Author Topic: What's a tankslapper, and how do I avoid or get through one?  (Read 7649 times)

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Offline Stev-o

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Offline MCRider

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Re: What's a tankslapper, and how do I avoid or get through one?
« Reply #2 on: January 08, 2011, 08:36:47 am »
That is a very good discussion of the situation, as it applies to race track circumstances as well as moderate to aggressive street riding. There is another situation as well.

That is, even in a straight line, if the front suspension is bottomed out, like when hitting a hole, or high bump, the energy is initially absorbed by the suspension. But if that's not enough, and the suspension bottoms the energy will then transfer into the steering creating a violent side to side motion, tank slapper. The bars will be ripped from the riders hands and you will likely go down.

All the fixes in the article apply, but more importantly I think others should be considered. That is, don't reduce the suspension travel, don't lower the front end to the point where the fender will contact the lower tree, and upgrade the fork to a cartridge emulator if possible. Our old forks are pretty much linear in their absorption. Emulators make the damping much more progressive, absorbing more energy as the forks compress, resisting bottoming.

Virtually all modern bikes have the cartridge style forks, so the bottoming tankslapper is not so common.

My explanation may be very amateurish and not technically correct. But i know from first hand knowledge from where I speak. And it can definitely be lethal.
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Offline scottly

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Re: What's a tankslapper, and how do I avoid or get through one?
« Reply #3 on: January 08, 2011, 08:50:27 pm »
Perhaps this thread should be re-titled simply "how to survive a tankslapper"?
I agree with the part in the article about keeping pressure on the foot-pegs; I learned on dirt-bikes just how important that can be in controlling the bike, especially in an aggressive riding situation.

My definition of a tank-slapper: The scariest 1.5 seconds you will ever experience on a motorcycle, that does not involve another motor vehicle, animal, or 30 foot drop-off.
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Offline BLUE71TURBO

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Re: What's a tankslapper, and how do I avoid or get through one?
« Reply #4 on: January 08, 2011, 10:08:06 pm »
 I thought  ?'s belonged somewhere else ?
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Offline scottly

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Re: What's a tankslapper, and how do I avoid or get through one?
« Reply #5 on: January 08, 2011, 10:17:23 pm »
I wondered about the "question" being posted in this section, until I read the referenced page, in the linked magazine article. This belongs here, as it is a tip about motorcycle survival skills. 
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Offline Nikkisixx

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Re: What's a tankslapper, and how do I avoid or get through one?
« Reply #6 on: January 09, 2011, 05:09:48 am »
Pretty good article, but you could just go straight to the source and hear it from the horses mouth:

http://www.superbikeschool.com/keiths-corner/

Keith Code's Twist of the Wrist 2 DVD is awesome (avoid the snooze fest of his first video).  His book is stuffed full of 411.  Reading and watching that stuff will help you get the chicken strips off your tires, and better on the street.
It is a proven fact that modifying a SOHC Honda in any way will bring on the apocalypse.

Offline Retro Rocket

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Re: What's a tankslapper, and how do I avoid or get through one?
« Reply #7 on: January 09, 2011, 04:08:00 pm »
If you fear tank slappers,and i had some good ones on K series Honda's,just use a steering damper, on the street i have never had a tank slapper on any bike fitted with a damper...... ;)

Mick
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