| Buyers Guide - More Detail |
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This section is rather lengthy
but if you would like to know more about the Trice
then please read on.
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Seat
Ergonomics The seat on a recumbent trike is the main contact between
the rider and the machine. This makes the design of
the seat one of the most important aspects of the whole
trike. Trice seats can be quickly and easily
removed from the frame and all models have at least
15 degrees of angle adjustment, essential, if you are
going to get the most out of a recumbent.
Fabric
Seat
Our fabric seat has a durable woven-mesh cover
stretched over an aluminium frame, which is TIG welded
and powder-coated. The seat rails allow a number of
ICE accessories to be fastened to the seat. The frame
is bent to give the seat its shape including a lumbar
support important for long term comfort and a kick for
the shoulders which helps to support your head. The
cover is reinforced to allow the 14 straps to be adjusted
independently, to suit the shape of your back perfectly.
The fabric has just enough stretch to allow for belts
or seams in clothing. This 'give' in the fabric also
provides support to keep your upper body centred on
the seat, but still allows you to lean out in the turns. Riding comfort is
further enhanced by the option of a reticulated foam
cushion under the seat base. This foam is highly breathable
and retains very little water if it gets wet. With an
adjustable neck rest available for this seat it is well
suited to a wide range of riders. People find it comfortable
from the first moment they sit on it.
Hard
Shell Seat
We offer the option of a hard-shell moulded composite
seat. Designed primarily as a performance seat. It is
intended to be more reclined than the fabric seat. The
further you recline the seat the more aerodynamic you
are so you go faster for the same effort. Our seat shape fits a large range of sizes
of people. It can also be fitted with an adjustable neck rest,
which does not interfere with a helmet. The seat has
a pronounced lumbar support that helps locate your pelvis
for efficient power transfer to the pedals, particularly
important for hill climbing. The adjustable side wings of the
seat keep you in place when cornering hard. The
shape still allows you to easily lean
out in a corner if the need arises. The seat stiffness
maximises the amount of power going into the drivetrain
enhancing the performance of the Trice.
The seat is fitted
with a custom made highly breathable cover while still enjoying the
benefits of excellent power transmission and firm support.
Steering
We design the steering for each of our models individually
at the time the machine is first drawn. We do not blindly
transplant the steering from one model to another, as
this is the recipe for mediocre handling and performance.
After the prototype of each model is made, it is tested
and pressed hard to see how the handling could be improved.
There is no such thing as a machine that is perfect
straight off the drawing board, and every trike can
benefit from minor tuning to the steering geometry at
this stage. As the steering becomes more and more refined,
we are able to push the trike harder and closer to its
limits (occasionally past it's limits, but better us
than the customer!)
The way Trice handle at speed is of premier importance
to us at ICE. Even if you have no intention of pushing
your Trice to its limits, you may on occasion find yourself
going faster than you intended down a hill and you don't
want the machine to feel unsafe. One aspect of the design
which influences the feel of a trike at speed is the
rate at which turning the handelbars turns the front
wheels, this also influences the turning circle. These
two, feel at speed and turning circle are inextricably
linked. A trike with a small turning circle will feel
dangerously twitchy at speed, a trike that feels super
steady at speed will have a large turning circle. A
small turning circle can be useful on occasion but,
as long as the trike can do a 'U' turn on an average
width road and safely negotiate any road junction, we
consider the turning circle to be small enough.
This is how we set up Trice steering, the turning circle
is small enough to be practical and the feeling at speed
is safe and sure. All our trikes are designed with Ackerman
steering. Ackerman steering is an arrangement where
the wheel on the outside of a curve turns at a smaller
angle than the wheel on the inside of the curve. The
reason for this is that the inside wheel turns on a
smaller circle than the outside wheel.
Brakes
The braking on a tricycle is very different from braking
on a 2-wheeled upright. With a Trice, two front wheels
are doing the braking and your centre of gravity is
much lower, you can stop much quicker and you don't
have to put a foot down when you stop. When you apply
the brakes your weight shifts forward on to the front
wheels. No useful braking force can be applied to the
rear wheel unless the Trice is heavily loaded. We fit
cable-operated drum brakes as standard on the front
wheels (with a hydraulic disc brake option). A cable operated system is very simple and can
be maintained easily and inexpensively. Hydraulic systems
do give more braking power, but they are far more complicated
and costly. One of the main advantages of hydraulics
is the efficient transfer of power along long and circuitous
cable routing. The short connection between the brake
levers and the front brakes on a Trice make this a non-issue.
We test our machines in the real world. Our premises
are in Cornwall in the UK, a very hilly part of the
country. Our machines are designed and built to handle
these challenging conditions. There is not one machine
in our range that we would not hesitate to take down
our local testing hill at speeds touching 50 mph. This
hill has a roundabout at the bottom and a sharp left
turn leading over a grating to a bike path.
