If you have a loaded touring bike and you have a load stacked on top
of the rack and it's kind of floppy, then you can have stability
problems. Loose headsets or wimpy racks can also add to the problems.
It's not so much a problem with touring bikes per se,
but with flex in the system.
-Jeff Bell
In <5rlgnt$qko$1...@news.eecs.umich.edu> jlb...@presto.eecs.umich.edu
(Jeffrey L. Bell) writes:
>
>In article <33DE5C...@megsinet.net>, Mike <coa...@megsinet.net>
wrote:
>>I am looking into buying a toring bike and a local dealer told me
that
>>if you want to go fast don't buy a touring bike. He said that they
are
>>very unstable at speeds over 35mph. Is this true? I thought that a
>>longer wheelbase would be more stable than a short racing frame.
>
Mike <coa...@megsinet.net> wrote in article
<33DE5C...@megsinet.net>...
You really have to wonder sometimes where LBS' get people.
True touring bikes are stable to a fault. I've never ridden one over
35mph, but see no reason why it would be unstable. Maybe cheap bikes
are unstable over 35 mph. If you put heavy panniers or the front of a
bike it gets unstable at high speeds, but that has nothing to do with
it being a touring bike. Of course, cruising 35mph on a 80lb bike is
rarely a problem.
You might consider getting a sport frame with a triple for touring.
The only drawback is that you don't get the little holes in the fork
for mounting the low riders.
--
Morgan W. Jones - Current Network Technologies Corp.
Remove the "*nojunk*" from the mail address when replying
>I am looking into buying a toring bike and a local dealer told me that
>if you want to go fast don't buy a touring bike. He said that they are
>very unstable at speeds over 35mph. Is this true? I thought that a
>longer wheelbase would be more stable than a short racing frame.
Most likely, he never rode a touring bike at speed.
>I am looking into buying a toring bike and a local dealer told me that
>if you want to go fast don't buy a touring bike. He said that they are
>very unstable at speeds over 35mph. Is this true? I thought that a
>longer wheelbase would be more stable than a short racing frame.
Find another bike store, touring bikes can handle more straight line
speed than can by nervous system. Road bikes corner better because
they are inherently less stable.
Peter Gordon
Find another bike shop. I regularly took descents over 40 MPH on my
1984 Bianchi touring bike and had no stability problems. What more
expensive bike did the guy say you had to have?
--
Bob Gardali
gor...@best.com
> > I am looking into buying a toring bike and a local dealer told me
> that
> > if you want to go fast don't buy a touring bike. He said that they
> are
> > very unstable at speeds over 35mph. Is this true? I thought that a
> > longer wheelbase would be more stable than a short racing frame.
Joe Lucchio responded:
> Go to a different shop and talk to someone who knows something about
> touring bikes. This person is clueless. GENERALLY SPEAKING, a good
> touring bike will have more relaxed head and seat tube angles and a
> longer wheelbase which give a more stable ride, especially at speed.
> However, they are slower steering and have lower bottom brackets for
> stability while loaded, so they don't handle quite as quickly at
> speed.
I hope the Netiquette Police will overlook this infraction of the "me
too" rule, but I would like to add my voice to Joe's in this case.
"Clueless" is an understatement!
Sheldon "Going Down Hill Fast" Brown
Newtonville, Massachusetts
+----------------------------------------------------+
| The two most common elements in the Universe are |
| hydrogen and stupidity. --Harlan Ellison |
+----------------------------------------------------+
http://www.sheldonbrown.com/harris
Harris Cyclery, West Newton, Massachusetts
(617) 244-1040 FAX 244-1041
IMHO, this is incorrect. I've ridden my Cannondale touring bike
with lowrider panniers down Swiss passes at 80+ kmh (48 mph)
and it is dead stable. They actually are more stable because
they generally have a longer wheelbase brought about by
longer chainstays, slacker steerer angle, and more fork offset.
Also, the bottom bracket tends to be closer to the ground
than an American criterium-style race frame.
BTW, I ride my touring bike on medium-fast club rides
(average speeds 18mph over 80 miles). I have two seat post/seat
combinations: one with my leather touring saddle and saddle
bag (heavy) and one with a Vetta turbo racing saddle (light).
I have a set of touring wheels/tires and a set of "go fast"
wheels/tires. I can install/remove my fenders in 4 minutes because
I use wing nuts. So, in the end I only need one bike!
