They're the result of harmonics, for lack of a better word. A small wobble at the front (Grabing too much of on handle or the other, bumps, loading/unloading the front wheel at the wrong moment, etc) continues to increase in severity as the bike wobbles from side to side.

It's sort of the opposite of a pendulum. If you let it swing from side to side, it loses momentum each swing, until eventually stopping. A bike will increase the momentum due to weight and the gyroscopic effect of the wheels spinning, causing each succesive 'wobble' to be a bit stronger than the previous one.

 

It's not just enough to say that the rider contributes to the slap. It seems that in most cases the rider actually causes the slap.

From most of the stuff I'm reading, this occurs when the front end lightens up and the front tire comes down "kinked". (I don't know whether that's a legit term, I saw a dude on 600rrnet use it and it seems logical) So whether you hit a reasonable dip and the front end lightens up unexpectedly and the rider's weight on the bars gets the front tire wobbly or you come out of a turn hard on the throttle and lift the front end and the front comes down sightly off or you just accelerate really fast so that the front end comes up and you bring it down slightly off.

It seems that rider error contributes a lot to tank slappers, and the over-correction of the rider to try and save it seems to further the problem.

 

that's right, unless something breaks on the bike, causing the wiggle or instability, it's usually the rider trying to steer the bars, upsetting the bike with the front brake, or not having the front tire in the right position when it gets light and comes back down. A bike set of in a straight line or ridden correctly through a turn will almost always keep itself moving straight ahead, and balanced as long as it maintains the speed necessary to keep it upright.

 

totaly depends on what speed and gear your in at the time of the slapper, sometimes they fall away before you even have time to react, ive had sore knees on several occasions, but the times i have had to react ive let go of the throttle and added some rear brake (gently) this i think has saved me afew times.. ive never heared of any one power thrugh a true tank slap

speed wobbles are different you can easily power through them provided your on good road surface, mild to moderate ones make you feel alive, any more its best just to ease off or keep on the same throttle and dont adjust,

then theres road skip, where the road surface is very uneven bouncing the front end while its lightened up coming back down slightly off center, easing off works well

best way, if it really bothers you is fit a damper, they work wonders and save you and your pride'n'joy from the fall of doom

above all, pay attension to the road surface, personally i enjoy a small amout of wobble, and have a damper on lighter setting

 

Relax loosen your grip(but don't let go)(floppy arms) move your weight back more throttle.
I'm usually laughing at this as I grew up on slabside gixers.

 

I only get wobble when its pissing down rain and Im being a little harsh on the throttle. I know when its coming and kinda like the small wobbling sensation.

I also enjoy breaking hard in the wet and the feeling of the back end wondering. Not sure what exactly is going on but it feels good.

Never had any tank slapping in the dry.

 

I dont think there is a difference(opinion).
I was accelerating from a stop light with one hand on throttle and other on my knee with a passenger on the back when the road changed to a stretch of crappy @ss asphalt patch job from road construction when the bars got away from me violently slapping left right left right. I managed to grab a hold of the bar with my left hand(should have already had two hand on the bars, duh) and it straightened out. It all happened so quick but i thought for sure we were both going down.

 

i have had it happen to me twice. both times on bad roads with a whole bunch of little bumps right in a row. the road looked just like a perfect wave. up, down, up, down, up, down, up...like a sine wave. and the first time i had only one hand on the throttle, the second time i was adjusting my glove so i had no hands on the bars at all. each time it slapped about 4 times then quit.

 

Seems you guys have it pretty much covered. If you land a wheelie screwy and it causes a slapper the quickest way to stop it is give it gas and neutral steering input (i.e. very light on the bars). If you have a high speed wobble then maintain throttle and relax the death grip on the bars ... gradually decrease throttle. NEVER hit the front brakes!!! Rear brake is semi o.k. for a high speed wobble but not for a true slapper.

Once you get it settled down think about investing in a good damper ...

Great topic

 

One of the local shops in my area had invited an instructor with a lot of experience to talk about cornering, steering, braking and etc. It was very interesting I have to admit.

During our discussion about braking, he said that the rear brake is useful only when it's wet and when you get the tank slapper. Just tap the rear brake to stabilize the bike. I have never had such situation, but I'd definitely do what he said if I ever get one, since there is not so much time to think any ways.