head shake over a bump

[sidwin]

i had the weirdest experience the other day. i was riding in the rain at 45mph. right hand on the bars and went over a bump. bike started to head shake pretty good. i thought it would stop but after a a couple of seconds it didn't. when i put my left hand back on the bars, it went away.

so what caused it and is there another way to solve the problem? clutch, throttle modulations? my head nut is pretty tight.

Thanks,
Sid

 

[[email protected]]

I had the same exact symptoms shortly after I got my bike. Tightening up the steering stem bearings did the trick for me.

http://www.youtube.com/watch?v=OW-CmACI5xQ

 

[one2dmax]

Loose or worn steering head bearings.

 

[sidwin]

i tighten it up wheni first got it... watched sean's video. when i did it. i guess i can do it again.

thanks,
sid

 

[tothemax93]

Bearing could be bad. my bike had slight head shake with one hand on. The bearing had a flat spot. I changed it out.

 

[MaxMidnight]

....right hand on the bars and went over a bump. bike started to head shake pretty good.

....when i put my left hand back on the bars, it went away.

Sid, I think you have answered your question - keep both hands on the bars.

 

[94 V-Max Rider]

i had the weirdest experience the other day. i was riding in the rain at 45mph. right hand on the bars and went over a bump. bike started to head shake pretty good. i thought it would stop but after a a couple of seconds it didn't. when i put my left hand back on the bars, it went away.

so what caused it and is there another way to solve the problem? clutch, throttle modulations? my head nut is pretty tight.

Thanks,
Sid

Could be nothing, or it could be your steering bearings. I'd elevate the front wheel and move the bars from left-to-right. If you feel any resistance or anything short of smooth, the bearings and races will need to be replaced; feel for a notch in the center, which would indicate that you have a dented race(s). If all of that checks out, perform the bounce test, as shown Sean's video above. They could just need an adjustment.

Of course, it's always wise to ride with both hands on the handlebar.

 

[Miles Long]

Sid, I think you have answered your question - keep both hands on the bars.

+1 . Don't become another statistic, because of any easily preventable accident.
As for that headshake, I had low speed problems at 30-50 kph. I adjusted the headstock bearings, to no avail. Then I did the "Furbur fix" procedure. No more low-speed wobbles. That was about 50,000 k. ago.
Let the debate begin! (or should I say, continue?)
Cheers!

 

[rusty]

i tighten it up wheni first got it... watched sean's video. when i did it. i guess i can do it again.

thanks,
sid

That shake could be nothing more then a worn or cupped front tire.:biglaugh:

 

[94 V-Max Rider]

+1 . Don't become another statistic, because of any easily preventable accident.
As for that headshake, I had low speed problems at 30-50 kph. I adjusted the headstock bearings, to no avail. Then I did the "Furbur fix" procedure. No more low-speed wobbles. That was about 50,000 k. ago.
Let the debate begin! (or should I say, continue?)
Cheers!

I'm not sold on the "Furber Fix." I just replaced and adjusted my steering bearings, rebuilt my forks using Race Tech springs and bushings, dialed in the static sag, balanced the front wheel, and made sure everything was was aligned properly. The bike rides beautifully. Moreover, I have yet to receive a plausible explanation with regard to what the Furber Fix is exactly supposed to accomplish that can't be remedied through routine inspection and maintenance. I hate to sound like a cynic, but my take is that the "fix" is just be a band aid for other problem(s).

 

[jfeagins]

Once I found the secret of maintaining clean blinker fluid, all my head shake problems went away, and as long as I change that blinker fuid every spring, I don't think it'll ever be a problem again.



Oh, and there was this loose nut holding my handlebars too.

 

[94 V-Max Rider]

Once I found the secret of maintaining clean blinker fluid, all my head shake problems went away, and as long as I change that blinker fuid every spring, I don't think it'll ever be a problem again.

View attachment 35266

Oh, and there was this loose nut holding my handlebars too.

Blinker fluid?

 

[jfeagins]

Blinker fluid?

You did all that other stuff, and you didn't change out your blinker fluid? :bang head:

Good lord man, I wouldn't even venture out around the block with that bike yet. You'd be on borrowed time.

 

[davesax36]

Carb chain not torqued properly.
/thread

Sent from my Galaxy Nexus using Tapatalk 2

 

[[email protected]]

Oh, and there was this loose nut holding my handlebars too.

That seems to be the cause of many problems!

 

[dannymax]

Very difficult to nail down these head shakes, what Sid is describing is the 'low speed wobble'....by far the most diserable of the two available wobbles! The other one being the 'high speed wobble' which kicks in around 125 - 135 mph....you DON'T want to experience this one!!

What causes them....:ummm:

Sometimes bad or loose head bearings/races, cupped tires, wheel bearings, swingarm bearings, excessive rotating mass, a fat lady on the back, a skinny lady on the back, low blinker fluid, carb chains out of adjustment, or maybe just the petro flopper-gloppers out of sync.

Here's a list of foolproof wobble fixes......









unk:

 

[Miles Long]

What causes them....:ummm:

Sometimes bad or loose head bearings/races, cupped tires, wheel bearings, swingarm bearings, excessive rotating mass, a fat lady on the back, a skinny lady on the back, low blinker fluid, carb chains out of adjustment, or maybe just the petro flopper-gloppers out of sync.

......or natural frequency (critical speed) excitation of the front end, caused by the frequencies generated by the front tire and wheel at 30-50kph. The two collide, and the poorly dampened front end shakes uncontrollably, until the exciting force is removed (slower than 30, or higher than 50 kph)
Which is why the Furbur fix works, in some cases. removal of the rubber washer changes the natural frequency of the front end (mainly the forks and trees), so that it is not excited by the lower-speed revolutions of the front wheel assembly.
Just a guess....
Cheers!









unk:[/QUOTE]

 

[sidwin]

i was doing a 300 mile ride... i was just resting my left hand for a little. i try to alternate between left and right hands...

tires are pretty new. 2000 miles at most on them. bike has 6000 miles on it. I replaced the fork springs with progressives and rears with a set too recently. definitely low speed wobble.

my question is this... The gyroscopic effect of a bike is supposed to keep it up. what would have happen if i had no hands on the wheel? at that low speed why didn't the bike settle itself out? one of my riding friends said it was probably my right hand jerking the bar causing the wobble.

i've ridden across drawbridges and that wobble is predictable... this was the worse i've ever seen. it shook so fast it was amazing.. it didn't go all the way tank slapping but the frequency of the wobble surprised me.

Thanks,
Sid

 

[KJShover]

No hands on it, it would shake and you would fall over. Do the bounce test. Your head might be loose. Tighten it up and it will be better.

Mr. Morley will show you how...

http://www.youtube.com/watch?v=OW-CmACI5xQ



.

 

[MaxMidnight]

My question is this... The gyroscopic effect of a bike is supposed to keep it up. what would have happen if i had no hands on the wheel? at that low speed why didn't the bike settle itself out? one of my riding friends said it was probably my right hand jerking the bar causing the wobble.

If you want to know more about motorcycle dynamics have a read of this...there will be a test at the end. :confused2:

I suspect your friend was correct - inappropriate right hand jerking is known to cause (amongst other things) wobbling of handlebars and also blindness is done too often.