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Calgary...
Posted: Sat Jul 12, 2008 11:05 pm
Guest
It was hiding at > 150 kph, deep into a right hand sweeper, over
slightly irregular asphalt, in a gusty cross wind.

It happened twice today, under almost exactly the same conditions.
After riding over a bit of wavy asphalt there was a slightly
disconcerting wobble in the Road King. Almost like the initial stages
of a tank slapper, but as long as I didn't put a death grip on the
bars and kept neutral on the throttle (neither accelerating or
decelerating) the bike seemed to track fine through the rest of the
corner and the wobble just faded away.

I have to say it was a very strange feeling.

Although not the first time the King has taken the same sweepers at
the same speed, it was the first time I encountered the wobble. Just
recently I played with the tire pressures and the air shocks. I went
to the high end of the acceptable range for both. Maybe that had
something to do with it.

I'll go back to the original setup and stay alert for the wobble. If
it persists I guess I'll have to look at one of the after market
remedies.


--
See Ya On The Road


2000 Yamaha Venture Millennium
2004 HD Road King
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Sean_Q_...
Posted: Sat Jul 12, 2008 11:48 pm
Guest
Calgary wrote:
Quote:
It was hiding at > 150 kph, deep into a right hand sweeper, over
slightly irregular asphalt, in a gusty cross wind.

It happened twice today, under almost exactly the same conditions.
After riding over a bit of wavy asphalt there was a slightly
disconcerting wobble in the Road King.

Excerpt from
http://www.harley-davidson-hangout.com/forum/hdrcgb-twin-cam-tc88-tc96/62519-stabilizers-2.html
---------------------------------------------------------------------
I've studied all these stabilizers in great depth for a while now.
They all do the same thing, which is to stop lateral movement of
the drive train, while still allowing vertical movement.

I'm a design engineer, that also has to manufacture the part that I
design. So I think I'm qualified to decide what's good and what's bad.
By far the best design is the TWR stabilizer.

Forget the Alloy Art stabilizer...it's what it says...art in alloy.
The geometry is completely wrong for it to be effective.

I've never liked the idea of a box assembly encasing the oil pan,
as with the True Trac and the others. It uses 4" stand off bolts to fit
the cage around the oil pan. This will have the ability to twist under
load, and it will. The leverage on the 1/4 UNC bolts can and probably
will cause it to fail at some point. A 1/4 UNC bolt was never designed
to have that much torque applied to it. And, I don't like the idea of 4
quarts of oil being dumped over my rear tyre if they did fail. The dog
bone mounting that goes into the frame crossmember is too far away and
because of this is also subjuect to a lot of stress, ie twisting.

I like the TWR setup, but I have found a weak point in that. It only
connects to the oil pan on the three rear bolts, why didn't they run it
round both corners and use up the available mounting points at the sides
as well. What I do like is that they have mounted the stress point
as close to the main casting as they can, which is a real good point
to have it....no tortional twisting can take place here. They run
the rod in to the side of the frame with as short a distance as possble.
This is good for strength.

What I don't like about any of them is the price. I can make a better
product than all of these at a fraction of the cost, and if it doesn't
work...I aint lost anything...just some of my time. I'll base it on
the TWR , but with a few design changes.

When it's done and tested on my Road King, which must be the worst
handling Harley ever built, and when I'm happy with it. I'll draw it all
up on CAD, and give it to any club member who wants to make their own. I
don't plan on producing it, so the drawings will be free to you if it's
for your own bike.

Another point I want to mention is that they are all made from
aluminium. This is not good, they need to be made from steel. The weight
isn't going to be much, it'll hardly notice.

We are conditioned to believe that Billet aluminium is good...we hear it
all the time. It's ok for dress up items, and engine cases, but not for
something that will be under this much stress. A billet is a solid block
of material that can and often is made from an assortment of crap grades
of melted down metal. Who knows how strong it really is. I doubt if
the manufacturers of these devices really know.

