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I never knew what a tank slapper was...
Posted: Sat Jan 28, 2006 11:02 am
by Shiv
until I watched a few videos with them in them.
I never knew your bike wobbled around so much in a tankslapper. I thought what happend was you hit the brakes too hard and slapped your tank with your knees/body.
So the obvious question from a noob rider: How do you get out of a tank slapper?
My guess would be the same way you get out of a spin in a car (minus the brake), go with the tank slap (where the bike wants to go) and try to get out of it that way.
Not Easy
Posted: Sat Jan 28, 2006 11:55 am
by Runswalking
I was lucky enough to not crash by getting on the gas hard. The drive straightened the bike out and I only had to stop and clean my pants! HA HA!
I have read theories that the front tire loses it fiction contact point and then starts to oscillate side to side. This causes the rear to freak out and it wants to see what the front is doing so it tries to come around and to get a better look. HEHE! If you can get the back to do something quickly and it will push you into a straight forward line. The front will stablize and quit dancing. Application of power is all I've ever read or heard about to stop it. Maybe someone else has?
After you've been spitoff once or twice you have time to think about whats happened. Rolling on throttle goes against every sense you feel at that moment. Look where you want to go and nail it. I learned at a track day event. Three TS's coming out of the same curve with two spitoffs. I've never experienced a TS on the road. Ride safe.
Posted: Sat Jan 28, 2006 12:03 pm
by nike_soccer
A little bit of gas and look at the horizon.
Re: I never knew what a tank slapper was...
Posted: Sat Jan 28, 2006 12:11 pm
by 2wheel
Shiv wrote:
So the obvious question from a noob rider: How do you get out of a tank slapper?
Throttle, man Throttle!
Posted: Sat Jan 28, 2006 9:19 pm
by BuzZz
Tankslappers or headshake can be caused by either hard acceleration or hard braking, depending on the bike and the road conditions..... if your bike is prone to it, you'll soon know which one it is.
You will never 'compensate' for the bar's movement, in fact if you try, you will make it worse. Loosen your deathgrip(cause you
will have one) and let the bike straighten itself out.
If your bike shakes on brakes, usually backing off the binders a bit will help, but your probably on the brakes that hard for a reason, so less brake might not be an option.
If it wobbles on the throttle, most of the time your best bet it to keep it on and ride it out..... grip the tank with your knees, relax your grip on the bars and enjoy the ride. Most likely to happen when tearing out of a corner and the front end is light from hard acceleration.
I've had bikes that will calm down if you back off the throttle during headshake, but I've had more bikes that shake harder if you close the throttle.....
And of course, none of this is really a problem until your experienced enough to be nailing corner exits that hard. By then, you should be skilled enough for it to be an experience, not an incident.

Posted: Sat Jan 28, 2006 9:33 pm
by Shiv
So is that why you see a lot of tankslappers after wheelies and what not? They're pinning the throttle to get the revs up and keep the front end light and thus the bike oscillates and then when they set it down tehy're in a tankslapper?
Cause I've seen it in racing videos (coming out of a corner like you said) and in 'watch this idiot crash' videos and most of the time, it involves a wheelie.
Posted: Sun Jan 29, 2006 4:40 am
by SuperRookie
When in doubt, gas it...

Posted: Sun Jan 29, 2006 1:18 pm
by dr_bar
SuperRookie wrote:When in doubt, gas it...

Are you talking about throttle action or what you want to do to squids on gixxers... ???

Head shaking
Posted: Tue Jan 31, 2006 4:58 pm
by Runswalking
Hey Buzzz, good write up there. A point of clarification for me; I have always thought of head shaking as being an action due to or attributed with braking. For me, usually just before releasing the brakes prior to apex or there abouts. I think of it as that naked line just before I loose traction. On the newer sport bikes I have never felt this in straight line hard braking. Headshaking can be due to loose or worn steering head bearings too, have you ever noticed that feeling? Not quite a full on head shake just that feeling of edginess, letting you know that you're about at the limit with that setup.
Tank slapping I think of as an action seen in accellerating, usually just after the apex of a curve in my experience. When a smooth transistion is not made. Light frt or slightly crossed or stuff on the track ect..
I'm just running thru some thoughts here, I've only dicussed this a couple of times with riders who have the skill level to have felt it and not crashed. JMO
Posted: Tue Jan 31, 2006 5:24 pm
by BuzZz
I find dirtbikes more apt to shake hard on heavy braking than streetbikes, but my old RD's would do it something fierce if there was any kind of rippleing in the pavement. I always tend to subconciously expect it more on braking over accel, too...... but I've had both.
Bikes with more sporty(steep) head angles seem more prone to shaking on hard accel. Wheel misalignment due to cornering combined with pavement irregularities and a light front wheel all seem to gang up and induce a wobble in 'twitchy' bikes. But I've even managed to make my old FJ wobble a bit in some more aggressive corners, and I wasn't really pushing it that much..... I'm hopeing my new front tire solves that.
Loose head bearings can definately lead to funny front end action. Not only headshake, but wheel chatter in corners, clunks and rattles anytime and a general 'ratty' feeling to an otherwise solid bike. Tight head or notchy bearings can be a PIA too, making it hard to impossible to maintain a straight line and a wandering bike. It's possible tight bearings could lead to wobble too, but I've never experimented with this..... not in a big hurry too, either....
