Head Wobble at highway speed

[chilloutdamnit]

Is it normal for the front end wobble under sudden jerky steering input at speeds near 80mph? The bike feels stable at the same speed with a light grip on the handlebars.

Looking at some of the previous posts, it's hard to tell if their head wobble is there whenever they get up to speed or if it's just sometimes.

[adidasguy]

Tire balance?
Worn tires?
Bad bearings?
Rough road?
I've taken Suzi up to 80 or 85 and she rides really smooth. Except for a section if I-5 between Boeing Field and 405 where at that speed, the bumps in the poorly poured concrete match the resonant frequency of the bike and you'd swear the tires just went flat.

[chilloutdamnit]

I put on a new front tire ~2,000 miles ago. The wheels were professionally balanced and installed.The road was just repaved and was extremely smooth. It was slightly windy by the coast.  I should check the air pressure and the bearings.

So wobble is never normal even with sudden jerky steering input?

[numus]

I put on a new front tire ~2,000 miles ago. The wheels were professionally balanced and installed.The road was just repaved and was extremely smooth. It was slightly windy by the coast.  I should check the air pressure and the bearings.

So wobble is never normal even with sudden jerky steering input?

My front fender became loose and i noticed it started moving a lot at high speeds and jerking the front of the bike around... Maybe worth a look?

[adidasguy]

"Sudden jerky steering input" at 80 mph? I don't think any bike likes that and is probably trying to tell you to stop doing that.
At that speed, I do normal steering.
Maybe you can explain what you're doing. 
I wouldn't do "sudden jerky steering" even in a car at 80 mph.

[chilloutdamnit]

I was following a pick up truck on a windy highway when some debris flew out of the bed. It was just a plastic bag, but my natural instinct was to weave around it. Most of my weaving practice have been at speeds under 45 mph, so I turned the bars a little harder and faster than I think the bike liked. There was a slight wobbling of the front end, but the bike righted itself afterward.

The feeling of wobbling was so foreign that I it a few more times before I came to my senses and stopped.

[mister]

So you did a Sudden jerk at speed and got a brief wobble which corrected itself, is that it?

Or, after this there is now a Constant Wobble at speed?

How Stiff are your arms on the bars?

Michael

[chilloutdamnit]

So you did a Sudden jerk at speed and got a brief wobble which corrected itself, is that it?

Yes

Or, after this there is now a Constant Wobble at speed?

No

How Stiff are your arms on the bars?

Not sure how to quantify this. I don't have a death grip.

[mister]

Lose grip - lose as will allow to still hold the throttle - and bent and relaxed arms is correct riding position for optimum handling ability.

What you did was to upset the bike's geometry. ALL two wheel machines have a Natural Tendency to Self Correct to maintain balance and control. The wobble is this happening as you take the direction from straight to suddenly left/right, the front wheel wants to come back and does so, sometimes over shooting the original liine, then needs to correctly come back again. The Wobble is affected by a change in speed and steering input stiffness, and other factors. So, as soon as it happened and a change in speed followed (no matter how minor) the Wobble Forces changed/dissipated.

Michael

[chilloutdamnit]

Lose grip - lose as will allow to still hold the throttle - and bent and relaxed arms is correct riding position for optimum handling ability.

What you did was to upset the bike's geometry. ALL two wheel machines have a Natural Tendency to Self Correct to maintain balance and control. The wobble is this happening as you take the direction from straight to suddenly left/right, the front wheel wants to come back and does so, sometimes over shooting the original liine, then needs to correctly come back again. The Wobble is affected by a change in speed and steering input stiffness, and other factors. So, as soon as it happened and a change in speed followed (no matter how minor) the Wobble Forces changed/dissipated.

Michael

Awesome! Thanks for your explanation.

[Dizzledan]

I saw the title of this thread and thought it was a solution to the wind smacking my helmet around on breezy days. I don't need no stinking windshield!

[Oracle]

ever get a gust of wond strong enough to try to pull ur helmet off? .... im thinkin its just me and i need to get a better fitting helmet.

[Twisted]

ever get a gust of wond strong enough to try to pull ur helmet off? .... im thinkin its just me and i need to get a better fitting helmet.

Or one that is better designed. Some of the cheaper helmets I used to wear when I went for quick runs used to do this.

[Oracle]

its a shark s650 not the cheapest but not the greatest. alittle tight on the bottom but loose at the top. happens alot at 75mph and especially when i turn my head. but surprisingly its comfortable.

[Erika]

Most of my weaving practice have been at speeds under 45 mph, so I turned the bars a little harder and faster than I think the bike liked. There was a slight wobbling of the front end, but the bike righted itself afterward.

The feeling of wobbling was so foreign that I it a few more times before I came to my senses and stopped.

Do you know what counter steering is? No insults intended... just trying to help. I never turn my bars, I push them... if you know what I mean. Or not. If not, you may want to look this up so you don't hurt yourself. (I'm really not trying to be insulting, I'm being sincere... and concerned.)

[scottwalker]

I thought I would post my experiences with high speeds.  I am a new rider this year.  I have the GS500F.

Helmet = Shoei RF-1100

Windshield was stock but too much wind hitting me in the chest so I bought a double bubble zero gravity.  Fixed that problem.  Very nice.  It pushes the wind up and over.

As a new rider I was inexperienced.  I lift weights and first riding attempts I would target fix really bad and try to muscle the handlebars around.  Another thing that was bothering me was picking up wind draft turbulence from other large vehicles on the interstate at 70+ mph.  It was bouncing my front tire all over the highway.

I watched the "Twist of the Wrist" dvd and figured out that my death grip on the handle bars was most of my problem.  The motorcycle wants to drive straight and my over gripping the bars was transferring the wind turbulence into the front tire.  Very bad.  I have learned to relax and let the bike do the driving and I am easy on the bars.  World of difference.  Very nice riding now.  The GS500F rocks man!!!!   

[chilloutdamnit]

Do you know what counter steering is? No insults intended... just trying to help. I never turn my bars, I push them... if you know what I mean. Or not. If not, you may want to look this up so you don't hurt yourself. (I'm really not trying to be insulting, I'm being sincere... and concerned.)

Sorry, I meant "push". I am aware of what countersteering is.

[jacob_ns]

Check your steering bearings by getting the front tire off the ground and slowing moving the handlebars left to right. If it binds, feels notched or drops at all, regrease or replace the bearings. Also, have someone hold the handlebars while you try and move your front wheel side to side and up and down to check your front wheel bearings. Same applies, replace if necessary.