Author Topic: weebles wobble  (Read 6345 times)

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Offline Retro Rocket

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Re: weebles wobble
« Reply #25 on: May 15, 2014, 08:28:09 PM »
Deceleration wobble beginning between 50-40 mph is very, very common.  It can happen with any style of bike.

I disagree completely, although it was common trait in older style bikes it is NOT a common thing these days, tire tech is a hell of a lot better, brass bushes, tapered steering head bearings and steering dampers and better shocks all help, if your bike is set up well it should NOT wobble at any speed, period.... There is a video here somewhere showing these wobbling 70's bikes, all were know to have inherent problems built in, not enough trail, wrong rake and trail combinations, poor suspensions, cheap bearings all of which can be sorted with the correct parts and maintenance....
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Offline Stev-o

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Re: weebles wobble
« Reply #26 on: May 15, 2014, 08:37:40 PM »
Deceleration wobble beginning between 50-40 mph is very, very common.  It can happen with any style of bike.

I disagree completely, although it was common trait in older style bikes it is NOT a common thing these days, tire tech is a hell of a lot better, brass bushes, tapered steering head bearings and steering dampers and better shocks all help, if your bike is set up well it should NOT wobble at any speed, period.... There is a video here somewhere showing these wobbling 70's bikes, all were know to have inherent problems built in, not enough trail, wrong rake and trail combinations, poor suspensions, cheap bearings all of which can be sorted with the correct parts and maintenance....

And the video has a guy wearing a scuba diving weight belt to stop the wobbles!
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Offline ofreen

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Re: weebles wobble
« Reply #27 on: May 15, 2014, 08:51:20 PM »
Deceleration wobble beginning between 50-40 mph is very, very common.  It can happen with any style of bike.

I disagree completely, although it was common trait in older style bikes it is NOT a common thing these days, tire tech is a hell of a lot better, brass bushes, tapered steering head bearings and steering dampers and better shocks all help, if your bike is set up well it should NOT wobble at any speed, period.... There is a video here somewhere showing these wobbling 70's bikes, all were know to have inherent problems built in, not enough trail, wrong rake and trail combinations, poor suspensions, cheap bearings all of which can be sorted with the correct parts and maintenance....

Modern bikes will do it.
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Offline Retro Rocket

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Re: weebles wobble
« Reply #28 on: May 15, 2014, 11:41:30 PM »
Deceleration wobble beginning between 50-40 mph is very, very common.  It can happen with any style of bike.

I disagree completely, although it was common trait in older style bikes it is NOT a common thing these days, tire tech is a hell of a lot better, brass bushes, tapered steering head bearings and steering dampers and better shocks all help, if your bike is set up well it should NOT wobble at any speed, period.... There is a video here somewhere showing these wobbling 70's bikes, all were know to have inherent problems built in, not enough trail, wrong rake and trail combinations, poor suspensions, cheap bearings all of which can be sorted with the correct parts and maintenance....

Modern bikes will do it.

I've had plenty of modern bikes Greg and none did it
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Offline Deltarider

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Re: weebles wobble
« Reply #29 on: May 16, 2014, 02:19:32 AM »
Quote
Deceleration wobble beginning between 50-40 mph is very, very common.  It can happen with any style of bike. Even a bike with everything in correct adjustment and appropriate tire pressure may do it, especially as a front tire wears.  You need to fix those swingarm bearings, but even after you do, you may have the wobble.  Every bike I've had from dirt bikes, dual sports, sport bikes and standard bikes have all done it to some extent.  Ask a Gold Wing owner of any vintage (bike, not rider) about deceleration wobble.

The advice the Hee Haw doc gave is valid.  If it wobbles when you take your hands off the bars, then don't do that.

I agree.

