Subject: Re: high speed instability
Author: Alan Dunphy
Date: May 31, 2002, 8:35 PM
Post ID: 1710356195
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I had a high speed wobble on my brand new 76 Yamaha tripple some wear in excess of 100 mph, I really wasn't looking at the meter at that speed (I don't go that fast any more). It turned out to be an after market windshield that was not quite perfectly straight. None of my Eldorados or Ambassador has shown the tendency to high speed wobble, only some head shake on take off. I installed a new stock steering damper on the 1st Eldo and it solved the head shake. Note that these dampers do wear out over time so check them occasionally. My brother purchased my first Eldorado and sent it out for restoration. He experienced a high speed wobble at around 75 mph after he got it back. The damper showed no resistance when removed and has since been replaced. I suspect that any of the loops we now run would have wobbled by now if the frame had problems. I would first check that anything mounted on the forks was truly symmetrical such as windshields, fairings, lights, and horns, etc. Next I would check the wheel alignment front to back and make sure that all spacers and washers were properly installed on the axles. After that I would try to load the bike evenly when traveling. If it still wobbled I would then be baffled. I have been told the proper way to handle a wobble is to 1 roll off the throttle 2 put as much weight as far forward as possible ( I laid on the tank on the Yamaha) 3 relax your grip on the bars. Do not grab the brakes. Some say to get on the rear brake very lightly, I don;'t know about linked brakes, I guess I wouldn't touch them. I was lucky as I was on the interstate and had two lanes and shoulder to play with while regaining control, used most of it, Too.
Alan
'74 Eldorado LAPD Wixomized
MGNOC 4352
Alan R. Dunphy
adun-@midmaine.com
21 West ST.
Pittsfield, ME 04967-1426
PS....I had Dunlops on all but the present, and they are comming as soon as I can on this one.
----- Original Message -----
From: scott kelso
To: Loopfram-@topica.com
Sent: Friday, May 31, 2002 3:53 PM
Subject: high speed instability
I would like to know if any list members have experienced the infamous high speed wobble on their loopframes and would be willing to share this experience with the group.My eldo is currently shod with Conti Blitz tires,and sports wixom bags,trunk and Bates 700 fairing.I have ridden the bike at an indicated 90mph with no hint of instability,although i can feel a little bobble in the rear tire when crossing over painted lines on the highway at high speed.Im wondering if the reported episodes of instability are a sudden event or are they caused by a dynamic set in motion by a rear wheel bobble such as i feel on my bike when passing slow moving vehicles on the highway.Would appreciate any info.Next weekend at Gunstock Ski resort there is a vintage bike show&swap meet on Sat.,vintage roadrace on Sun.,and an awesome hillclimb event on Wed.Check out www.gunstock.com for info.Hope to see more than than one loopeframe there this year.Will post pics in a couple weeks.Thanks Scott K.
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<DIV><FONT face="Times New Roman">I had a high speed wobble on my brand new 76
Yamaha tripple some wear in excess of 100 mph, I really wasn't looking at the
meter at that speed (I don't go that fast any more). It turned out to be an
after market windshield that was not quite perfectly straight. None of my
Eldorados or Ambassador has shown the tendency to high speed wobble, only some
head shake on take off. I installed a new stock steering damper on the 1st
Eldo and it solved the head shake. Note that these dampers do wear out over time
so check them occasionally. My brother purchased my first Eldorado and sent it
out for restoration. He experienced a high speed wobble at around 75 mph after
he got it back. The damper showed no resistance when removed and has since been
replaced. I suspect that any of the loops we now run would have wobbled by now
if the frame had problems. I would first check that anything mounted on the
forks was truly symmetrical such as windshields, fairings, lights, and horns,
etc. Next I would check the wheel alignment front to back and make sure that all
spacers and washers were properly installed on the axles. After that I would try
to load the bike evenly when traveling. If it still wobbled I would then be
baffled. I have been told the proper way to handle a wobble is to 1
roll off the throttle 2 put as much weight as far forward as possible (
I laid on the tank on the Yamaha) 3 relax your grip on the bars. Do
not grab the brakes. Some say to get on the rear brake very lightly, I
don;'t know about linked brakes, I guess I wouldn't touch them. I was lucky as I
was on the interstate and had two lanes and shoulder to play with
while regaining control, used most of it, Too.</FONT></DIV>
<DIV><FONT face="Times New Roman"></FONT> </DIV>
<DIV>Alan<BR>'74 Eldorado LAPD Wixomized<BR>MGNOC 4352<BR><BR>Alan R.
Dunphy<BR><A href="mailto:adun-@midmaine.com">adun-@midmaine.com</A><BR>21
West ST.<BR>Pittsfield, ME 04967-1426<BR><BR><FONT
face="Times New Roman">PS....I had Dunlops on all but the present, and they are
comming as soon as I can on this one.</FONT></DIV>
<DIV> </DIV>
<DIV> </DIV>
<BLOCKQUOTE dir=ltr
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=fo-@conknet.com href="mailto:fores-@conknet.com">scott
kelso</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=Loopf-@topica.com
href="mailto:Loopfram-@topica.com">Loopfram-@topica.com</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, May 31, 2002 3:53 PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> high speed instability</DIV>
<DIV><BR></DIV>
<DIV><FONT size=2>I would like to know if any list members have experienced
the infamous high speed wobble on their loopframes and would be willing to
share this experience with the group.My eldo is currently shod with Conti
Blitz tires,and sports wixom bags,trunk and Bates 700 fairing.I have ridden
the bike at an indicated 90mph with no hint of instability,although i can feel
a little bobble in the rear tire when crossing over painted lines on the
highway at high speed.Im wondering if the reported episodes of instability are
a sudden event or are they caused by a dynamic set in motion by a rear wheel
bobble such as i feel on my bike when passing slow moving vehicles on the
highway.Would appreciate any info.Next weekend at Gunstock Ski resort there is
a vintage bike show&swap meet on Sat.,vintage roadrace on Sun.,and an
awesome hillclimb event on Wed.Check out <A
href="http://www.gunstock.com">www.gunstock.com</A> for info.Hope to see more
than than one loopeframe there this year.Will post pics in a couple
weeks.Thanks Scott K.</FONT></DIV></BLOCKQUOTE>
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