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Discussion Starter #1
Just wondering if anyone has experienced tank slapping with the SS?

I've had it happen twice now .. once when I gave it full throttle in sport mode off the lights using quick shift. Front wheel came up on first, and then as I quick shifted to 2nd, the front wheel touched the ground and then as it lifted off again, start tank slapping. The 2nd time, when I throttled hard in 2nd gear out of a tight corner on a steep climb with a bumpy road.

Background on my bike, I've had the suspension properly setup for me, have fitted a 14 tooth front sprocket, run Michelin P5s and installed a Termi system. No ECU mods.

Thoughts on this? Rider error? Or setup on front suspension? Or does it need a dampener?
 
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@Ducagirl The SS is pretty stable for a sport bike. Personally, over more than 3 years, and about 15,000 miles of spirited riding in all kinds of conditions, I have not experienced tank slapping.

But in your second comment about: throttling hard, in a corner, uphill, on a bumpy road... I could see it happening in those conditions on many bikes, and wouldn’t add a damper because of that. And would throttle back under those conditions.

Other Forum member comments?
 

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Let me make sure were talking the same jargon. You're saying that under heavy acceleration your bars are moving back and forth "on their own"?
Yes, that's a tank slapper and yes a steering damper helps with the situation as does not accelerating quite as hard. The damper isn't a magic tool though and all it does is dampen the oscillation of the bars. The reasons the tank slapper happens still exist.

My opinion from riding the crap out of my SS and other bikes, on track and off, is that the damper is nice to have but the best thing is to learn to control your wrist better and be as loose as possible on the bike. The more steering inputs you put into the bars without knowing it the worse the situation becomes. I've seen plenty of crashes of high end sport bikes due to hard acceleration out of a corner then death gripping the bars and rolling off the throttle...

But anyways that's just my opinion.
 

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All I can add is that I've never experienced any weave, bar rotation or tank slapper. I can lock the throttle and ride the bike with no hands. It's easily the most stable bike I own.

But I've also never got it to wheelie with brisk acceleration nor have I actually tried to wheelie it by revving it and dropping the clutch.

Keep us posted and perhaps we can provide more info.
 

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If I might ask: are you certain the suspension was properly set up?
I had the same thought...

If you come down with the wheel crossed up you can get a tankslapper. in the video above Moss talks about how twisting the throttle in the wrong way can cause you to cross up when the weight is off the front wheel.

Most of the causes seem to be suspension related.

So, the question is, who set up the suspension and is it correct for Ducagirl's weight, height, riding position, and riding style?
 
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Having worked out a weave on my V11 Sport, if it were a suspension issue, I would speculate that the front is too stiff and the back is too soft. I'd try to soften up the front. Also check tire pressure. Make sure the front isn't overinflated.

The stiff front causes a lot of deflection that's transmitted to handlebars.

I'm not saying that suspension is the issue, just passing on some personal experience. As I said before, I've never even gotten my SS to wheelie. And my bike is stable as a rock.
 

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Discussion Starter #9
Great questions and insights .. thanks so much!

So yes it's definitely a tank slapper - and it's terrifying. I guess I'm lucky that I knew instinctively to relax my body and slowly ease off on the throttle to settle it down. Being high sided off a tank slapper is not something on my bucket list lol

So in terms of stability, I think it's the bomb but then it's set the high bar for me, as the only other bike I've ridden is a CBR500R.

My suspension was setup by a well-recommended specialty suspension tuner in Sydney - and for my weight and style. He did say that he'd set it up quite stiff at the back. I was really happy with how it rode afterward because beforehand it wallowed a bit in the corners where afterward it was so responsive and definite. Is it set up right? No idea - I've only been riding a year and a half, so it's all a learning curve for me. So maybe the answer is to go back and get it checked...

It could also quite possibly be user error - watching that video on accelerating while unconsciously counter steering makes sense as to a common cause. I get the front wheel up on it quite often, especially since I put took a tooth off the front sprocket, because the reality is that I'm a ratbag on the bike - so I'm really keen on prevention rather than management. I'll make a point of being conscious of this and see how it goes under hard throttle.

Thanks for the feedback!
 
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Hi #Ducagirl. This bike is not prone to tank slappers and over the years the value of a steering damper has been well discussed and the answer is a resounding No, Not needed. I am going to put your mishap down to rider error. By the way i have don it myself at least 4 times that i can remember. each time was my error riding very spirited and lifting the front wheel while coming out of a corner while still leaned over and not placing it down straight.(great feeling when it goes well though) I will say that if i had made those errors on my GSXR i would have been in a bit of trouble but the SS handles them well. I had set up my suspension same as usual but found that (for my riding style) this bike likes to run with the rear higher than the front (never had another situation) a simple adjustment of the SAG & ride Hight. If you are going to Gun it out of corners and the front is lifting consider adjusting the front and back geometry to compensate then you don't have to come off the throttle followed by death grip which is probably the main cause of the tank slapper.
 

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Perhaps this is irrelevent for heavy motorbike wheels, but on a road bicycle, death wobbles or speed wobbles are often caused when the front wheel is out of balance. Just happened last week to my husband, for this reason.
 

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I encountered a few tankslappers during the early days of riding my CBR929RR. All involved hard throttle pulls that slightly lifted the front wheel, with the handlebars going slightly askew. When the front wheel re-contacted the ground it would trigger a tankslapper. As others noted, I've since learned you don't need to chop the throttle to go fast, and if you do have a tank slapper then relax your arms and ride it out. I'd suggest you work on your throttle technique - Keith Code's "A Twist of the Wrist" would be a great start.
 

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Discussion Starter #13
Thanks for all of the feedback.. I spent the whole weekend out riding and was focusing on what my hands were doing. Realised I have been putting pressure on the bar when I throttle, so am really making sure I'm aware of this and relaxing. Made a big difference - the bike is responding so much better in the corners as well. I'll keep working on it :)
 

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I've had this happen a few times when riding hard around the IOM when I have been pinned in 6th gear and a bump in the road has lifted the front wheel off the ground. Gently applying the rear brake whilst keeping relaxed and the throttle still pinned settles the front end again.

Since swapping to a V2 I have noticed how much more planted and stable it is compared to the SS but a lot of that will be down to geometry and C of G etc.

Matt
 

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All I can add is that I've never experienced any weave, bar rotation or tank slapper. I can lock the throttle and ride the bike with no hands. It's easily the most stable bike I own.

But I've also never got it to wheelie with brisk acceleration nor have I actually tried to wheelie it by revving it and dropping the clutch.

Keep us posted and perhaps we can provide more info.
I did run it hard coming out of a bending curve and might've gotten a little air under the front tire and got it to bobble on some uneven concrete road. Despite that it just settled and went straight.
 
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