No. 2 November - December 2003
View from "Five Ways" on the road up
Mt Dandenong, near Ferntree Gully.
|During the last two months we have
been busy with shows in both Australia and the USA. These shows
require quite a lot of preparation, as well as time away from the
office and the factory. However they give us the opportunity of
meeting face to face with dealers and customers, and enable us to
gather valuable feedback on our trikes and our service. Also
coming up this month is the annual Maryborough Pedal Prix where
over 150 school teams compete in a 24 hr race,
scoring points for construction, design, and presentation, as well
as race results. So this is a busy time of the year for us, as we
head towards Christmas and our summer holidays. We will be taking
two weeks off over Christmas, knocking off on Friday the 19th
December, and resuming on Monday 6th January 2004.
Ian Sims, November 2003
- New Headrests
- New Tandem Stoker Handle Bars
- GS Options - The Rohloff
- GS Options - The Schlumpf
- Christmas deliveries
1. New Headrests
The main feature of any recumbent is the reclined seating
position. This position both reduces the wind resistance, making
the machine more efficient than an upright bike, and also makes it
more comfortable, as there is less weight on your backside. In
fact the more reclined the seat, the faster the machine. This why
our Touring Trikes have a 40 degree seat, whereas our Race Trikes
have a 20 degree seat.
However a few riders have found that even with a 40 degree seat
they seem to be holding their heads forward, and they find this
uncomfortable. Usually this disappears after a couple of hundred
miles, as the neck muscles adjust. If after a couple of months it
is still a problem, then we now have a new headrest. Unlike the
old head rests, which were just an extension of the seat, with a
small sub-frame and extra seat material, the new head rests are
adjustable both up and down, and fore and aft. Furthermore they
cause less air drag than the old headrests, and fit both the
standard seats and the wide seats.
As the headrest interferes with flag posts in the existing
holders, new flag holders are provided on the new headrests.
The adjustment is made possible by using a wedge in the seat
tube similar to bike handle bar stem. So the side arms can be
moved up or down, and swivelled fore or aft to adjust the position
of the foam roll. "O" rings are used to seal against the
water into the seat tubes. Two "O" ring grooves are
provided. The upper one is for the standard 0.035" wall seat
tubes, and the lower, deeper, one for the heavy duty 0.049"
seat tubes, which are a little smaller on the inside diameter. A
small amount of grease will help the "O" rings to slide
in the top of the seat tubes. The foam roll is designed to fit the
nape of your neck, so that it does not interfere with the wearing
of a helmet. Price of the headrest in Oz is $120 AUD. Please contact
your local GS dealer or email Rachael to order.
Headrest Side Arm
2. New Tandem Stoker Handle Bars
It is a fact, that in general, women have longer legs and shorter
arms for their height than men. Thus a number of women have found
that the stoker bars on our Tandem Trike too far away to reach
comfortably, when the bars were on the end of the seat tubes. Thus
we have now redesigned the stoker bars so that they are attached
underneath the seat, to a new fitting on the main tube of the
frame. The "bar ends" are the same ones as used on the
new GTO handle bars, and are adjustable for both width and rake,
which also provides a measure of fore and aft adjustment. They
were introduced last month, after months of research, and are being fitted to all new
See pictures for details – note width marking on the bar ends
3. GS Options – The Rohloff.
I get a lot of questions from new customers about options, so I shall give you some of the history behind them,
and attempt to explain the advantages of choosing various GS options.
Barbara and Burnie Rohloff liked to ride their
bikes along the beach, but found that the sand clogged the
derailleurs and stopped them from working. So they had a dream about
making a transmission which could be ridden along the beach without
any problems. By putting all the gears and the shifting mech. inside the rear hub, this dream was achieved in the shape of the 14
speed Rohloff Speedhub.
IMO this hub is a huge leap forward, over all the
bike gear systems on the market. Why?
