Questions you're too embarrassed to ask

**Ixion** · 17th October 2005, 16:35

Stand (centre and side) have the same innate malevolence. They only play tricks when the chick you want to impress is watching. Hard to look macho when you're sprawled on the ground with the bike on top of you. Ultimate indignity is having to ask the chick to help get the bike off you.

**metric** · 17th October 2005, 19:15

Originally Posted by Strat

My question - what causes tank slappers?

Mine too.. am still working on getting down with the lingo - tank slappers - something happens, teh bike gets the crazy wobbles and ya legs are banging off the tank? something like that?

**2much** · 17th October 2005, 19:28

Can be a number of things, but most usually caused when accelerating hard (often in/coming out of a corner and lent over) and the front wheels unweighted then hits a bump on an angle. the wheel will flick sideways, then the physics of the bike will overcorrect that movement by flicking the other way and so on...... nuthin makes your bum pucker faster!!! Amazing how much foam one little asshole can suck up!

**Ixion** · 17th October 2005, 19:35

A "tank slapper" is when an unstable oscillation in the handlebars builds up in force and frequency until the handlebars are being banged violently from full lock to full lock with enormous force.

It is impossible to hold the bars the force slapping them from side to side is tremendous, enough in some cases to smash the lock stops off the frame and crush the fuel tank

The classic mistake is to brake or try and wrestle the bars. Almost certainly guaranteed to result in the rider being violently thrown off. The usual end of a tank slapper is a crash. The only possible way to deal with a full blown tank slapper is to accelerate gently. Which is counter intuitive and takes a lot of courage. Even then it may not work . Pray. And throw yourself on the mercy of the Biker Gods.

What causes it? Not really known, it is steering instabilty that sets up a feedback mechanism with the natural harmonic frequency of the frame (or something like that). Usually it is set off by a bump when cornering or some such, but some bikes it can just happen for no discernable reason.

It is the most frightening thing that can happen to a rider, IMHO

**avgas** · 17th October 2005, 19:55

2 stroke is fun
4 stroke is fun
2 stroke smell nice
2 stroke like havn a turbo
Do it before its illegal!

**SlowHand** · 17th October 2005, 20:13

here's my 2nd - how do you accelerate if the bastards slappin the tank like a pimp in a ghetto?

**Ixion** · 17th October 2005, 20:16

Originally Posted by Strat

here's my 2nd - how do you accelerate if the bastards slappin the tank like a pimp in a ghetto?

With very great difficulty. Which is why you usually end up getting tossed off. hang on like grim death (unfortunate simile) and try to grab some throttle. Probably won't work, but. But anything else is worse.

**2much** · 17th October 2005, 20:20

Pray you get a bit of a warning before it gets to that stage and get on the gas asap

**Motu** · 17th October 2005, 22:26

Most often you are accelerating out of a turn,so you can put some power on...but yeah,counter intuative,like a lot of things to do with bikes (try turning on a wall like us trials riders do,or for me,used to - approach wall,big handfull of throttle and pull the front wheel up,shit your pants and marvel at your skill at the same time) I get wobbles on cresting turns,the bike lands with the front wheel out of line as I land countersteering,scary shit because it always happens at speed (120kph is fast to me!) Biggest wobbles are in sand,you can get up to a good speed on the beach,and if you get into a speed wobble they are really big powerful tankslappers - the sand building up behind the wheel slams it over,powersteering with sand build up in front of the wheel....there is just no way to stop it,just ride it to a standstill.I was on the beach 3 weeks ago and got to learn scary things from the past....

**N4CR** · 17th October 2005, 22:32

Originally Posted by Motu

False neutrals only happen when girls are watching - if you see a nice looking chick you want to impress....don't change gear!

But if you redline it, it scares them away

Ya gotta look fast you know!

Just can't win eh

fucking neutral.. just abolish it

**M1CRO:Me** · 17th October 2005, 22:52

Originally Posted by Strat

here's my 2nd - how do you accelerate if the bastards slappin the tank like a pimp in a ghetto?

I have a different opinion on resolving this. Quite a few years ago (maybe 17? and yes I was riding then), some bikes were prone to tank slapping. These were due to instability as a result of wide range of things which I wont get into but I tend to agree with most of Ixion comments.

Generally, these Tank slappers were as a result of "speed" and were sometimes known as the "speed wobbles". I am not sure if this is exactly what you were getting into, but at the very least you can add it to the list of useless trivial things that you now know

Anyway, to resolve this, you need to lower your centre of gravity!! The best and easiest way to do this is to lean over your tank and slowly deaccelerate. Of couse, building up your speed once your over the tank, will only result in another tank slapper. If this happens, you have no way your lowering your centre of gravity, and you will end up being thrown off..

I have only once experienced this and it happened to be on a XJ750 and I was doing around 150km on a country road.

My 2c worth

**Ixion** · 17th October 2005, 23:07

Video of a slapper

**M1CRO:Me** · 17th October 2005, 23:10

Nice video

Edit - Did you notice that the speed wobble starts, then;
left foot comes off the pegs.. result: wobble gets worse..
right leg comes off... result:. even worser (sic)!

Still stick to my advice that if he leant down over the tank at the start of the wobble the bike would still be in one piece

**2much** · 17th October 2005, 23:39

That's damn scary, agree with Ixion, that's probably the worst thing to have happen on a bike...... or dropping it while showing off in front of some hot chick!