No
brake steer
Brake steer is commonly known as the effect that applying
the brakes can have on the steering. If both front brakes
are mechanically linked (operate together) then in theory
the trike should stop in a straight line. Unfortunately
it is very difficult to make it work consistently well
particularly with powerful brakes like discs. Factors
such as cable friction, pad friction, road surface friction,
tyre pressure etc. all contribute to make a linked system
unbalanced. So Trice are set up with their front brakes
operating independently of each other. The left lever
operates the left brake and the right the right.
This is done for a number of reasons:-
1, With two hands
operating two brakes you can brake twice as hard as
with one hand operating two brakes. If one of the brakes
fails mechanically for some reason it is vital that
the trike can still be brought to a stop quickly and
safely.
2, During braking on a trike it is quite common
to find that one front wheel has greater grip on the
road surface than the other, due to cornering forces,
wet patches, uneven tarmac surface, debris from a bovine
source, etc.. With independent front brakes you can
easily adjust the braking force applied to each wheel
to make best use of the grip available.
3, Easy maintenance
and adjustment.
How
we test for brake steer
When we first developed the idea of how to eliminate
brake steer on a recumbent trike, we had to come up
with a method of testing our ideas. There are a number
of ways that a rider can unconsciously affect the handling
of a trike, and these inputs had to be eliminated if
we were to see how effective our solutions were. The
final arrangement was simply this: Remove the brake
lever from the handlebar and attach it to a short length
of tubing. Replace the brake cable with a longer length
so the rider could hold the lever comfortably against
his body and away from the steering. The rider then
rode the trike downhill. Letting go of the handlebars
(so there was no rider influence on the steering) the
brake lever was applied. A machine with no brake steer
will come to a stop in a straight line, even with only
one brake operating. Every Trice will pass this test!
How
it affects handling under braking
Our No-Brake Steer geometry is not centrepoint steering.
Centrepoint steering is when the axis of the kingpost
passes through the centre of the contact patch of the
tyre. In theory, this should result in completely neutral
steering. In practice, the forces acting on the tyre
and the steering are many and vary quickly as the machine
is steered. Centrepoint geometry, while better than
some possible arrangements, does not result in neutral
steering and does lead to brake steer.
Another aspect of steering geometry that should be considered
is bump steer. With trikes, bump steer is caused by
the wheel hitting an obstacle on the road (potholes
or stones) and having the resulting forces work to turn
the steering wheels. The steering geometry that promotes
bump steer is exactly the same that creates brake steer;
sorting out the steering geometry will alleviate both
conditions.
An added advantage of our steering geometry is the improved
handling in corners. Poor steering geometry can affect
handling when pushing the trike hard thorough a corner.
The steering will load up (feel heavier); possibly to
the point where the rider no longer has the power to
counteract it. In these instances, the preferable way
of negotiating the corner is use brake steering to your
advantage. Braking on the inside wheel will pull that
wheel in the correct direction, and steer the trike
through the corner. This is not good for the tyre and
it scrubs off speed. Designers can reduce the loading
effect by steepening the caster angle (the angle the
kingpost makes with the ground). This lightens the steering
through the corner, but makes the trike twitchy in a
straight line. Our No-Brake Steer geometry eliminates
this loading up of the steering through fast corners.
This means that the rider can steer around a corner
at speed without resorting to using the brakes for help.
Trice steering just provides the rider with a gentle
feedback to help sense what the wheels are doing. Eliminating
the bad handling in the corners allows us to design
the caster angle for the optimum steering characteristics
we want from the trike. We don't have to use the caster
angle to compensate for bad design in other areas of
the steering geometry. The net effect is one that many
of our customers describe as "power steering".
Braking
hard in a tight corner
If you need to slow quickly during a high speed corner
as you go for example, around a left hand bend, the
right front wheel will become heavily loaded and the
left front wheel could even lift off a little. In this
situation, only the right wheel will be effective in
stopping you. If the trikes steering geometry causes
brake steer, then by applying the brakes (whether or
not the brakes are linked) you would feel the steering
pulling to the right out of the left hand corner. This
is very undesirable. This will not happen when you ride
a Trice. you can brake safely in a corner without any
noticeable pull on the steering trying to change your
line.
Track
Our machines come in a variety of track widths. Choosing
a track width is a matter of looking at your needs and
abilities and choosing what is appropriate. The first
issue is not track width, but rider width. A larger rider will not find the narrower
machines comfortable and they may not be able to move
the steering to its extremes. On the other side of the
coin, there is no sense in the smaller rider choosing
a standard track machine; it is simply bigger than needed
unless maximum stability is the priority. Track width
can make a small difference in moving the machine around.
A narrow machine can move through doors and width-restricted
bike paths much more easily. They are slightly lighter
and easier to lift and store. Track width also affects
stability. The wider the track, the more stable the
machine. Stability, however, is not only determined
by track width. Seat height has a major effect and wider
tracks are better suited to machines with a higher seat.
The rider's riding style also plays a major role.
Frame
A trike is not able to lean the same way that a bicycle
can, this imposes considerable loads on the frame. The
recumbent seating position also increases loads on the
frame, as the rider is not able to lift themselves off
the machine while going over bumps and rough roads.
