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Discussion Starter · #1 ·
hi guys, not sure if tho is the right thread to post this, my apologies if so

was wondering if anyone has had an issue with head shake/ high speed wobble on their dragster at about 110-120kph? was on low rpm and higher gear

got this uncontrollable head shake and threw me to the ground damaging everything on the bike except for the frame/chassis and engine. dash/display, key, head light, handle bars bent, bracket, all plastic panels, radiator, seat, pegs..etc .. everything gone.

luckily, all the protective gear saved my life. got barely any road rash but left with a scaphoid fracture on my wrist. been put on a cast for three months, and possibility of surgery.

was wondering if this has happened to anyone and if this is a defect on the bike?
 

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You Are kidding,something else is at play ,120 kph is not high speed. Did your forks collapse or any visible clues.
 

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Ouughhh.....
Glad you have only a fractured wrist...

I've never had this on my Dragster, will be hard to find out now but like Eddy mentioned, should be something else at play....

Get well soon mate !!
 

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Sorry to hear about this, definitely something wrong. I own a Brutale but have ridden the Dragster and at speeds above 120kph and had no issues at all.

I hope you can find the fault amongst the mess, glad to hear your not too seriously injured :(
 

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Discussion Starter · #5 ·
thanks guys.

there was nothing wrong previously. there were no other visible clues… used the same road as usual… have taken this bike at 220kph and no issues… found it really strange that i got this wobble at 120kph..ride the bike between 120-160 everyday. this time at 120, totally random and was uncontrollable.
 

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Amish, sorry to hear of your off but glad you're not badly hurt.
I can’t speak to the Dragster but the F3’s are known to have very light steering which make them susceptible to head shake. The one complaint many of us have is that the F3’s should all come from the factory with a steering damper. I’ve read on here and other forums of people mounting dampers to other 3 cylinder MV models as well.
You do not explain the exact situation as to road conditions, elevation, slight rise, hill corner etcetera. Is it possible that the front end became light and upon returning to full grip was slightly off from straight which began the oscillations that caused you to lose control?
Again, sorry and hope you heal quickly.
 

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Amish, sorry to hear this and glad your ok. Certainly the bikes are frisky but not unstable, even on bumpy rough roads the bikes feel stable and at the speed you quote nothing should have made that happen.

Good luck with sorting this out.

jimboF4
 

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do they have a steering damper? My Brutale had a very loose front end until I dialed up the damper
 

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I thought I'd just shift the discussion towards why a bike may become unstable at the front end.

There are several factors that can contribute to an unstable, head shaking motorcycle.

From the factory, the constant factor on the Dragster will be the rake & trail.

The less rake & trail a bike has the faster it will turn in. Reducing rake and trail by either dropping the triple clamps down the forks or increasing the swingarm angle will, potentially, reduce rake & trail to the point of instability - even when ridden in a straight line.

Other factors that reduce stability will be tyre geometry (profile), tyre pressure & road undulation (generally when the bike is leaner over and travelling at speed).

Please know that installing a steering damper and tweaking its nipples up to a high resistance setting is a mechanical fix to an issue who's source lies in geometry. And the geometry is unchanged with the installation of a steering damper.
 

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Only thing I can add maybe you blew a tire valve and front deflated quickly, maybe not even all air lost. As said before 110 to 120 is low speed and no bike that I have ridden (ever) headshakes at that speed. Any mechanic worth his salt should be quickly on top of any mechanical issue, should be very visible. If nothing is wrong with the bike (and this is not an inherent MV fault believe me)....then you have a problem because it's something you did. I have actually tried to get my daughter's F3 (not Dragster) to headshake on the track and if I let go the bars it straightens itself out.
 

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Hi Amish, hope you recover fully and quickly man. As for your crash, I agree with the last two guys, I don't think a steering damper is a fix for a mechanical problem or a setup issue. The Dragter might benefit from a steering damper in some situations, but I don think it would have helped you.
One thing most people do is look towards the front end of the bike for problems related to head shake, and wrongfully ignore the rear, it could have been a problem either end of the bike.
We can just speculate though.
 

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One thing most people do is look towards the front end of the bike for problems related to head shake, and wrongfully ignore the rear, it could have been a problem either end of the bike.
We can just speculate though.

wise words, I have seen many spend good money on a steering damper to address handling problems when in reality 10 minutes, a screwdriver and someone who knows what their doing can have the same results. Certainly the case with the B3 Brutale.

