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I've heard the "tankslapper" described on this forum, and some folks advocate a steering stabilizer to prevent this crash causing issue. I have a question to any of you that may have experienced a "tank slapper"--what did the edge of it before it happened feel like? I have a murphs forkbrace on the way because of my stroms skittish front end @ speed, and think I've came damn near a "tank slapper" trying to pin the throttle on windy days. What did it feel like right before the tank slapper happened for you?
 

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JW, I've never had a tank slapper but I think a half second before a Tank Slapper, the steering probably feels normal. They come on suddenly and there's usually nothing that can be done. They either throw you down or they don't and it seems to depend on how bad the situation is, not on how good the rider is.

I've heard lots of riders describe slappers on street bikes. One said he tried to save it by using his hands as a steering damper, releasing the bars and regripping them lightly. He didn't think it made a difference.

Powerful bikes accellerating over bumpy surfaces is a common cause. Sometimes high speeds can be sensitive to instabilities, bumps probably starting a reaction. Hitting big bumps like when riding in the dirt can cause a slapper. One big deal is keeping your balance because you don't want to fall off if the bike is going to right itself, but if the bike goes into an uncontrollable wobble, well, that's a nightmare and there's not much a rider can do.

Bottom line, you can put a steering damper on a bike and prevent slappers but trying to manage one is probably nearly 100% futile. Stroms aren't one of the more slapper prone bikes but since bumps can cause slappers they can happen to any bike I guess.
 

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Here is a relatively "famous" video of a tankslapper

http://youtube.com/watch?v=LZ1srcQMa_0

The bike develops an oscillation due to an event that upsets the suspension and straight line stability. It can be a bump, it can be extreme accelaration, it can be high speed with poor areodynamics on a heavily laden bike, it can be a sudden loss of traction of one end of the bike, it can be setting down hard from a wheelie, (taking your hands off the wheel while decelarating?), usually it is a combination of things. The only pivot spot for the bike to oscillate around is the front steering. In the video above you are watching a professional, someone who makes a living riding at 9/10ths+. He is helpless to get the bike back under control, he is not the one moving the front wheel side to side. Watch closesly and the point of the triple tree is moving in a straight line, it's the rest of the bike that is all over the road.

It is possible to ride out a tankslapper, the bike really wants to go straight, the oscillation will eventually end. You will probably however go down, not because of your riding skill but because physics and traction are at odds in the middle of the event. The bike is moving around the pivot point, the front tire is doing the opposite of the rear trying to work itself straight, traction of the tires now work against you and can actually make the oscillation worse.

The steering stabilizer basically eliminates the pivot point at speed, if an oscillation starts it dampens it.. like a shock absorber attached to both sides of your handlebars.

What you experienced was probably not a tankslapper unless you were scared shitless, crying, seriously considering never riding again and perhaps lost control of your bowels. You probably lightened up the front end considerably by pinning the throttle and the wind moved the bike from one side to the other. The strom is relatively light and tall and the wind affects it more than smaller heavier bikes.

I encourage you to slowly explore your limits and your bike limits, invest in quality riding gear, take a msf course, do not take the bike to the strip bar and chill out on the bike, enjoy it and ride it, learn!
 

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This youtube was listed after the one BB listed I think it shows the begining tank slapper in a straight line - from the cockpit - so it's pretty telling.

http://www.youtube.com/watch?v=5xLHOWojaOo&NR=1
That is not a tankslapper, it is "headshake". That's perfectly normal on those bikes. That is what a steering damper does to a possible tankslapper on a literbike. I may have had that same model bike and a steering damper, never went to a track and rode like that though. I've felt the headshake. All you had to do was accelerate hard over bumps and there you go.

Multiply that by 200 times and you have a tankslapper .
 

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I had a pretty good tank slapper on my 1400 Intruder several years ago. I was traveling down a gravel road on my way home from work, while I was at work they added 3" of golf ball sized gravel to the road, I hit that patch at 45 MPH. I was able to make it out without going down. Maybe not technically a tank slapper, but the front tire was not going where the handle bars were pointed.....
 

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I did a classic tankslapper on a Yamaha RZ350 back in 1987. When all was said and done and I picked up the pieces the gas tank was as wide as the gas cap. The cap was all that prevented both sides of the tank from touching each other. It snapped both steering stops off and highsided me at about 75MPH. Trust me, if you have real tank slapper, you'll be the first to know and you'll never forget it. Ahhh..how I long for the days of my misspent youth. By the way, I just bought another RZ...stay tuned...:D

SS
 

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From the tell tale sign to the event are going to be too short for you to do anything about it. If your pushing the limits of the bike, the road, or yourself these are all a good indicator that you may be on your way to one of those. I am sure that at much over 100 MPH and your pushing it. The way the fairing is set up on these bikes it makes the front light with the wind resistance. At that point all it will take is a small dip or bump and you can be off to the races. That is why you hear it talked about most when these bikes are heavy with gear on the back.
 

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I had a tankslapper on my previous bike (KLR) at around 80-85mph. I managed to ride through it but I was very lucky. I physically shock for about 10 minutes afterwards. It started as a slight wobble then progressed to a full on wobble and I could barely hang on to the bars. I tried to gradually slowing down but it continued to all the way down to around 40 mph then stopped. I thinks what caused my tankslapper was a heavy load on the rear, not enough rear preload and to high of a speed for the bike. My new wee now has a Scott's steering dampner. I may have cost my $400 buck but once you experience a tankslapper $400 seem like a bargain. I would never ride another bike at 50+mph without a steering stabilizer.

Ask Greywolf why he uses a steering stabilizer. His story and my experience convinced me to spend the money.
 

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If I had a Scotts installed in June, 2006, I'd have 37 fewer screws in my body, 2 working shoulders, a blue 2005 instead of a gray 2007, more miles on the odometer and lots more money in the bank.
 

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What ever you do don't let go, heh Graywolf. I've had it start 3 times 2 on my ST at over 125 and once on my V at over 115, all three time as soon as the front started to oscillate, I let off the gas and pushed on both handgrips as hard as I could (like a damper) all three times I road it out, but it scared the hell out of me. I don't recommend it.
 

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I didn't have enough leverage to stop it. Eventually, holding on isn't an option. The oscillations are too strong.
 

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On my way to work Friday when the same thing happened to me, I was going 110 and had what I though was a light wind. It just started to walk a little back and forth so I let off. It never happened when the wind wasn't blowing, though.
 

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For those of you with a Scotts installed - I have GenMar 1"up/1"back bar risers installed. Can I install the Scotts damper with the risers on? I've e-mailed this question to Scotts but not yet gotten a reply.
Thanks,
Kent
 

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NM_Eman,
See if you can get your hands on instructions for installing a Scotts and it should give you the info you want. From what I have seen of them you can't.
 

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You need a riser that has a 7/8" round lower portion that is clamped between the stock lower clamp and the Scotts upper clamp. Then a taller rise is required to clear the damper.
 

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I had one @ 100+ on a ZRX1100...not fun.

Someone had told me to just let go of the bars if it ever happened, so I did and the bike settled down...1/4 mile and 3 lane changes later.
 

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Mine started at 119 indicated, 110 actual and it did not settle down.
 
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