1. Lower maintenance.
derailleur gears which work by derailing the chain from one cog to
another, and are exposed to dirt, water, and accidental damage, the Rohloff internal
gears run in a sealed oil bath, much like a car gearbox, plus the
indexing system is inside the hub, rather than in the shifter. Thus
there is no need for regular gear adjustment, and derailleur
replacement. The oil needs changing only once a year, or every 5,000
2. Easier gear changing.
With a 27 speed
mountain bike you have TWO levers or twist grips. One for the triple
crankset, and one for the 9 speed rear cluster, and many ratios
overlap others, plus some combinations are not advisable, due to
chain misalignment. Furthermore there are uneven jumps between the
gears, so it is not easy to always select the right
gear. Whereas with the Rohloff, you have one shifter
which goes all the way from 1 to 14, covering the same range, with
even, slightly smaller jumps, making it much easier to select the
right gear. PLUS you can change ALL the gears when stationary,
as well as in motion. Thus if you've forgotten, or not had time to
change down after a sudden stop, you can easily select the right
gear before taking off.
In a single hub, you have the same range
as achieved by a 27 speed mountain bike set up with a 9 speed
cluster and a triple chain ring. Or a SRAM 3x 9 DualDrive hub.
However with the Rohloff you can change your whole gear range up or
down, by just changing one rear cog, rather than a whole cassette,
which is more limited in the sizes available. The Rohloff cogs are
available in 13,
15, 16 and 17 teeth. The internal ratios are :- 0.279, 0.316, 0.360,
0.409, 0.464, 0.528, 0.600, 0.682, 0.774, 0.881, 1.000, 1.135,
The Rohloff hub breaks
the mould for geared hubs. While other geared hubs use only plain
bearings in the pinions, and are greased once at the factory for
life, the pinions of the Rohloff run on roller bearings, and in an
oil bath, giving efficiencies comparable with derailleur systems.
Plus better chain alignment further increases efficiency
while reducing chain wear.
With a seat back behind
you, it is possible to put more force on the pedals of a recumbent
than an ordinary bike, plus with a recumbent trike you can gear
lower than a bike, as there is no falling off when the speed is too
low. Thus some people have managed to break some of the other geared
hubs, and we have broken the Shimano LX hub in testing. Whereas none
of our customers have even managed to break the safety shear pins in
the Rohloff. In fact I witnessed the hub being tested and approved
for TANDEM use at the Rohloff factory. Plus the bearings in the hub
are larger than used in other hubs. So whereas some customers have
worn out the bearings on the SRAM hubs by overloading their tandem
trikes on long tours, I would not expect this problem with the
Main disadvantage is the
cost, with the Rohloff option being a $1,350 AUD ($945 US) upgrade.
As the twist shifter is designed for ordinary
bikes, it does not work quite as well as the Shimano bar end
shifter, but this can be alleviated by dropping the hand down on the
handle so that the thumb and fore finger engage the twist grip.
Experiments with full length prototype twist grip shifters have not
shown a lot of improvement, as has inverting the twist grip. The
Rohloff factory is currently working on an electric shift and an
automatic version. The only other disadvantage we have found is that
they are generally noisier than the derailleur gears, esp. in the
lower 7 gears, when two gear trains are in operation in the hub.
In fact we have been so impressed by the Rohloff
that we have had special Rohloff dropouts made for our trikes, so
that should people wish to retro fit these hubs to our trikes, this
can be done without needing the large after market torque arm. The
LH dropout has extended fingers to engage torque stop on the Rohloff
OEM axle plate. Plus we are fitting both the cables stops needed for
the SRAM DualDrive, and those needed for the Rohloff. In addition we
have changed over to fitting the External Cable Box, originally made for
the disc brake version. While this is more expensive than the basic hub
with the bayonet cable fittings, it avoids the special fine,
small cable inside the hub, makes it easier to the remove the rear wheel,
and gives easier cable adjustment.
