference.
a little while ago i went on a long two up ride w/ a friend, i racheted up the rear preload and damping on the bike and i found that the standing up returned again. not as bad as before but it was definitely noticable. when i put the settings back i was back in business
I've got 7500 mi. on the Stradas now and the force used to counter steer has been increasing. I rarely brake in a corner, just on the entry while furiously down shifting to 2nd.
The suspension and tires can mitigate or exacerbate the effect, but the reason bikes stand up in the corners during braking or even just when you're backing off the throttle mid-turn is due to external torque (braking) being applied to a rigid body (the entire rotating assembly) resulting in a loss of angular momentum. This is a component of the Law of Conservation of Angular Momentum and it's the reason the bike doesn't just fall over when in motion.
If you are standing in the corners you need to practice more and trust your machine more or slow down as it's a reciepe for disaster. When I was out earlier this year I wussed a few corners and it nearly cost me because I didn't trust the tires I was riding I let it stand up and got in trouble. I am by no means saying you are wussing out but you may not be ready for the corner speed you were carrying.
Drumbear, it was a combo of two things: #1 Mind was not in the game, thus I wasn't sent up for the corner; #2 Speed was too high for #1. I consider myself above averages in the sense of riding/cornering. Just trying to figure out the logic behind a bike that wants to stand up. I believe I understand now, as the above link informed me.
Roy, Boney95 is part of our "Buell Group" that runs out of Hals.
Questioning seasoned racers is actually pretty darn easy for us. As we have Dan Bilansky(If you don't know WHO he is, just google his name ), Dean Hagman(used to be a learning curves instructor), And 3 others that were leading this particular ride are all current, or previously licensed road racers.
Adam is a darn good rider(he was right behind me on this ride). We normally run around a 50-60% pace to keep things safe. And leave the fast stuff for track days. I seriously doubt he was in danger of high siding...