Quote
I disagree completely, although it was common trait in older style bikes it is NOT a common thing these days, tire tech is a hell of a lot better, brass bushes, tapered steering head bearings and steering dampers and better shocks all help, if your bike is set up well it should NOT wobble at any speed, period.... There is a video here somewhere showing these wobbling 70's bikes, all were know to have inherent problems built in, not enough trail, wrong rake and trail combinations, poor suspensions, cheap bearings all of which can be sorted with the correct parts and maintenance....

I disagree, that's why I posted that vid. It is still valid. The remedy is simple: keep your hands at the handlebars at all times and you won't be surprised.
For who is interested, here is the vid again:  https://www.youtube.com/watch?v=fvsDIq3WwVA
From 04:30 on.
Besides, how do you recognise a 'modern' bike. Is that in the vehicle documents? In the framenumber?
Better safe than sorry. And I am not going to mount a steering dampener. If Honda didn't fit one, if there's no law that demands one, if in over 100.000 kms I didn't experiende anything else than the common and depending on tyrewear deceleration wobble, if my dealer didn't want to sell me one and as long as I have both hands.


« Last Edit: May 16, 2014, 02:34:25 AM by Deltarider »
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Offline calj737

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Re: weebles wobble
« Reply #30 on: May 16, 2014, 03:39:23 AM »
+1 Gerbil. Find it, fix it, and be done with it. You're close and Retro's advise about the swing arm is probably the culprit if you've done the front end.

For the record, of all the miles and bikes I've owned and ridden, I've never had a front end wobble on deceleration. To suggest its normal it's utterly stupid. Some oscillation would be expected, but wobble? Hogwash! It would potentially cause repeated tank slippers under heavy braking, and no manufacturer is that stupid.

Some of these internet experts make want to throw away my devices...
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Offline Stev-o

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Re: weebles wobble
« Reply #31 on: May 16, 2014, 03:48:38 AM »
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Offline Deltarider

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Re: weebles wobble
« Reply #32 on: May 16, 2014, 04:15:31 AM »
Wobble, oscillation. Could be my English is not good enough and I've ment oscillation.
BTW, what does the word Motorvatin' mean? (It's the title of an album.)
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Offline kghost

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Re: weebles wobble
« Reply #33 on: May 16, 2014, 04:47:08 AM »
That's the proper attitude mate....

I agree.
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Offline Retro Rocket

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Re: weebles wobble
« Reply #34 on: May 16, 2014, 04:51:55 AM »
Quote
Deceleration wobble beginning between 50-40 mph is very, very common.  It can happen with any style of bike. Even a bike with everything in correct adjustment and appropriate tire pressure may do it, especially as a front tire wears.  You need to fix those swingarm bearings, but even after you do, you may have the wobble.  Every bike I've had from dirt bikes, dual sports, sport bikes and standard bikes have all done it to some extent.  Ask a Gold Wing owner of any vintage (bike, not rider) about deceleration wobble.

The advice the Hee Haw doc gave is valid.  If it wobbles when you take your hands off the bars, then don't do that.

I agree.

Quote
I disagree completely, although it was common trait in older style bikes it is NOT a common thing these days, tire tech is a hell of a lot better, brass bushes, tapered steering head bearings and steering dampers and better shocks all help, if your bike is set up well it should NOT wobble at any speed, period.... There is a video here somewhere showing these wobbling 70's bikes, all were know to have inherent problems built in, not enough trail, wrong rake and trail combinations, poor suspensions, cheap bearings all of which can be sorted with the correct parts and maintenance....

I disagree, that's why I posted that vid. It is still valid. The remedy is simple: keep your hands at the handlebars at all times and you won't be surprised.
For who is interested, here is the vid again:  https://www.youtube.com/watch?v=fvsDIq3WwVA
From 04:30 on.
Besides, how do you recognise a 'modern' bike. Is that in the vehicle documents? In the framenumber?
Better safe than sorry. And I am not going to mount a steering dampener. If Honda didn't fit one, if there's no law that demands one, if in over 100.000 kms I didn't experiende anything else than the common and depending on tyrewear deceleration wobble, if my dealer didn't want to sell me one and as long as I have both hands.