The weight difference between "touring" and "racing" configuration
is about 10 lbs (15 kilograms versus 10.5 kilos).
Rob.
I would not say touring bikes are inherently unstable, but would
caution riders on loaded touring bikes to pack them carefully.
That is, with panniers on both the front and back. I have
experienced a lateral shimmy when riding a loaded touring bike
carrying all the load on the rear wheel. It was easily corrected
by the addition of smaller front panniers.
I'm araid I'm going to have to come down on the wobbly side of
this argument.
I ride a 25" frame and find that most touring bikes with their
long wheelbases and standard sized tubing _are_ speed wobblers
over 30 mph or so.
I think that some touring bikes are stable (I do have a Raleigh
Kodiak with oversized tubing that is stable at speed) but most
touring bikes are meant to ride 'slowly' and loaded and not much
thought is given to stability.
Maybe someone can enlighten me, but I don't see how it could be any more
unstable than a SWB road racing bike. Did he happen to try and sell you a
nice, shinny M2 road bike for twice the price?
___________________________________________
Chris Phillipo - webm...@tread.pair.com
TREAD Publications - TREAD Online! Cycle Magazine.
http://www.tread.pair.com/ - http://www.tread.pair.com/bikemag/
>I am looking into buying a toring bike and a local dealer told me that
>if you want to go fast don't buy a touring bike. He said that they are
>very unstable at speeds over 35mph. Is this true? I thought that a
>longer wheelbase would be more stable than a short racing frame.
They're a little sluggish in the corners, but in a straight line at high
speed they are quite stable.
--
Mike DeMicco <dem...@value.net>
My Miyata touring bike is rock stable up to at least 50 mph ...
downhill of course :-)
Kerry Kunsman
Or the store doesn't carry touring bikes.
I can't believe that a dealer told you this unless he was overstocked
with mountain bikes.
The steering geometry, combined with the larger wheel diameter, of a
touring bike, dictates that it be more stable at speed, though the
corollary to that is that it will be less nimble in handling.
Paul Harris
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
WORD WORKS TECHNICAL COMMUNICATIONS
Design & Layout
Digital Typesetting (250)384-3076
Editing & Writing (250)384-4402 (fax)
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Victoria, BC V8V 2W8 P.Ha...@WordWorks.bc.ca
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Some bikes have very high lateral stiffness,
which eliminates "speed wobble" or "shimmy" at high speed.
All Cannondale road bikes, touring or racing, are very
stiff laterally. No bottom bracket flex, no shimmy.
Other bikes are prone to shimmy. Whether touring
bikes are more prone to shimmy than racing bikes of the
same quality is a question I'll leave to others.
Conclusion: Get a Cannondale touring bike and you
won't have to worry about high speed stability. Just dents :)!
Actually, the preferred arrangement is the smaller panniers on the
rear, larger ones up front on lowriders. Makes a difference.
Tim
For what it is worth:
I was reading a poster in the Physics Hall the other day. It
said that the 'trail' of your front fork (defined as the length
of ground between a line drawn from your front hub to the ground
and a line drawn in the same direction the fork is pointing at the
point it is attached to the wheel's hub.) has a lot to do with
stability of a bike.
If your front fork is swept forward (as I assume touring bikes
are...btw, could someone mail me to tell me the difference betw.
a touring bike and a regular old road bike?...thanks) your
trail is short...this means that you are sacrificing stability
for better handling. (ability to make more agile turns, I assume)
However, on some mountain bike I have seen the fork's entire
length is perfectly straight. This design allows for a longer
'trail', thus allows for greater stability. Thus, if you are
really worried (or really do have a trouble) about touring bike
instability at high speeds, swap out the fork.
Hope this helps.
Mike
>If your front fork is swept forward (as I assume touring bikes
>are...btw, could someone mail me to tell me the difference betw.
>a touring bike and a regular old road bike?...thanks) your
>trail is short...this means that you are sacrificing stability
>for better handling. (ability to make more agile turns, I assume)
Most "touring bikes" that I've seen had a generous fork rake and a
long(er) rear triangle. This, combined with low frame angles, results
in a longer wheelbase overall. The longer rear triangle permits
mounting fenders and panniers on the rear without interfering with the
rider's heel. In addition, they usually have numerous attachment
points (eyelets, etc) on the frame to mount racks, panniers, fenders,
etc. They normally include mounting points for several water bottles.
