Author |
Message |
Grimace308
| Posted on Wednesday, December 28, 2005 - 02:11 pm: |
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not to appear flippant, but does the headshake ONLY appear with hands off the bar because i like to keep my hands on the bars to avoid the horrible minnesota drivers...that try to kill us...on sight...all the time... |
Aeholton
| Posted on Wednesday, December 28, 2005 - 02:48 pm: |
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My headshake only appears with hands off the bars. I don't feel any shake with my hands on the bars. |
Chadhargis
| Posted on Wednesday, December 28, 2005 - 02:49 pm: |
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To me, headshake is a violent thing. Like a tankslapper or impending tankslapper. Is this what is happening, or is it simply a weave? |
Namibian
| Posted on Wednesday, December 28, 2005 - 03:41 pm: |
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Chad, Mine is a SLIGHT oscillation that almost feels like a harmonic vibration. The actual bar movement side to side/fore to aft seems to be +/- 1/8-1/16" AT MOST. Simple answer, keep hands on the bars where they should be! John Becker |
Eor
| Posted on Wednesday, December 28, 2005 - 04:37 pm: |
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When the Buell tech first rode mine, he said the bars almost went "lock to lock" on him but I never experienced it to that degree, perhaps because I never had the nerve to get my hands far enough from the bars to allow that to happen. The conversation I had with Buell tech support regarding the issue was identical to Csg's. With hands normally on the bars, it is not noticeable. I now just consider it a quirk of my bike. |
Thunderbox
| Posted on Wednesday, December 28, 2005 - 04:41 pm: |
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Have you looked for a steering damper. I would think that would completely correct this condition. Any available. |
Blake
| Posted on Thursday, December 29, 2005 - 12:36 am: |
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Five stars for Thunderbox for calling it a "damper"! Way to go sir! |
Brad1445
| Posted on Thursday, December 29, 2005 - 01:33 am: |
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5 more stars to a link where I can buy one that fits. |
Mb182
| Posted on Thursday, December 29, 2005 - 09:46 am: |
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These Guys have one www.americansportbike.com MB |
Brad1445
| Posted on Thursday, December 29, 2005 - 10:40 am: |
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Thank you, now may I borrow $350.00? |
Mb182
| Posted on Thursday, December 29, 2005 - 11:32 am: |
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The Interest rate is a Killer I bet if you call Scotts, they have one that will work... probably cheaper. |
Lowflyer
| Posted on Thursday, December 29, 2005 - 11:51 am: |
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Blake, Two words: 'irregardless' and 'gage' Love, Lowflyer |
Blake
| Posted on Thursday, December 29, 2005 - 03:19 pm: |
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heheheh... I'll see your "irregardless and "gage" and raise you a "commingle." |
Lowflyer
| Posted on Thursday, December 29, 2005 - 03:54 pm: |
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COMMINGLING - In finance and accounting, to mix or mingle financial information from two or more separate entities. For example, business financial records must be kept separate from personal financial records. To commingle business and personal money is illegal. |
Blake
| Posted on Thursday, December 29, 2005 - 06:35 pm: |
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Right... "commingling" same-same as "mingling", no? That "commingling" indeed is a proper word makes no sense to me. Had a big problem in the shop once; some shear-head fasteners were reportedly "commingled" with their tension-head brethren. |
Lowflyer
| Posted on Friday, December 30, 2005 - 10:51 am: |
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I think mingling is something you do in a room full of strangers. Commingling is done among friends. Better yet, mingling is someting you do to some one. Commingling is done with someone. (Message edited by lowflyer on December 30, 2005) |
Jim_sb
| Posted on Monday, January 02, 2006 - 05:50 pm: |
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Hi guys, I'm back from a little vacation....... Blake, I was just giving my 2 cents. Nothing absolute. But if the minimal engine braking is causing the 5th gear headshake below 50mph due to fork compression I'd sure be surprised. No, I'm not an engineer, Yes, I don't know much about bikes except that I like to ride them. <g> As for the severity, it's NBD at this point AFAI concerned. The bike is very rideable and this won't slow me down. If it ever gets to the point where it concerns me I'll look for a steering damper. I am not upset or anything, but I will continue to monitor things closely. My gut feel (again, worth 2 cents or less) is that it's related to engine vibes being transmitted to the bars through the rubber donuts. Maybe we need a multi-compound donut - a softly tuned portion for the low vibes and a "hard" part for the high rpm stuff. If such a thing is possible. <ggg> Regards, Jim in Santa Barbara |
Redne_dab
| Posted on Tuesday, January 03, 2006 - 12:01 am: |
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Interesting. In this thread, the conclusion is that the weave (head shake makes it sound overly dramatic) is due to engine harmonics. In the following weave thread -tires are the suspected culprit. The best theory I've heard is insufficient weight on the bars. Of course, I don't even have one yet. Fun stuff. |