Because of this increased loading, particular care must
be taken over the design of the joints. The joints that
can be problem areas are the main crossaxle/main spar
connection, and the front seat mounting. The ideal joint
needs to be well sized, with large, tapering contact
areas that distribute the loads smoothly over the tubes.
This is the reason why traditional bicycle building
has developed lugged joints as the best way of joining
lightweight tubing. The lug can be designed to spread
the loads over a generous area, eliminating the hard
spots that can concentrate stress and lead to failure.
ICE trikes use custom laser-cut lugs at all critical
joints. These lugs are hand-brazed to the tubes. Brazing
is the traditional method framemakers have used for
joining tube since the days of the high-wheeler. A proper
brazed joint is as strong or stronger than the metal
it is joining. The smooth profile of the brazed joint
spreads the loads evenly across the joint. The bronze
filler material will run under and around the joint,
so the joined area of metal is usually greater than
can be seen on the surface.
Materials
Trice are built from a combination of Cro Mo steel tube and heat treated Aluminium.
Fatigue
strength and number of cycles to failure
One characteristic of all steels is that if the loads
are kept below a certain point, the "fatigue limit",
the material can be flexed a virtually unlimited number
of times. Making it an ideal material for a Trike frame
which has to absorb low frequency, high load flexing
(from pedaling) and high frequency, low load vibration
(from the road surface). Non-ferrous metals, such as
aluminium, do not have a fatigue limit; they will fail
if flexed enough times. The more often the aluminium
is flexed, the lower the load it can stand. Where Aluminium
works particularly well however is in making parts that
are extremely stiff, its low density allows designers
to increase the wall thickness of the metal in a part
to maximise stiffness without making that part too heavy.
For these reasons, we use a mixture of materials to build our frames and steering
components.
Stiffness
Altering a number of factors can vary the stiffness
of a trike frame. Tube diameter and tube wall thickness
are the main factors; tube material and frame design
can also play a part. The practical application of this
for recumbent trike frames is that stiffness cannot
be gained without increasing the weight of the machine,
and frame weight cannot be easily reduced without compromising
stiffness. Stiffness in the frame is also important
for power transmission. The long chain runs between
the chainrings and the rear wheel can cause frame flex
with every pedal stroke if the chain runs are not properly
thought out.
Ride
quality
It would be an easy task for the trike designer if all
they had to do were try to create the stiffest possible
trike. However, stiffness also influences ride quality.
It is desirable to build in an amount of controlled
flex to the main frame to help absorb road shock and vibration.
The frame flex designed into a Trice provides you with
a softer ride without compromising performance or the
frames longevity.
Top
of Page
Power
transmission
The best transmission is one that is direct from chainring
to cassette, without any bends, idlers or complications.
For most recumbents, this would require passing the
chain through the rider's body. We are left with little
choice (other than radical surgery) but to run the chain
along the frame and under the seat. This will require
the use of one idler pulley mounted somewhere below
and ahead of the seat. Placement will also consider
clearances to the crossaxle and how the chain runs through
the rear frame. The chain can usually be managed
by one idler only.
The drivetrain does not necessarily have to suffer for
having these idlers. If the chain angles are kept as
shallow as possible the friction losses are kept to
a minimum. Trice are fitted with Polyurethane idlers
because they are very quiet, smooth running and have
a long life.
Gear
range
Recumbents have different gearing requirements from
upright bikes. Not being able to pedal out of the saddle
means that the gearing range has to be increased on
the lower end so that you can winch your way up steep
hills. The improved aerodynamics of the recumbent position
makes higher gears useful. Hub gears are often avoided
by cyclists because they are less efficient than derailleur
gears.
Aesthetics
Life is too short to settle for ugly. Here at ICE aesthetics
are an integral part of the design process. There is
no need for ugly design, and it costs little more to
create something that is functional and beautiful.
Adjustability
The essential adjustments are for leg length, body angle,
and handlebar position. Seat Angle - finding a seat
angle that suits you is usually a matter of making small
adjustments and riding the machine for a few miles to
see how it feels. All Trice have adjustable seat angles,
giving you the advantage of being able to set your trike
up just the way you like it. Leg Length - essentially
the same adjustment as you would make if you were riding
a diamond-frame bike, but with an important difference.
Weight distribution on a recumbent is determined mainly
by the seat position, and using a moving seat to adjust
for leg length would alter the way the trike handles.
Trice have an adjustable section built into the frame
to allow the distance from the seat to the pedals to
be set to your requirements. Handlebar Position. - important
if you think about what the handlebars do. They not
only steer the trike, but also provide an element of
support to the rider when cornering. Finding the best
place to put the handlebars is a matter of personal
taste. The length of the rider's torso, arms, and the
width of the rider's waist and shoulders will determine
the final position. On all Trice, the handlebars are
made from aluminium
and anodised.
They are adjustable in width, and fore-and-aft position.
They are easily replaced should they get damaged.
Accessories
and options
A trike is not just a trike. People have individual
needs and their trikes tend to reflect their riding
preferences. It is for this reason that ICE offers a
broad range of accessories that let you tailor your
trike to meet your needs. We put the same attention
to detail into our accessories that we do into the trikes
they are made for.
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