Some touring bikes have beefed-up brakes and many have triple
chainrings in front (with related longer BB axle.)
Older (and present) road bikes almost never have eyelets or mounting
points but 2 water-bottle braze-ons are now pretty much the norm. The
rear triangles are shorter -- usually little or no fender clearance.
Frame angles are steeper. 2 chainrings are the norm. The fork rake
may be shorter, but probably not "straight".
>However, on some mountain bike I have seen the fork's entire
>length is perfectly straight. This design allows for a longer
>'trail', thus allows for greater stability. Thus, if you are
>really worried (or really do have a trouble) about touring bike
>instability at high speeds, swap out the fork.
A well designed touring bike will be plenty stable at speed.
Actually, any well designed bike should be stable at speed.
..........dh
> Jeffrey L. Bell wrote:
> For what it is worth:
>
> If your front fork is swept forward (as I assume touring bikes
> are...btw, could someone mail me to tell me the difference betw.
> a touring bike and a regular old road bike?...thanks) your
> trail is short...this means that you are sacrificing stability
> for better handling. (ability to make more agile turns, I assume)
>
> However, on some mountain bike I have seen the fork's entire
> length is perfectly straight. This design allows for a longer
> 'trail', thus allows for greater stability. Thus, if you are
> really worried (or really do have a trouble) about touring bike
> instability at high speeds, swap out the fork.
Was the poster signed "Aristotle", by chance?
In fact, I ride ride this beast every day to from work and rarely
get a day that I don't do at least 34MPH, most of the time its
because of the weather or the petrol burners in the way.
I think the instability problems are:
* low-riders and/or handlebar bags affect your steering some.
* extra weight in panniers or on rear rack won't lean with your
body taking away some of your body english .
Of course everyone regardless if it is a touring bike or not would
have problems with:
* flexy forks that steer the bike themselves
* mis-adjusted headsets that lets the front wheel flop about some.
* a frame that flexes some and you just happen to run over a rough
road just at the speed that you hit a resonance point and the bike
becomes a tuning fork.
* soft tires that have their own resonance (more up and down than
side to side)
* and finally poor brakes/tires/judgement that doesn't allow you to
pass by or stop safely when going fast.
Adam Zilinskas
a...@synario.com
http://www.data-io.com/~aez/
end
>Mike:
>>If your front fork is swept forward (as I assume touring bikes
>>are...btw, could someone mail me to tell me the difference betw.
>>a touring bike and a regular old road bike?...thanks) your
>>trail is short...this means that you are sacrificing stability
>>for better handling. (ability to make more agile turns, I assume)
>Most "touring bikes" that I've seen had a generous fork rake and a
>long(er) rear triangle.
I've never seen a touring bike without fork offset, either at
the crown or by raking the blades. (For that matter, I've seen
very few bikes of any kind without significant fork offset.
Those mountain bike suspension forks and faddish straight-bladed
road forks just have the offset built into the crown instead of
bent into the blades.) A fork without any offset would give
terrible handling on a standard-geometry frame, and would also
cause serious fender/downtube overlap on many frames, which is a
lot harder to work around than fender/toe clip overlap.
The relevant question is the trail that results from both the
steering angle and the amount of fork offset. For a given head
tube angle, more rake == less trail. But the lower head tube
angles of most touring bikes allow both plenty of rake for a long
wheelbase and plenty of trail for stable handling. A loaded
touring bike may well have both more fork rake and more trail
than a racing bike thanks to its slack head tube angle.
(For more on rake & trail, see the explanation and illustration
at http://www.wolfenet.com/~josh/bike/trail.html)
--
Jo...@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013
"My other bike is a car."
http://www.wolfenet.com/~josh
>I'm araid I'm going to have to come down on the wobbly side of
>this argument.
>I ride a 25" frame and find that most touring bikes with their
>long wheelbases and standard sized tubing _are_ speed wobblers
>over 30 mph or so.
I think this may be more true of light touring bikes that have
touring geometry but racing-weight tubes. A proper touring bike
will have heavier tubes, especially the top and down tubes, e.g.
531 Competition has a 0.8/0.5 top tube, while 531 Super Tourist
has a 1.0/0.7 top tube.
>I think that some touring bikes are stable (I do have a Raleigh
>Kodiak with oversized tubing that is stable at speed) but most
>touring bikes are meant to ride 'slowly' and loaded and not much
>thought is given to stability.