I'll let you know how I'm progressing as soon as I've started work
on it.

Brian.
---------------------------------------------------------------------

I had a Tru-track installed on my Ultra and I can't say if it's doing
any good because I haven't pushed my luck since then.

More on the True-track; seemed to work for this guy:
http://www.v-twinforum.com/forums/wheels-tires-suspensions/122886-stabilizer-bracket-kits-need-help.html

For a picture of the TWR stabilizer see:

http://kitchener.kijiji.ca/c-cars-vehicles-parts-accessories-HARLEY-DAVIDSON-TWR-REAR-STABILIZER-KIT-STOP-THAT-WOBBLE-W0QQAdIdZ35195345

SQ
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Thumper...
Posted: Sun Jul 13, 2008 12:27 am
Guest
"Sean_Q_" <nospam at (no spam) no.sapm> wrote in message
news:gOfek.75080$Jx.21911 at (no spam) pd7urf1no...
Quote:
Calgary wrote:
It was hiding at > 150 kph, deep into a right hand sweeper, over
slightly irregular asphalt, in a gusty cross wind.

snip


Yeah, I've have a Tru-Track stabilizer installed in my RK for several years.
Yawn. Seems fine for the sort of high speed curves I take on the Harley.
Never any issues of losing control or wrestling control. This bike is no
match for the BMW. I can easily take a curve at 80 mph on the RK as I can at
120 mph on the K1200GT. In fact the GT has much more room for faster. I
don't. However, since I've lost 76 lbs, there seems to be something strange
going on in the triple tree. If it were a Brit, I'd tighten it up a little.
I think my weight is further to the back of the bike now causing some
weirdness. I suppose, if I get the gumption, I'll put the stock bars back on
it. That will bring my body forward and provide better control.

BTW, It's amazing how much better and how much more fun and less fear Cat is
having on the Sportster since we took off the mini apes. We put new curved
risers on it and a narrower bar. he leans forward a little, but she says she
loves it. Sigh, I may have to do something similar with the RK.


--
"Of course, you'll have the good taste not to mention that I posted this."


Thumper


"I don't want a pickle..."

http://www.thumpers-roadhouse.ws


2006 H-D VRSCA V-Rod
2006 Buell XB12X Ulysees
2006 BMW K1200GT
2004 H-D FLHCRI Road King Classic
1979 Honda CBX
1978 Triumph T140V Bonneville
1975 Triumph T160 Trident
1974 Norton Commando Interstate
1969 BSA A75 Red Rocket III
1962 Triumph T20 Tiger Cub
1958 BSA Super Bantam COCK
1954 Velocette MAC




We'll see in the next service.

Both BMW and Buell handle surpurb at my lighter weight.


--
Rev. Thumper Rabbitt

Minister and Prophet,
Church of Rec.Motorcycles®.
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Robert Bolton...
Posted: Fri Jul 18, 2008 10:05 pm
Guest
On Sun, 13 Jul 2008 07:13:53 -0400, "Steve L" <srl1215 at (no spam) comcast.net>
wrote:

Quote:

"Thumper" <roadapple at (no spam) unclewebster.com> wrote in message
news:dr-dnYlfHY_ND-TVnZ2dnUVZ_vjinZ2d at (no spam) earthlink.com...

"Sean_Q_" <nospam at (no spam) no.sapm> wrote in message
news:gOfek.75080$Jx.21911 at (no spam) pd7urf1no...
Calgary wrote:
It was hiding at > 150 kph, deep into a right hand sweeper, over
slightly irregular asphalt, in a gusty cross wind.

snip

Yeah, I've have a Tru-Track stabilizer installed in my RK for several
years. Yawn. Seems fine for the sort of high speed curves I take on the
Harley. Never any issues of losing control or wrestling control. This bike
is no match for the BMW. I can easily take a curve at 80 mph on the RK as
I can at 120 mph on the K1200GT. In fact the GT has much more room for
faster. I don't. However, since I've lost 76 lbs, there seems to be
something strange going on in the triple tree. If it were a Brit, I'd
tighten it up a little. I think my weight is further to the back of the
bike now causing some weirdness. I suppose, if I get the gumption, I'll
put the stock bars back on it. That will bring my body forward and provide
better control.

