What to do if a tankslapper occurs?

Stealth · 03-20-2006, 10:50 PM

The reason they say you ought not to try and restrain a slapper is this;
You are anchored to the bike well back from the head stem and so by try to restrain a slapper you transfer the movement to the rest of the bike making it worse. The damper does it but is anchored near the head stem so doesn't have the leverage to transfer the force to the rest of the bike. That's the theory anyway....

anabatic · 03-21-2006, 1:16 AM

a horrible wheelie last year ended up in tank slap, letting off the throttle and clutch worked but took about 4 to 5 seconds to come out, only 65 mph not anywhere near what people do on the track but scary by far letting off it the best that can be done, good advice by all.....

tnarinen · 03-21-2006, 7:18 AM

Quote:

Originally Posted by luvtolean

It should, I'm pretty sure that rider died. And he probably did have a damper.

The way I heard the story was that he lost a couple of fingers and retired from racing, but I'm not 100% sure about it.

Lot's of people call all headshaking tankslappers, I've had a pile of headshakes with both my 954 (I did about 10 trackdays on 954 without damper as Ohlins was sold out early 2002, lot's of headshaking) and my 1000RR, but never a real tankslapper. 954 was quite headshake-prone in our bumby winter-damaged tracks and there were couple of places where I got shakes on almost every lap. I found that "soft grip" was best the best way get rid of them fast.

The worst headshake ever I got was switching from 5th to 6th in an airfield track, doing about 260 km/h (indicated in a stock-geared 954) in a mile-long straight and hitting a big bump at the same time. I had finally installed the Ohlins damper a couple of days before, this was early august 2002, and Ohlins + soft grip took care of that quite nicely.

While I believe one can muscle out of slappers in a dirtbike where speed and weight are much smaller, but with a sportbike and in high-speed, I dunno. I know I'll never have enough muscle for that so I'll do what has worked me best.

MetallicCarrot · 03-24-2006, 9:32 PM

Quote:

Originally Posted by tnarinen

Lot's of people call all headshaking tankslappers

In a severe tankslapper, you aren't going to hit the rear brake, because your feet are going to be off the pegs, ala the tank slapper video above.

You also aren't going to save it by going WOT. I've done it, it goes:

waaaa, *wiggle wiggle wiggle* waaaaaaaaaa *wiggle wiggle wiggle*
WAAAAAAAAAAAA *wiggle wiggle wiggle* WAAAAAAAAA *wiggle wiggle wiggle wiggle* CRASH. Ask me how I know.

If you get a true tankslapper, the kind that makes black-mark-half-moons 10 feet apart on the asphalt, you aren't going to do anything but pray. If the bike comes back under control, either A) the slapper didn't escalate to unmanagable proportions, ie: the bike corrected itself, or B) you got lucky. I had a friend of mine have a tankslapper in front of me, with another friend riding right beside me. He said he hit the rear brake, but my buddy beside me and I could see that his feet were clearly way off the pegs. He just had enough road for the bike to straighten itself out.

9uno9 · 03-27-2006, 7:29 AM

how tight your headset/neck bearings/whatever they are called has a bit of impact on how easy it is to get a slapper, i ride with mine tightened down cause i dont like dampers, at all, and ive logged over 20k on a several blades, only got one once cause i was being STUPID and half asleep, otherwise, never, and i ride my bike to top speed, setting up your suspension properly and tightening your headset on a blade will eliminate most need for a damper unless you have to have that extra 1/3 second faster exit speed

tnarinen · 03-27-2006, 10:25 AM

Quote:

Originally Posted by 9uno9

how tight your headset/neck bearings/whatever they are called has a bit of impact on how easy it is to get a slapper, i ride with mine tightened down cause i dont like dampers, at all, and ive logged over 20k on a several blades, only got one once cause i was being STUPID and half asleep, otherwise, never, and i ride my bike to top speed, setting up your suspension properly and tightening your headset on a blade will eliminate most need for a damper unless you have to have that extra 1/3 second faster exit speed

Exactly how does lap time/speed correlate to headshake likelyhood? I got most headshakes from my 954 when I was still dog slow, not that I'm a fast one now. You need to be no Rossi the accelerate enough to make the front light and hit a bad spot.

Will having the suspension perfectly set up help? Yes, but you can get a bad headshake with perfectly set up all-Ohlins bike and in most of those cases a damper will help.

Not like dampers? I don't exactly like wearing helmet, but for some reason I do keep one and yes, I consider damper as essential for sportbiking as helmet, both belong to the list of items I don't ride without. I do have a WP factory built front suspension and WP rear shock in my 1000RR and I still see steering damper in action every now and them.

9uno9 · 03-27-2006, 11:05 AM

you know it all bud, what can i say

except that i buy and sell 954s, 929s, 1000rrs, and ive ridden a bunch of them, aside from my own personal blades, and alot of it has to do with rider too, its not all that hard to induce a tankslapper if you want to, i grew up riding bmx and still do, front wheel sensitivity is a bigger issue on bmx than on sportbikes, so maybe im just overly sensitive to it compared to other people, i dunno. im just talking about how it works for me, i guess you know everything though

abtech · 03-27-2006, 11:14 AM

Quote:

Originally Posted by 9uno9

how tight your headset/neck bearings/whatever they are called has a bit of impact on how easy it is to get a slapper, i ride with mine tightened down cause i dont like dampers, at all, and ive logged over 20k on a several blades, only got one once cause i was being STUPID and half asleep, otherwise, never, and i ride my bike to top speed, setting up your suspension properly and tightening your headset on a blade will eliminate most need for a damper unless you have to have that extra 1/3 second faster exit speed

What is it about a steering damper that you don't like?

I find it somewhat interesting that most race organizations require them, yet your 20K miles on several Blades have proven to you that they are unnecessary.

luvtolean · 03-27-2006, 12:33 PM

Quote:

Originally Posted by HRC NICK 11

.Largest one ever was most of the front straight at Grattan,

Hit the bumps hard on the gas in the last turn?

I was following a guy during a race there and he was holding me up. The red mist descended and I decided I was going to outdrive him no matter what...and I did, for at least several yards, but damn, that tankslapper was memorable.

Luckily lots of room before the grass to get it back under control.

Red Rider · 03-27-2006, 1:38 PM

Quote:

Originally Posted by luvtolean

Hit the bumps hard on the gas in the last turn?

I was following a guy during a race there and he was holding me up. The red mist descended and I decided I was going to outdrive him no matter what...and I did, for at least several yards, but damn, that tankslapper was memorable.

Luckily lots of room before the grass to get it back under control.

Some guy on a Gix1K got into a big slapper coming onto the straight at Grattan last year, and he DID run out of room. Fortunately he was already off the bike as it shot up the hillside into the armco...and showered the pits with parts.