2353 x 3122
the Rohloff Speedhub
Shifter on Trike Handle Bar
External Cable Box
4. GS Options - The Schlumpf.
Schlumpf designed his Mountain-Drive, so that people with an
ordinary 3 speed bike would be able to climb the mountains in his
native Switzerland. Thus with this 2 speed bottom bracket, the two
gears are wide enough to give six speeds with a 3 speed hub, WITHOUT
any overlap. Thus while top gear is direct, low gear is only 1 :
0.4. That is for every revolution of the chainring, the cranks
revolve two and a half times! Thus if one has say a 60 tooth chain
ring, going down to low is like using a 24 tooth ring. This is a
much wider range than you would get with say a touring triple
crankset, where the rings are normally 52/42/30. The gear change is executed
by kicking a button in the centre of the cranks, dispensing with
cables and shifters. This can be done with the heel without taking
the foot from the pedal, or without disengaging clipless pedals. Hit
the right button for low gear, and left button for top gear. For
people with short feet, we have Easy Shift levers attach to the
crank arms, and extend over the buttons.
There are two other versions of the Schlumpf,
known as the Speed-Drive, and the High Speed Drive. The Speed- Drive
has a bottom gear of 1 : 1, and a top gear of 1 : 1.65. So this is
useful for cycles with small wheels, giving an overdrive of 65%, and
avoiding oversize chainrings. The High Speed Drive has a 1 : 1
bottom gear, and higher 1 : 2.5 top gear, and is useful for small
wheeled cycles needing a wider gear range.
Which Schlumpf to use?
choose the mountain-drive to extend their gear range beyond the
standard range offered by the standard DualDrive and triple set up,
which normally gives a gear range from 13 to 125 inches. The
standard 60 t ring will expand the range from
11 inches to 145 inches, giving gears high enough for a full
fairing, plus even lower hill climbing gears. For those needing
lower gears for mountain climbing with a camping load, or pulling a
heavy trailer, a 52 t ring is used giving a range from only 9 inches
to 125. The mountain-drive is available with both 130 and 110 mm pcd
spiders to take a wide range of chainrings. I have found the
mountain-drive particularly useful for fully faired trikes, where
use of an 80 t chainring will extend the range with the DualDrive
hub from 14 to 196 inches.
Some prefer to combine a Schulmpf with the Rohloff,
to eliminate all the derailleurs, and to have a cleaner looking trike
without the front derailleur post. The Speed-Drive is normally
used for this, as it needs a smaller chainring, has enough range for
most uses, and is more efficient than the m-d in low gear. The speed
drive will only accept chainrings with a 110 mm pcd.
The mountain-drive can also be used with the
Rohloff, as although this is not recommended for ordinary bikes, the
lower wheel loading on the trikes, plus the smaller wheel size,
reduce the maximum torque loading on the rear hub. This combination
has also been used successfully on our tandem trikes, where cranks
are connected 90 degrees out of phase, to provide a smooth power
The High Speed Drive is a new device, which has
the advantage of having roller bearings in the pinions, and should
be more efficient, but is only currently available with a 27 speed
chainring. This may give chain/cross member interference on some GS
trike models. The 27 t ring would be equivalent to a 67 t ring in top gear. Used
with the new Shimano Capreo 9/26 9 sp. cassette, and rear hub, this
would give a range from 17 to 124 inches with a 16" rear wheel.
The only disadvantage we have found with the
Schlumpf is that there is a small power loss in low with the m-d,
and in top with the s-d. However I don't notice it on the road, and
it seems a small price to pay the great range. Thus I've fitted one
to the new faired trike I'm building for myself, with a Rohloff rear
hub. More details in the next newsletter.
5. Christmas deliveries.
year, thanks to our expansion, we have managed to get a little ahead
with our orders for the 1st time, and can now guarantee
one month delivery on standard size GTOs in all frame colours.
Seasons greetings to all our customers and readers!
69 Mountain Gate Drive
Phone +61 (0) 3 9758 5541
Web Site www.greenspeed.com.au