BTW, It's amazing how much better and how much more fun and less fear Cat
is having on the Sportster since we took off the mini apes. We put new
curved risers on it and a narrower bar. he leans forward a little, but she
says she loves it. Sigh, I may have to do something similar with the RK.


--
"Of course, you'll have the good taste not to mention that I posted this."


Thumper


"I don't want a pickle..."

http://www.thumpers-roadhouse.ws


2006 H-D VRSCA V-Rod
2006 Buell XB12X Ulysees
2006 BMW K1200GT
2004 H-D FLHCRI Road King Classic
1979 Honda CBX
1978 Triumph T140V Bonneville
1975 Triumph T160 Trident
1974 Norton Commando Interstate
1969 BSA A75 Red Rocket III
1962 Triumph T20 Tiger Cub
1958 BSA Super Bantam COCK
1954 Velocette MAC




We'll see in the next service.

Both BMW and Buell handle surpurb at my lighter weight.


--
Rev. Thumper Rabbitt

Minister and Prophet,
Church of Rec.Motorcycles®.



I don't go too fast on my EGC (usually) and that seems to solve that issue
for me regarding the wobble, but I've been mid 80s in a sweeper and not
encountered it. But it is certainly not as rock-solid stabil as my Honda.

The leanin' forward thing is apparently what all the experts want us to do,
but it does hurt my lower back when doing some longer stretches in the
saddle. Makes sense we get more control that way.



Having seen the effect of replacing the soft springs on my Concours
with stiffer straight rate type, I assume the front end float of my
EGC is due to its soft suspension. I'm not that familiar with the
Harley yet, so perhaps it's something else.

Robert
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Road Glidin' Don...
Posted: Fri Jul 18, 2008 10:26 pm
Guest
On Sun, 13 Jul 2008 04:05:28 GMT, Calgary
<actual.rider_remove_the_obvious_ at (no spam) telus.net> wrote:

Quote:
It was hiding at > 150 kph, deep into a right hand sweeper, over
slightly irregular asphalt, in a gusty cross wind.

It happened twice today, under almost exactly the same conditions.
After riding over a bit of wavy asphalt there was a slightly
disconcerting wobble in the Road King. Almost like the initial stages
of a tank slapper, but as long as I didn't put a death grip on the
bars and kept neutral on the throttle (neither accelerating or
decelerating) the bike seemed to track fine through the rest of the
corner and the wobble just faded away.

I have to say it was a very strange feeling.

Although not the first time the King has taken the same sweepers at
the same speed, it was the first time I encountered the wobble. Just
recently I played with the tire pressures and the air shocks. I went
to the high end of the acceptable range for both. Maybe that had
something to do with it.

I'll go back to the original setup and stay alert for the wobble. If
it persists I guess I'll have to look at one of the after market
remedies.

Yikes. Never yet encountered it with my Road Glide. In fact, I'm not
sure I've heard of it with any Road Glide.

It would be interesting to try that same curve, at the same speed,
under the same conditions, sans your windshield...
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Bob Mann...
Posted: Sat Jul 19, 2008 11:58 pm
Guest
Calgary <actual.rider_remove_the_obvious_ at (no spam) telus.net> wrote in
news:q1l4849pqtggimjh5lasf8tb2rg9jktdeo at (no spam) 4ax.com:

Quote:
But the shield stays on. I like the wind protection and from what I
have read all of the touring models are susceptible to the wobble, bat
wings and all.


Especially the bat wings.
More sail to catch the wind.

--
Bob Mann

Cap'n, ah need moor pow'r.
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