That video is completely irrelevant mate, try posting something thats not over 30 years old, Old tires, poor suspensions, ball bearing steering head bearings and handle bar mounted fairings are all known to upset handling, i've already explained why its not a good comparison in another thread where you tried to convince everyone who doesn't know better, believe what you like but your wrong, simple as that.... Old bikes with known handling issues is NOT a good comparison at all and to try and argue that point with a noticeable lack of understanding of the problem doesn't make it right....  I can easily post numerous videos of fools falling off bikes that wander on under their own power until they are going slow enough to fall over without a wobble, how do you explain that under your reasoning Delta..?
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Offline calj737

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Re: weebles wobble
« Reply #35 on: May 16, 2014, 04:54:37 AM »
Finally! The voice of reason and logic prevails! Thanks, Retro for putting the internet to a good and proper use!

That stuff that gets propogated  :o
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Offline Retro Rocket

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Re: weebles wobble
« Reply #36 on: May 16, 2014, 04:57:18 AM »
Finally! The voice of reason and logic prevails! Thanks, Retro for putting the internet to a good and proper use!

That stuff that gets propogated  :o

And powered by beer..... ;D ;)
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Offline calj737

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Re: weebles wobble
« Reply #37 on: May 16, 2014, 05:12:40 AM »
This round is on me...
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"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline nccb

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Re: weebles wobble
« Reply #38 on: May 16, 2014, 05:16:16 AM »
now don't upset the aussies calj, they don't like fosters. ::)

Offline calj737

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Re: weebles wobble
« Reply #39 on: May 16, 2014, 05:19:36 AM »
I know, but at least they'll appreciate that I tried. I'm unfamiliar with their preferred brands, and didn't want to go on a lark.

They're a grateful lot who appreciate kind gestures, so I suspect they'll forgive my less than premium choice, knowing full well that if I were local, it would be top shelf only.
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Offline Stev-o

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Re: weebles wobble
« Reply #40 on: May 16, 2014, 05:22:10 AM »
Fosters......American for beer!  I like it. 
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Offline Sticky Gerbil

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Re: weebles wobble
« Reply #41 on: May 16, 2014, 05:28:12 AM »
 As far as Foster's go, I know I'm just a dumb American, but anything that isn't pisswater and comes in an oil can for a buck at Kroger is ok with me.

Thanks for the helpful responses to those who gave them. I tightened the swing arm about a half turn with a breaker bar, the bike still wobbles. I feel like the 1/4-1/2 turn I gave to the steering head made the condition worse, but I could just be hallucinating.

Again, I don't think tire wear is an issue with new tires. The chain adjusters are both at the same notch, and the front fork caps are tight as a mofo. I think that I am going to find when I remove the steering head that the bearings are flatted, and when I remove the swing arm that the bushings are toast. Neither of these seems hard to do, but it has been so warm and delightful out that I can't stop riding with my quasi-dangerous (or completely normal, depending on who you ask) wobble.

The other issue is lack of dinero, and my wife's car is pissing oil. I think she popped the pan (not a euphemism). This weekend I shall disassemble things and check them in the hopes that I can save some cash by actually diagnosing something rather than throwing parts at it or calling it normal.

Offline calj737

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Re: weebles wobble
« Reply #42 on: May 16, 2014, 06:04:38 AM »
Do also grease the swing arm bushing. That may help tide you over until you can rebuild that bushing.

It is possible to over-tighten the steering head: it needs some amount of lash. If the bearings are "notchy" and you crank them down too far, you'll end up with bad vibrations at a variety of speeds, and pretty unstable handling.