Eor
| Posted on Tuesday, January 03, 2006 - 02:45 am: |
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What's the frequency, Kenneth? Electrical and mechanical devices oscillate at a certain frequency. In electronics, when a circuit in tuned to its resonant frequency the transfer of power is the greatest. I think the addition of the luggage racks and bags alters the oscillation of the bike but a complex of other variables determines whether that oscillation is perceptible to the rider through the bars. These variables, such as a rider's weight, engine speed, power train efficiency, aerodynamic resistance, tire wear, road surface, etc. must combine in a certain configuration to resonate the bike to that frequency. The reason I believe this.... Several of the things they tried with my bike seemed to slightly change the range of speed at which the headshake occurred, its intensity, and the speed at which it was maximized. In essence, removing some or all of the bags, replacing the tires, re-torquing the steering head bearing, adjusting the suspension, or just having riders of differing weights and heights ride the bike in essence "tuned" the system, much like making a fine adjustment to a radio receiver. The headshsake never completely disappeared because the range of adjustments available were insufficient to null out the oscillation. There is a key variable present in my bike and a few others out there that should give some smart person the clue as to what is happening...some subtle deviation within manufacturing tolerances, either in the power train or the frame. My guess is that the only way to completely eliminate the phenomenon is to make a significant enough change in the geometry of the bike to alter the frequency of its oscillation...such as lengthening the wheelbase. This is the stuff of which MIT doctoral dissertations in applied physics are made, folks. If someone at the factory is trying to figure this out, I'll bet they are spending allot of quality time with modeling programs.... My prediction...the wheelbase of the 2007 XB12X will be about .25 inches longer. |
Electraglider_1997
| Posted on Tuesday, January 03, 2006 - 11:00 am: |
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Eor, We discussed the similar outcome of increasing the wheel base using a triple clamp that moves fork forward. The idea was to get more steering lock. Here is another thought. Loosen the triple clamps and raise the forks up maybe 1/2 inch. You'd probably have to go to Heli bar adaptor of some sort to accomplish this because the handle bar is currently the limiting factor (it's in the way). Anyway, I see this as a way of getting more weight on the front wheel. I've notice how my front wheel literally floats when my throttle hand gets excited. |
M2nc
| Posted on Thursday, January 05, 2006 - 07:31 pm: |
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Eor, I have to agree with EG97 here, I see you mentioned suspension settings, so this has probably been tried but here goes. Where are your pre-loads set front and rear? Pre-loads can change, even if so slightly, you bike's reactivity to input on the bars. More preload up front and less in the rear should make the bike less reactive. EG97 is thinking the same way, just more severe alteration. I tested the Uly again today several times from 75mph to 20mph. Perfectly straight with the bag frame on but the bags off. Like I stated before, I actually had head shake on the M2 even though it was slight. I came to the same conclusion that the engine rpms were related to the shake. When it happened on the M2 the bike was almost at idle in fifth gear. Where is your idle set at? I may pull the M2 back out and play with the idle and see if it effects the wiggles. This is like a puzzle I would love to find the answer to. I know you don't feel that way right? Last question and I post this to all. Has anyone else tried this test on a none Uly? Since in my case this problem did not affect the Uly but the M2, I was wondering if Eor has stumbled across a problem that is not just Uly related. |
Lowflyer
| Posted on Thursday, January 05, 2006 - 09:23 pm: |
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I can say that when I took the fairing off my Kaw and left the bags on, I got headshake at about 45-50 mph. I took the bags off; headshake went away. I am not smart enough to say why, but I think aerodynamics could be playing a part in the Uly shake. |
Blake
| Posted on Saturday, January 07, 2006 - 12:21 am: |
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It's the onset of a harmonic imbalance with the Coriolus effect. You obviously recieved one of the rare southern hemisphere Ulys by mistake. Try riding backwards and I bet you won't even notice the wobble. |
Wasions
| Posted on Saturday, January 07, 2006 - 01:20 am: |
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Heh. You may have something, there. Didja ever notice how slow-dancers (here in the U.S. of A.) invariably turn in a clockwise direction? Maybe Bindy can check to see if the opposite is true down south. Steve Gear up! |
Bindy
| Posted on Saturday, January 07, 2006 - 07:06 am: |
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Now I am shattered Blake here I was thinking Opto was a great little peddler, and the whole time those Jap bikes have been going backwards on purpose. Wasions Opto reckons he's off to get me a pole so I can check out your theory. |
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