I would have suggested you may have had a tank slapper due to a combination of road surface and hard acceleration as I once had that at only 30-40mph, I was overtaking a car, accelerated hard, hit a bump/raised drain cover in the road which induced a slapper so violent it shake the brake pads back out of the callipers, I managed to stay on but it was no fun that's for sure!

But as you say you were at steady speed, low revs then maybe not. Did it happen suddenly or get progressively worse, did you go over a bump in the road and get the front wheel crossed up at all?
 

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Discussion Starter · #15 ·
hi guys… thanks on the advise about the steering dampener… was contemplating in purchasing one..

tyre pressure, calipers, pads everything all ok… so really surprised…

the head shake started all of a sudden and within mili seconds the head shake got insanely worse.. all happened so quickly and the next thing i knew the bike was sliding in front of me and i was tumbling/rolling sliding……..

i have had head shake on the bike previously on hard acceleration and high speed at about 180-190kph but it always straightened out.. this i found very strange and happened for the first time in my 9 years of riding bikes.
 

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hi guys… thanks on the advise about the steering dampener… was contemplating in purchasing one..

tyre pressure, calipers, pads everything all ok… so really surprised…

the head shake started all of a sudden and within mili seconds the head shake got insanely worse.. all happened so quickly and the next thing i knew the bike was sliding in front of me and i was tumbling/rolling sliding……..

i have had head shake on the bike previously on hard acceleration and high speed at about 180-190kph but it always straightened out.. this i found very strange and happened for the first time in my 9 years of riding bikes.
Well if the bike was not 'at fault' from a tech perspective...that only leaves environment and rider.
 

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Hi Amish, hope you recover fully and quickly man. As for your crash, I agree with the last two guys, I don't think a steering damper is a fix for a mechanical problem or a setup issue. The Dragter might benefit from a steering damper in some situations, but I don think it would have helped you.
One thing most people do is look towards the front end of the bike for problems related to head shake, and wrongfully ignore the rear, it could have been a problem either end of the bike.
We can just speculate though.
How about suspension setup ???
Especially rear suspension !
 

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Amish, I've read a lot about people's experiences with tank slappers, and yours sounds typical. My track bike sometimes shakes its head when going over a crest on the gas when the front end gets light, and even with a steering damper, it still shakes. It has its rake reduced with a Ducshop Reduced Offset Triple Clamp, and thus is even more susceptible to head shake, so I replaced the stock steering damper with an Ohlins adjustable one. But it still shakes.

Most tank slappers are inexplicable. Stories that I've read where people ride their way out of them usually include not rolling off the gas, but instead gradually rolling on more throttle. I believe this is because rolling off the throttle loads the front end suspension while it is oscillating back and forth, and that just exacerbates the problem, whereas rolling on throttle causes less dependency on the front end for stability.

Ducati Monsters were notorious for tank slappers, and this one was described in the early 2000's by a Monster owner:

Rear suspension 100% stock, with the sag set correctly by a suspension expert. Front suspension at stock height, but with slightly stiffer than stock springs, and sag set correctly by a (different) suspension professional. (I weigh just over 200 pounds in full riding gear, so stock springs are too soft.) Bars were stock. Tires had good tread, no cupping or anything, and were inflated to 33/35 front/rear. Bridgestone BT-020 front and rear.

The forks had recently been revalved and springs stiffened, but that clearly fixed several other handling problems that it had had before then. Previously, braking into a bumpy turn could cause it to ride like a jackhammer until the brakes were released. It was tracking better than ever with the modification. I can't blame the forks directly.

Tank slapper was caused by crossing a cattle guard at 40-50 mph on an uphill section. Bike was probably in 4th gear and speed was either steady or very slight acceleration. The road was almost straight, but not quite.

I'm guessing the cattle guard caused the front wheel to bounce off of the pavement slightly and come back down less than perfectly straight. The bike seemed to instantly go to full lock, oscillating 5-10 times, then tossed me off and began sliding on down the road. There was no warning that it might do something like that and only about a second to "enjoy the ride".

I've had dozens of experiences with headshake while accelerating out of bumpy corners or landing wheelies a little off and the bike had always settled right down. There had never been a scary moment before this incident.

I'm pretty sure that a steering damper would have saved me.​
 

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don't listen to those guys. Get a steering dampENer. :popcorn:
:laughing: Or just get the steering moistener, and be done with it.
 
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