In the interim, if you can't replace them, at least pop off the top clamp and grease those dudes up really well. Be advised, there's about 17-20 individual steel balls in the race, so don't drop and lose any. You could alternate their placement and perhaps buy yourself a wee bit of time. I'd let the lowers go until you can replace everything. Top and bottom replacement takes a good weekend as most of the front end has to come down/apart.
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Offline BobbyR

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Re: weebles wobble
« Reply #43 on: May 16, 2014, 06:06:50 AM »
Tire pressure as I sad cauded mine, but you said you wre at 40 psi.  Head bearings are cheap, I bought a set because I was lazy. If you check it out they are common roller bearings you can get from a suplier.

In the mean time if the bars don;t wobble with your hands on  them, ride the sucker!
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Offline ofreen

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Re: weebles wobble
« Reply #44 on: May 16, 2014, 06:09:17 AM »
Oscillation is a good word.  All anyone needs to do is google "deceleration wobble" and they will find plenty of info on the topic, including explanations of the physics behind it.  By all means, the OP should make sure his bike is adjusted and tires inflated correctly and otherwise in good repair.  All I am pointing out is that even after doing that, the wobble may still be there, especially as the tires wear.  Some bikes are worse than others.  Several Honda models are notorious for it.  I used the Goldwings as an example above, but CBRs, Sabres and Shadows are known for it as tire wear occurs if you want to talk about diverse Hondas.  Sport bikes with their rigid frames and steep steering geometry are very prone to it, again especially as the front tire wears.  It can be minimized and may even stop with new tires and some bikes are more prone to it than others.  But it is not particularly dangerous by itself.  What can be dangerous is taking your hands off the bars during deceleration.  There simply is no reason to do that.
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Offline calj737

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Re: weebles wobble
« Reply #45 on: May 16, 2014, 06:17:07 AM »
It's pretty dang hard to imagine a scenario would a rider could and would have their hands off the bars under deceleration. Are they braking with only their foot while combing their hair? It's an absurd scenario.

The statement above constantly goes back to "tire wear" which is not symptomatic of an embedded design flaw or physics related flaw. Let's just agree that with any state of neglect on the proper condition of the suspension system (including the tires) that steering problems are likely.

I think it's safe to deduce from the OPs findings that his swing arm and steering head bearings are neglected and badly worn. Dollars to donuts that once he's able to address that, his wobble goes a wandering. Of all the threads I've ever read here, I've never seen a reference to "that dreaded customary steering wobble" from the old SOHCs.

As Retro said earlier, believe what you wish, but there's too much evidence to refute this position.

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Offline Sticky Gerbil

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Re: weebles wobble
« Reply #46 on: May 16, 2014, 07:51:19 AM »
^^^
Fair enough. The reason I noticed the wobble is because I don't white knuckle the bars as I have pretty bad carpal tunnel. I felt a difference one day and was like, what the hell? So I took my hands off the bars and they jiggled within my closed fists. As a mechanic, I am always thinking, when does x vehicle do y thing? So I repeated until I isolated the speed and conditions.

I checked out hondaman, his prices are really high and turnaround time sucks. I feel as though I could press swingarm bushings in and out and replace the steering head bearings in a day. Maybe less.

Do you guys think it's worth it to try and find needle bearings for the swingarm? What about tapered bearings for the head?

Offline Sticky Gerbil

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Re: weebles wobble
« Reply #47 on: May 16, 2014, 10:43:55 AM »
So my local Honda has 2 swingarm bushings on hand for $31 each. Think I'm gonna grab em today.

Offline Deltarider

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Re: weebles wobble
« Reply #48 on: May 16, 2014, 10:58:19 AM »
Still I don't know the meaning of the word Motorvatin'. What does it mean?
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Offline nccb

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Re: weebles wobble
« Reply #49 on: May 16, 2014, 11:48:15 AM »
Still I don't know the meaning of the word Motorvatin'. What does it mean?

what is the context?  I couldn't find it in the thread.  I am assuming its a play on words - motivating and engines (motors) = motorvating leaving out the g for dialect.