I've never owned a touring bike myself that wasn't rock-steady
descending mountains at 50mph with a full touring load, but I
have seen other riders develop terrible steering shimmy at much
slower speeds.
The geometry of touring bikes is definitely designed for
stability, but proper materials are needed, too.
Mike;
MTBs with 'straight' forks still have fork rake. Straight rigid forks simply
have an angle at the crown joint instead of curved tubes. Suspension forks mount
the wheel on a forward offset from the shock tube. At any rate the contact point
of a bicycle tire is *behind* the steerer tube axis. Thus more rake reduces trail.
-regards
John Getsoian
[jget...@compuserve.com
or sls...@umich.edu]
Josh wrote:
>I've never seen a touring bike without fork offset, either at
>the crown or by raking the blades. (For that matter, I've seen
>very few bikes of any kind without significant fork offset.
>Those mountain bike suspension forks and faddish straight-bladed
>road forks just have the offset built into the crown instead of
>bent into the blades.) A fork without any offset would give
>terrible handling on a standard-geometry frame, and would also
>cause serious fender/downtube overlap on many frames, which is a
>lot harder to work around than fender/toe clip overlap.
>The relevant question is the trail that results from both the
>steering angle and the amount of fork offset. For a given head
>tube angle, more rake == less trail. But the lower head tube
>angles of most touring bikes allow both plenty of rake for a long
>wheelbase and plenty of trail for stable handling. A loaded
>touring bike may well have both more fork rake and more trail
>than a racing bike thanks to its slack head tube angle.
What he said! Josh, extremely well said! I was contemplating how to write
this in a response, but then I read yours. I agree on all points. It's
really funny how many people think that mountain bike forks don't have rake.
Hopefully traditional road bikes will never imitate this style - it's very
ugly! (yes there are already 'road' bikes with straight-bladed forks, and
they look like crap).
Rich
> For what it is worth:
>
> ...the 'trail' of your front fork (defined as the length
> of ground between a line drawn from your front hub to the ground
> and a line drawn in the same direction the fork is pointing at the
> point it is attached to the wheel's hub.) has a lot to do with
> stability of a bike.
This is true.
> If your front fork is swept forward (as I assume touring bikes
> are...btw, could someone mail me to tell me the difference betw.
> a touring bike and a regular old road bike?...thanks)
See: my Glossary entry on this subject:
http://www.sheldonbrown.com/gloss_ta-o.html#touringbike
> your
> trail is short...this means that you are sacrificing stability
> for better handling. (ability to make more agile turns, I assume)
>
> However, on some mountain bike I have seen the fork's entire
> length is perfectly straight. This design allows for a longer
> 'trail', thus allows for greater stability. Thus, if you are
> really worried (or really do have a trouble) about touring bike
> instability at high speeds, swap out the fork.
>
> Hope this helps.
I'm afraid it doesn't. The trail, for a given wheel size, is determined
by the "rake" or "offset" (forward sweep) of the fork, _and_also_ by the
angle of the steering axis. Looking at one or the other of these
parameters without considering the other one is confusing and
meaningless.
Although touring bikes usually have more rake than racers, they also
have a less upright head angle, so they typically have more trail.
Forks which appear straight actually have rake too, it is just that the
straight blades slope forward from the steering axis. The basic
geometry is not different from that of similar bikes with curved fork
blades.
Swapping out the fork in an attempt to improve a bike's riding
characteristics is poor advice. The vast majority of bicycles come with
forks that are designed to work properly with the head angle of the
frame, and installing a fork with radically different rake will usually
cause a deterioration in the handling.
Some other posters in this thread have spoken of issues of speed
wobble. This is not a characteristic to which touring _bikes_ are more
prone than other types of bikes are, but touring _loads_, improperly
stowed, are often at fault.
In the case of un-loaded bikes with speed wobble, the problem is very
rarely related to the frame geometry or construction. In most cases it
is the result of substandard wheels: either out of true, or with
insufficient spoke tension.
Sheldon "Rakish" Brown
Newtonville, Massachusetts
+---------------------------------------+
| The cure for boredom is curiosity. |
| There is no cure for curiosity. |
| -- Ellen Parr |
+---------------------------------------+
Robert Perkins <no_spam_...@nortel.ca> wrote in article
<33DF24...@nortel.ca>...